Making use of ‘extra’ electricity off the grid

When someone has grid connected solar panels, they are usually trying to maximize total output, as they can sell all power straight to their power utility through the wires connected to their home. With off-grid systems, there is by definition no connection to the grid, so when you generate your own electricity, you are in a ‘use it or lose it’ kind of situation. As we’ve written elsewhere, solar electricity generation in an off-grid home isn’t about producing the maximum possible amount of power, it is about trying to make sure that you don’t run out. Further, there is great variation in the amount of sunlight available over the course of a year. Here in Ottawa there is four to five times as much energy available from sunlight during the long days of June than in December. On top of that, the cold and dark parts of winter require a lot more electricity to power things like lights and heating systems. Off-grid solar systems need to be designed to cover these winter needs, and so overproduce during all of the warmer and sunnier parts of the year. Putting all of this together, it means that most off-grid homes waste a lot of the electricity that the panels produce.

Up until December of 2018 this was the exact situation for the Manitou Bay house, where we were only using about 20% of the total power that the panels could have made available. During much of the year, our battery bank was full or nearly so, and all of that extra electricity was left unused. Knowing about this waste nagged at us, that we had all of this electricity with no place for it to go. We knew it was possible to do better and so made a plan to fix things, but due to it being somewhat lower priority as well as some unforeseen delays, it ended up taking almost three years to put that plan into action.

We have now installed some new hardware that allows us to utilize much of that wasted power. In principle, all we have done is add an automatic system that switches on some electrical devices anytime there is extra electricity available – on bright and sunny days. These extra electrical loads are called ‘opportunity’ or ‘dump’ loads, and need to be those things that are useful to us even though they only turn on during sunny days. This means that it can’t be things that we absolutely require, or those that we want available at a moment’s notice. We currently have one major need that fits this description, which is supplemental heating. Up until now much of our active heating has been accomplished with propane. The new system will do space heating through all the colder months, and make hot water for showers and the like during all of the summer months. We expect that this could cut our propane use at the house by a third (see below). In the next couple of years we will have one more use of intermittent power, to recharge an electric car, when we replace one of our current gasoline powered ones around 2021 or so.

This principle, of using electricity when it is cheaper or more easily available, is one of the main ideas that will underlie the ‘smart grids’ of the future. Right now most users simply turn on any power needs that they want whenever they want them, but in the future we will be able to set our heating, cooling, charging, and other devices to automatically turn on when power is cheaply available, and turn off when it gets more expensive. This will save everyone money, and will allow more renewable energy into the grid and give greater flexibility to utilities. What we have done with our upgrade is to make our off-grid home something of a ‘smart’ microgrid.

How the relay works (the rest of this post will be a bit more technical). In our situation, we are using the voltage of our battery bank to regulate our intermittent loads. When the batteries are full and the voltage is high the switch turns on, and when the battery voltage falls to about 80% the switch turns off, as we need to keep a healthy amount of power in reserve for all of the normal electricity needs. Our charge controller (system details here) has the components and software built in that can control a switch based on voltage. However, this switch can only control a low power direct current (DC) circuit, not the higher energy alternating current (AC) electricity that is typically used around a home. So this is why we had to add new hardware in December, installing a relay so that the DC circuit could control AC circuits that go out to the heating and plug loads where we have the intermittent power consumers.

How much electricity will we effectively gain by adding the relay? Before adding this relay, the house consumed a bit less than 5 kWh per day of electricity year-round, or about 1500 kWh per year. Based on a power production estimate that we had done when our solar system was installed, which is now doubled since we doubled the number of panels, our solar system could produce up to about 7500 kWh of electricity per year. Now that we have the relay, we will be able to capture much of that excess. From November to April we will put every extra kWh into space heating with a 1500 watt plug-in heater. In December this is only anticipated to be about 2 kWh per day, while in April there should be an extra 20 kWh per day. From May to October, the extra electricity will be routed to a standard electric hot water heater. We estimate that with the number of showers that we take that we will consume around 10 kWh per day of electricity through the water heater, which still will leave a fair amount wasted during the sunniest months of May to August. Add all this extra power up, and we will use around 3600 kWh of additional electricity. We should now be using about 70% of the total output of our system instead of the 20% that we managed before the relay was installed. See the table below for specifics.

MonthDaily extra kWh usedEnd use
January4space heating
February9space heating
March18space heating
April21space heating
May10hot water
June10hot water
July10hot water
August10hot water
September10hot water
October10hot water
November4space heating
December2space heating
Annual total3600all uses

We’ll wrap up by going over the greenhouse gas emission and financial reasoning behind this project. Before adding this relay the home was using about 400 gallons per year of propane. Adding 3600 kWh of electric heat should reduce the propane consumption by around 140 gallons. By avoiding burning all of that propane, we will reduce our CO2 emissions by a full metric ton each year (this is a part of our 5 year plan to reduce our emissions by half). The cost savings for that propane not purchased will be around $350 per year as long as the system keeps running. The relay work cost a bit less than $1000 and the electric hot water tank cost about $500, and so the work will pay for itself in under 5 years. Finally, I ought to mention that even with this increased efficiency, solar electricity off the grid isn’t cheap. Considering all the panels, electronics, batteries and labor, and the fact that most of these components only last for 10 to 20 years, even with the relay our solar electricity still costs around $.50 per kWh. This compares to power from the local utility, HydroQuebec, that comes in at around $.10 per kWh. With the secluded location of the home off-grid was the only sensible choice, but the costs do make one appreciate the value one gets by tying right into the power grid.

Special thanks to Tom Hewitt at NetZero Construction for his assistance with the solar and DC circuit work, and Jean-François at Lamarche Electric for all of his work installing the relay and AC circuits.

Visualizing carbon dioxide pollution

I think that a big problem in getting people to care about carbon dioxide pollution is how abstract it is. It is a transparent, odorless, non-toxic gas that is already naturally occurring in the environment. We don’t see it, feel it, touch it,  or experience it in any substantive way in our daily lives (see ‘Salience’ on this page) even though it is causing a global calamity. So I thought that I would go through a quick thought experiment that allows one to really visualize how much of this stuff we are producing.

In 2011, each American’s share of carbon dioxide pollution (and equivalents like methane) added up to about 24 metric tons. This isn’t an amount that is easy to think about. Our daily lives revolve around things that weigh pounds or kilograms, and we don’t often think about weight at all when it comes to gases. So though this is a good accounting method for scientists to measure carbon pollution, it isn’t useful for visualizing it. So we’ll describe it in two other ways to be able to better picture what we are doing.

As a gas at normal temperature and pressure (like the air around us), how much space would 24 tons of CO2 fill up? A quick conversion from weight to volume (calculator here) shows that the CO2 per American per year is about 450,000 cubic feet (13,000 cubic meters). This still isn’t a number that we can visualize, so lets imagine that we replaced all the air inside of a building with the CO2 that one person produces in a year. It could completely fill the living space of a 40,000 square foot building with 10′ ceilings, like the mansion below.

Or it could completely fill up a 20,000 foot warehouse with 20′ tall ceilings, like this one:

To reiterate, this is how much CO2 is produced per person each and every year. It is an absolutely enormous amount.

Or lets look at it another way. If one took that 24 tons of CO2 gas and cooled it enough, it would freeze and give you dry ice. Dry ice looks a lot like regular water ice, but it is a bit more dense. If you made one ton cubes of CO2 ice, each cube would be a bit less than 3′ (1 meter) on each side. 24 tons of dry ice would fill 530 cubic feet (15 cubic meters), enough to fill a large moving van.

When one thinks about it this way, it really starts to put things in perspective.  Because our current economies are so dependent on fossil fuels, and these fuels give off CO2 when they are burned for energy, almost every activity we do produces carbon dioxide. We need to keep this in mind, and not just think about the physical things that we touch that were produced with oil, like plastic products. Each mile traveled, each service used, they all produce carbon dioxide. We are starting to decarbonize our economies, meaning that the carbon pollution for each activity is decreasing. But we need to keep the primary goal front and center, to get the net level of CO2 that humanity produces down close to zero.

The inspiration for our farm and Sunshine Saved

I always wanted to own property in the countryside. I loved the hiking, fishing, canoeing, and other related outdoor pursuits. But there is something different when one is the owner, the land manager, and if done right, the steward. When we relocated to Ottawa, the Canadian capital, finding a place outside the city to call our own was something that was at the top of the list. Within a year of our arrival, we found our perfect spot – nearly one hundred and fifty acres of field, forest, and wetland, spread across rolling hills and nestled alongside the Gatineau River. It felt quite wild to me at the time, but they called it a farm. It was little like the flat open farmland that I was used to seeing during my childhood in Minnesota and Wisconsin, where fields run together and sometimes the only trees are those just adjacent to farmsteads and along fencelines. On this property, there was no barn or silo, but rather a few modest hilly hayfields, and a forest where trees were cut occasionally for lumber or firewood. When my wife and I had begun looking for our countryside escape, we thought about what we wanted mostly in terms of lifestyle and recreation. But it is a farm, and we had become farmers.

From the time we purchased the property, my mind was overflowing with the possibilities of what we could do there. Of course, much of my attention was on all of the recreation that our family would be doing, a broad swath of sports, including snowshoeing and cross country skiing all winter, hiking and fishing the rest of the year, a bit of deer and grouse hunting thrown in during the fall. But it was never just about recreation, it was also about stewardship and sustainability, taking proper care of a space, using it in the present, but preserving it for the future. As much as possible, we wanted to live lightly on our new property, preserving the full range of flora and fauna that are found there. The main reason for choosing this particular property was the natural aesthetic of the place, which we wished to preserve. Since I was a young child, I had dreamed of living out in the wilderness, of living off the land. But as I grew to adulthood, I realized that the sort of rugged independence where I would build a house by hand and grow all my own food was not the dream that I was pursuing. I have no desire to be fully separated from the rest of the world; people are social beings, and productive societies always exist by working together, each specializing to use his or her own talents and predilections. We need those goods and services that others produce, but I also knew that we needed to make sure that we, as a world, live in a way that is sustainable so that our children and their children will be able to continue to prosper as we do today.

Real sustainability isn’t only conservation, and leaving all natural places free of human influence. While true nature refuges are critically important, people also need to produce many goods from the land to support themselves. I felt that part of my responsibility was to continue to keep this land productive, to help provide for human needs as well as to be a wild and natural place. A question kept coming back to me: Was our farm, in this rocky and hilly Canadian forest, even capable of being productive enough to support my family and our needs? As I began to work through all of the possibilities, I considered how it was possible to compare them; Should we grow trees or corn? One way to answer these questions was to simply ask which one would yield the highest dollar returns. This is certainly the typical way that farmers make their land-use decisions. While we wished to make a few bucks, concerns of sustainability stayed at the fore, and our main incomes will always be off the farm. I then had an epiphany about our land use planning. It wasn’t the most original, but it is one that is key to land management, and I’ll share it with you: All farming and most sustainable land use is the farming of sunlight, capturing some of those rays and using the energy contained in them. One takes sunlight, and converts it into maple trees or wheat, chickens or deer. So my realization meant that the question that I was asking about providing for my family was really a question about energy. I started to come around to thinking about sustainable land use more broadly as being about energy; how much energy could we capture and use? What kinds of byproducts and waste would be created? Was a farm like ours capable of producing enough to support the energy-intensive modern lifestyle of my family? How much energy does it really take to support a family anyway?

At the same time as we were purchasing our property, we were also busy with starting to design a house that we would build on a hilltop overlooking the river. For years I had also been interested in architecture, particularly green building practices and energy efficiency, and so we decided to design a place that would be incredibly energy efficient from the ground up. We received an extra push for efficiency from the fact that our building site was so far from the nearest power lines that it would have cost a small fortune to run power to our new home. Solar photovoltaics were going to be the only reasonable way to provide electricity. Going with off-grid solar almost automatically puts one in an energy conservation mind-set, because for every extra light or computer you want to power, you need to pony up more cash upfront to install more panels and batteries. Energy of all kinds was going to be at a premium at this location, so we made decisions to reduce use and keep all appliances and mechanical systems efficient. To reduce heating needs, we took inspiration from several different green design movements to incorporate passive solar design and superinsulation to our home. All in all, we reduced by approximately 70% the amount of energy that we will need to use in this home compared to standard construction. In working with an architect and tradesmen of all kinds, I learned the ins and outs of energy flows around and through a home, and in many ways they really didn’t seem so different from the energy flows involved with land use.

While working on both land use planning and home design, I was consulting innumerable sources, on forestry, farming, energy, architecture, and more. As written, each of these sources was aimed primarily at specialists, the professionals who work in these fields. What wasn’t there, and that I yearned for, were some of the threads that tied all of these concepts and practices together. How did each of these fields relate to the human level, an individual, a family? Again, I could see that in each, a common theme of energy use was central to each of these endeavors. Sustainability and renewable energy are tightly intertwined, and I was learning enormous amounts about how these systems worked, and could see a place for sharing this knowledge with others. Much of this website is built on this inspiration and these insights, putting together the ideas and resources that I was searching for on our own path to a more sustainable lifestyle.

Our 5 year sustainability improvement plan

Shifting to a truly sustainable society is going to be a long process and will require many adjustments both large and small to the way that people live. We here at Sunshine Saved want to do what we can to fast-track this change, and as part of that we have made plans to reduce the carbon emissions of our family’s lifestyle by half within the next five years. Hopefully this will provide some inspiration for others to find their own ways to reduce their footprints. This article builds on the accounting that we did for my family’s 2017 resource consumption, figuring out what we can and will do in the near term to increase the sustainability of my family’s lifestyle, projecting out to 2022. We’ve taken some important steps already but have much more to do.

Everyone is in different circumstances of jobs, income, locale, lifestyle, and family, and that will be reflected in which things they could do to improve sustainability. For us, and for a majority of North Americans, one of the highest priorities is to reduce usage of fossil fuels. And in fact this is the main work that we will do with our 5 year plan, to directly reduce our usage of gasoline, natural gas, and propane.

Overview of our current emissions

The above chart shows our 2017 carbon emissions on the left, and the target for our 2022 emissions on the right. Carbon emissions aren’t the only way that we look at our impacts, but they are very important and easier to measure and quantify than many other things. As you can see for our 2017, the biggest contributors were related to housing, our personal vehicle use, food, and consumer goods. We are targeting each of these in turn as you will see in our action plan below. In 2017 we had emissions of 28 tons of CO2e for a family of four, and the plan for 2022 is to be down to 16 tons of CO2e for our slightly expanded family of five. This would bring us down from 6.9 tons to 3.2 tons per person, more than a 50% reduction.

As you will see below, we are putting our efforts into those things with the most ‘bang for the buck’ both in terms of dollars but also effort. Making changes isn’t easy, so we are trying to really focus on changes that provide big impact with as little effort as possible, as well as those things that we will enjoy or otherwise be able to maintain. For instance, switching to an electric car (or simply a more fuel efficient gasoline powered car) is a single decision that will reap benefits for the lifetime of the vehicle without any further effort. But for something like cutting out plastic packaging, this requires continuous and daily changes in behavior such as only shopping at specialty and bulk stores, losing a lot of convenience and taking more time and constant effort. This isn’t to say that reducing plastic use isn’t a good idea, it is just that other things should probably be prioritized over it.

Finally there is the direct monetary cost. Very few people are going to freely choose a more sustainable pathway that is twice the cost of ‘business as usual’, but there are many ways to go green while also protecting the pocket book. Reducing consumption usually directly reduces costs. Some of the bigger steps may take more cash and planning up front, but they are followed by big savings in the costs of fuel, maintenance and replacement later on. So while we won’t go through all of the finances of our decisions directly in this article, the combination of all of the moves outlined below shouldn’t cost us any more than a business as usual scenario .

Housing in the city of Ottawa

In 2017 we lived in a rented semidetached home (duplex) as outlined in a prior article. We knew that we wished at some point to purchase a home in the city, and sustainability concerns certainly figured prominently in our decision making process. We were able to find the right place and moved into it in mid-2018. This home is another semidetached dwelling, and our half of the building contains a main unit on the upper levels along with an apartment to rent out on the basement level. We are intending to stay in this home until our children are adults, and with a newborn in the summer of 2018 that means we have a good 20 year planning window. This longer timescale makes some sustainability changes more viable; for instance, if we put in higher efficiency appliances or more insulation it is us who will directly reap the long term energy savings.

Reduction in driving – As they say, “location, location, location”. As so many do, one of the main criteria for our new home is how well located it is from the places that we regularly go. In our case, this is school for the kids, work, errands to stores, and the farm. We were able to narrow down to a couple of neighborhoods that would reduce the distance to all of these places, and our new home is now in walking distance from the kids’ schools and a new light rail station that one of us takes to the office. It is also 10 minutes closer to the farm. Altogether, this new location should reduce our driving (already lower than average) by one third or more.

Heating – Our new home came with a natural gas forced air furnace. Around Ottawa this is the default choice for the majority of residential homes, and the same as our prior rental. This is the cheapest option in a typical home in our area and produces a medium level of carbon emissions as compared to other options. This is a new and high efficiency furnace, and we decided that augmenting the existing furnace with auxiliary forms of heating would be the best way to reduce the amount of fossil fuels that we use.

The biggest heating problem in this house on moving in was for the basement apartment. The basement is insufficiently insulated, and so is always significantly colder than the main unit (We would like to re-insulate the space, but this won’t make it into the five year plan,  but should for the 20 year plan). Further, the house’s gas furnace isn’t ‘zoned’, in that it either provides heat to the whole building or none of it. Put together, this means that the basement needs an additional heat source. We considered electric baseboards, but instead have settled on a much more efficient option, a Mitsubishi cold climate air to air heat pump, also known as a mini-split (we’ve discussed heat pumps before here), installed in September of 2018. This heat pump, though a bit more expensive up-front, will use only  a quarter as much electricity as electric radiant baseboards, and will have a very low carbon footprint due to the clean energy grid that Ontario has in place. This heat pump will give the apartment renter full control over the heat in the apartment. It will also provide for some of the baseload heat for the upstairs as much of this heat will rise up from the basement to the upper levels. Only time will tell for the exact numbers, but quick calculations suggest that the heat pump may reduce natural gas usage from the furnace by about a third.

The second way that we will reduce our natural gas use is to do a significant amount of our home heating with wood. This isn’t a solution for everyone, but with working from a home office, enjoying tending a fire, and having a nearly unlimited supply of sustainably cut local firewood, it makes a lot of sense for us. The house currently has a 35 year old fireplace on the main level. Most older fireplaces actually provide little relief on heating bills; they heat up the room that they are in but they also suck vast amounts of warm air from the inside of a home and send them up the chimney. They also burn inefficiently and produce a lot of unhealthy air pollution. However, newer high efficiency wood stoves are another story completely. They tightly control the fire and airflow, allowing them to burn very cleanly as well as do an excellent job of heating a home. In 2019 or 2020, we will swap out the current fireplace for a high efficiency woodstove. If things go as planned, a fire will burn on half the days through the winter, which should further reduce the remaining heating needs of the house by half.

To summarize:

  • The new home is a bit bigger than our 2017 rental, and so we estimate that it will use 50% more natural gas than our 2017 numbers if we make no changes to our behavior. Heat is now provided for 6 people.
  • The combination of a basement heat pump and a regularly used wood stove will reduce natural gas consumption by 2/3
  • Combined, this means that we will use half as much natural gas as we did in 2017,  using 740 cubic meters of natural gas which will release 2 tons of carbon dioxide in 2022
  • This means .35 tons of CO2 per person per year, down from 1 ton per person in 2017, a 65% reduction in natural gas consumption

Our house on the Farm at Manitou Bay 

The home at the farm is off the grid, with electricity produced by solar panels and heating done mostly with propane. With solar panels that are connected to the grid it is easy to sell any extra electricity on to other users, but this isn’t possible off-grid; either you use the power or it goes to waste. So in the first few years this home had no way of using any extra power and it was wasted, but we have figured out a way to change that. We are going to add a smart switch that will turn the power on in some circuits when the batteries are full and then turn off the power when the batteries drain down to about half full. The cost to implement these changes should be paid off in 2 to 4 years in reduced propane costs.

This extra electricity can then be used in ways that allow us to reduce other energy use, in particular the propane heating. In the winter any extra electricity can be directed into a resistance heater which reduces the amount of heating that we have to do with propane. From spring through fall, some of the electricity can be used in an electric hot water heater, bypassing the need to use the current propane water heater. Finally, once we have a plug-in electric vehicle (see below), we can use any additional ‘extra’ electricity to charge that vehicle.

We hope that by using all of this currently wasted electricity that we can cut our propane usage in half. This would bring us down to 200 gallons per year, and reduce CO2 emissions from 3 tons to 1.5 tons per year.

Replacing our vehicles with electric ones

We would be happy going down to one car, but that may not happen in the 5 year plan. This depends in part on what happens with car services (car sharing, Uber, Lyft, the coming of autonomous cars, etc.). Between managing a family with three small children and also regularly traveling to and working out at the farm, we wouldn’t want to give up our vehicles until other options could replace the conveniences of having our own.

What we can do instead is to plan to only buy electric cars from here on out. We will make that switch as soon as electric vehicles come available that can meet four key needs: a range of about 200 miles, big enough for our family’s needs, all wheel drive, and relatively reasonably priced. These cars are certainly on the near-term horizon. There are already several electric vehicles available that meet three of these four criteria, but not all of them. Dozens of new models of electric vehicles from most of the major manufacturers are due to be released by 2021. We eagerly await those vehicles that could serve our needs.

Electric cars are already better for the climate in most jurisdictions, but they are a particularly good choice in Ontario and Quebec. This is because the electrical grid in these provinces produces very little carbon pollution, being mostly powered by hydroelectric and nuclear power plants. This means that almost all of the carbon pollution from owning these cars comes from their manufacturing rather than driving them. An electric car does have a higher manufacturing footprint as a comparable gas car mostly because of the resource intense batteries, but cutting out the gasoline itself still leads to enormous overall reductions in pollution. As the vehicles that we will purchase next aren’t even available yet it is hard to calculate any precise estimates, but my best guess is about a 75% reduction in our vehicles’ total carbon footprint, a very large savings.

Growing our own food

We have a lot of plans for our in terms of forest management and some farming endeavors which are discussed over at our farm page, but much of that work isn’t relevant to anyone who doesn’t manage a larger property. The part that is more applicable to this discussion is food, namely that we are going to grow much more of our own food. Our ambitious goal is to get to half of our family’s food produced directly on the farm. As of the writing of this piece in the fall of 2018, this work is still in its infancy. The orchard was planted just this spring, and the preparatory work for a much larger garden is currently underway. Livestock should become part of the mix by 2022, but may be limited to broiler chickens which we would acquire as chicks in the spring and harvest in the fall.

For all of our farming efforts we are going to be applying the principles of regenerative agriculture, trying to maintain the health of the land and soil as we grow our food. We will use little or no pesticides and intend to use natural fertilization rather than chemical fertilizers. We will further avoid leaving bare soil, which will help to hold soil carbon and reduce erosion. Needless to say, this will reduce the ecological footprint, including the CO2 emissions, associated with our food. If we are able to scale our production to the level of half our family’s food production, it should also reduce the emissions associated with our food by a similar amount.

If you’ve made it all the way through this piece, then you may be interested in seeing numbers used to make our 2022 estimates. They can be found in the table above and are being shown next to our 2017 numbers. It won’t quite be a 50% reduction in absolute terms, but will be over 50% when one considers the per person emissions. Now we just need to carry through with the rest of the plan.

How much energy does my family use anyway?

***If you are not a numbers person I apologize in advance, and suggest that you don’t worry too much about the precise details and instead just try to take away the bigger picture.***

If a person wants to live more sustainably, one very important step is to take stock of your current circumstances. Putting real numbers to one’s use of energy and resources allows you to see which things really matter, where the problems are, and gives hints to the solutions. This post is an accounting of the energy consumption and associated emissions of greenhouse gases of the lifestyle lived by my family during the entire year of 2017. We have already taken a fair number of steps to minimize the impact of our lifestyle, but we still have much work left to do if we are to do our fair share to keep the world livable.

Something like 80% of the energy and resources that we each consume is connected to household goods and services, with the rest being our share of the services provided by the government. The majority of this resource use is under our direct control in our homes, our cars, our products, and our food, while the rest is only indirect; we don’t control that much about the hospitals, businesses, or restaurants that we frequent. For the purposes of figuring out what the average person can do about sustainability, it makes sense to separate out those things that are under our direct control from those that are not. It isn’t that we can’t have an impact on government or industry, it is simply that the advocacy related to voting, lobbying, or boycotting organizations to change their policies and behavior is very different from the decisions we make about heating our homes and which cars to buy.

For the purposes of accounting for my own household’s energy use, I’ll stick to those things that are under our direct control, namely housing, consumer goods, personal transportation, and food, and not address those that we don’t have a lot of control over, government and services including things like hospitals and schools.

We begin this account with a table including our major sources of energy consumption in 2017, seen below. This includes my best approximation of everything that we did and its impacts. This table breaks down where and how we used energy as well as what form it took. I then include the figure that matters most for climate change, emissions of tons of carbon dioxide equivalent (CO2e). Most of these emissions are actually carbon dioxide, but also include things like nitrous oxide and methane. We’ll examine each of these energy uses in turn below (these estimates are drawn from various sources, anchored by analyses from Jones and Kammen, 2011). As you can see in the table below, our direct household activities had effective emissions of 28 tons of CO2 in 2017.

Duplex in Ottawa

I would actually much prefer to live full-time out at our farm in the hills north of Ottawa, but this would require a daily commute of an hour each way into the city for work, and schools other services are very limited out in that area. On top of that, my wife isn’t ready to be a full-time country woman. So instead, we have been renting a 3 bedroom duplex unit in the city, and then spending two or three days a week out at the farm.

Our biggest energy consumption in the duplex is natural gas, used in a forced air gas furnace and a tankless hot water heater. Natural gas is, unsurprisingly,  delivered in gaseous form, so it is measured by volume; we used 1480 cubic meters of the stuff in 2017 (52,300 cubic feet if you’re in the US). Natural gas heating is currently cheaper than almost any other source of heat in much of North America including here in Ottawa. From a sustainability standpoint, it is an imperfect choice because it is a fossil fuel, but it isn’t quite as bad as other fossil fuels for emissions. Society must wean itself off of natural gas in the future, but it is a tolerable choice for the time being. At the moment, the best local choice for more sustainable residential heating may be heat pumps backed up by natural gas on the coldest days, which may be the path we take once we own a home in Ottawa.

The lion’s share of this gas is for space heating in Ottawa’s relatively cold climate. Ottawa has similar heating needs to some of the coldest areas  of the continental US, very similar to Minneapolis or the colder parts of New England. The building itself is nearly 100 years old, but has been renovated and has relatively new insulation and windows. It probably has insulation and air-tightness levels of a typical 10 to 20 year old home. One big advantage is that as a duplex it shares one entire wall with an adjacent unit, which reduces heat loss for the whole building by around 25%. We keep the thermostat set a bit low in winter, around 19 Celsius ( 67 Fahrenheit), and have a smart thermostat that turns down the heat overnight. Combined, these measures probably shave another 5 to 10% off the heating loads as compared to business as usual.

We have a tankless hot water tank in this house. The benefit of tankless hot water is that one only heats up water when it is called for, and doesn’t have ‘standing losses’ when hot water in a big water tank cools between use. Having lower flow shower heads and keeping showers to a reasonable length also moderate hot water use.

We used 6635 kWh of electricity from Hydro Ottawa in 2017 in our duplex. Ontario (and neighboring Quebec) have very low CO2 emissions for their electricity since very little of their power is generated through fossil fuels. Across the river in Quebec power is almost exclusively generated by hydroelectric dams, and here on the Ontario side, in addition to significant hydropower, over half of Ontario’s electricity is generated at nuclear power plants. Nuclear power has concerns of its own, but if one takes climate change seriously it is something that should probably be included in the mix as nuclear power produces almost no greenhouse gas emissions. Our personal electricity use is fairly typical, with most of the power accounted for by the furnace fans, dehumidifier, dish and clothes washer, refrigerator, and household electronics. Our landlord did a good job of choosing high efficiency appliances.

The final energy use of our duplex is embodied energy. As discussed elsewhere on Sunshine Saved, the basic idea is that it takes a lot of energy and resources to build things and those things eventually wear out, so one can calculate how much energy is being ‘used up’ each year in deterioration and aging. There are an awful lot of parts making up a house, concrete, wood, electrical and plumbing, lots of of workers and goods transported to the site, and more. The saving grace is that houses last a long time, perhaps one hundred years on average. One can then add up all the energy that goes into building a home and divide that by the number of years it will last. Doing this, we estimate that the aging of our home accounts for the equivalent of 1 ton of CO2 emissions per year.

The house at The Farm at Manitou Bay

Our off-grid home is discussed in great detail here, and the design and building process for this house launched our work here at Sunshine Saved. This house was designed from the ground up to be efficient, both for reasons of sustainability as well as to make it much easier to take a four season home in our northern location off the grid.

Though this house has solar panels, the energetic heavy lifting is being done by propane. The biggest energy user of any home in our climate is heating, and this is the exact same time of year when days are the shortest and cloudiest.  It is, at least for the time being, enormously more cost effective to have the majority of heating come from sources other than our solar panels.

Propane is used for the primary heating, domestic hot water, kitchen stove, and a  backup electricity generator. In 2017, we burned 400 gallons of propane, which released 2.9 tons of CO2 in emissions. The biggest part of this was space heating. The Manitou house uses about half as much energy for heating as the duplex due to high insulation and airtightness, even though it is a slightly bigger place with much more surface area exposed to the elements.

Solar panels provide for all of the electricity loads. Sunlight as a ‘fuel’ has no emissions, but there is a quite high embodied energy for all of the solar equipment, the panels, electronics, and batteries. All of this gear requires energy to build and it has only a finite lifespan, 10 years for batteries, perhaps 15 for the electronics, and 30 for the panels themselves. I estimate that in 2017 we used 1200 kWh  and had an emissions impact of .3 tons CO2e.

In the winter, we heat with our wood stove whenever we are there to tend to it. There is an ongoing debate as to whether burning wood should count as carbon neutral, and my take is that it really depends on scale. Clearcutting forests and shipping them off to be burned for electricity is clearly not carbon neutral. However, the small-scale harvest of trees that would otherwise rot on the forest floor is quite sustainable. I estimate that we have effectively zero emissions as we are selectively cutting trees within a few hundred yards of the house, those trees that are dead, dying or of otherwise low quality. CO2 is absorbed as they grow,  CO2 is released when burned in our high efficiency stove. The only other inputs are less than a gallon of gasoline for my chainsaw to do the cutting for a winter’s worth of wood. The amount of wood we burn gives us about 1/4 of the home’s winter heat and produces only a few pounds of excess CO2 emissions from the gasoline.

This house is relatively similar in total size to the duplex that we rent in the city, and so we use the same estimate of its embodied energy, at 1 ton of CO2 per year. With the quality that we tried to aim for with the build, I would hope that this building will last much more than one hundred years, but only time will tell.

Car and truck

At the moment we have two vehicles, a Subaru Outback and a Ford F150. For a family trying to be as sustainable as possible, I admit that this seems a bit odd, to have two vehicles and one of them very large. We would like to reduce to one vehicle, but that has not yet become practical with the needs of a family of five, with work, errands, and a farm property to manage. All wheel drive is a necessity to access the farm during parts of the year, and is much better during the long snowy season in the city of Ottawa also. Managing a forested farm is also made much easier by the capabilities of a pickup. We keep the mileage and therefore gas consumption low, which does help some to reduce the impact of having two vehicles.

In 2017, we put about 6200 miles on the Subaru and burned 220 gallons of gasoline, and had 3400 miles on the pickup truck for an additional 200 gallons of gas. This released 4.9 tons of CO2 into the air.

Finally, there is the embodied energy in our vehicles, from all of the mining, refining, production, and assembly needed to put the cars together in the first place. One can tally up the total amount of energy, and divide it by the lifetime of the car, giving an annual emissions for having that vehicle. Our pickup is a bigger vehicle and so required more materials, and the two combined lead to an annualized production of around 1.4 tons of CO2.

Air travel

The energy use of air travel is something we discussed briefly in another article comparing modes of transportation, but the takeaway is that traveling by commercial airplane is roughly as energy efficient per mile as driving a car, while air travel really racks up fuel use and emissions due to the large distances traveled. In 2017, my family of four took one trip by plane to visit family, with about 1900 miles in the round-trip flight. Our share of the jet fuel for these flights released 2 tons of CO2.


My family tries to eat well and maintain a relatively balanced and nutritious diet. With very young kids it is seldom that we eat out, but we do a lot of home cooking. Most of our calories come from the grocery store, and from conventional farming before that. We do eat food out of the garden, from local farmers, and a bit more that is hunted and fished, but these make up a very small amount of the total. So for the most part, the sorts of figures discussed on our main page on food and diet apply to my own family as well. We have already adopted the two main recommendations that are outlined there, of cutting food waste almost to zero, and reducing beef and lamb consumption down to only a few times per year. Accounting for all of the farm and commercial equipment needed to plant, harvest, process and deliver our food to us, I estimate that our food consumption accounts for 4 tons of CO2 production per year.

Other consumer goods

On top of the big items of homes and cars, we have all the other trappings of modern life, including appliances, furniture, electronics, clothing, and more. And all of this stuff has a limited lifespan, whether it be measured in days or decades. This is a lot of things to try to account for, so for the sake of simplicity I will simply assume that we buy the same amount of stuff as the average American household (see here for more data). It would be interesting to go through item by item, and that is something that we may discuss at a later date. Using average American household figures, all of the goods that we purchase per year produce emissions of about 6 tons of CO2.

Comparison to average household.

Using the average household data, we can then compare where we were for 2017 with the average American household of 2010. The table shows that our household produced about 28 tons of CO2 compared with the average US household of 42 tons. We are doing better than the average family by about a third. The key differences that allowed my family to have lower than average emissions include:

  • Much lower mileage on our cars led to much lower gasoline use.
  • Our homes are well insulated and have efficient appliances and use less natural gas and electricity.
  • The grid electricity in Ontario has much lower emissions than most of the United States, so the impact of our electricity use is much lower.
  • We eat very little beef and waste little food.


My family’s 2017 consumption was far from sustainable. We are a bit better than the average North American level, but we have plans to do much more. We have put together a five year plan for our family where we aim to reduce by half our CO2 emissions from our 2017 levels. We’re even developing a more speculative 20 year plan that would bring our family’s consumption down to truly long-term sustainable levels. This longer term plan is less certain because it depends on larger forces of technology development, future government regulation, corporate action, and more. There are actions that we can take as individuals, but that alone will not be enough.

Hopefully this sort of detailed accounting will give some better context for the big numbers that are always being thrown around in discussions of climate change and climate policy. It all comes back to the decisions that each of us make every day – the things we buy, the places we go, how we choose to live. People need to understand how the pieces fit together and what is at stake so that they can act personally and to help change society at large.

Loss of biodiversity – the scope of the problem

A very quick version of the problem of biodiversity loss:

  • The earth’s ecosystems consist of the interconnected webs of species (plants, animals, fungi, micro-organisms) living together in different locations around the world.
  • Humanity relies on these ecosystems for our very survival – they produce the fresh water, clean air, food, wood and other natural products that are indispensable to our lives.
  • The earth’s ecosystems are currently being vastly disrupted by human activity causing species to go extinct, and the health of ecosystems to diminish
  • We need to change how humanity acts in the world so that we can preserve and repair ecosystems and stop extinctions, if not for the sake of other forms of life, then for ourselves.

And for a little bit longer version…

There are millions of species on the earth. The exact number is not known, but best estimates are that there are as many as ten million, with over one million having been identified by scientists. Ten million is a huge number, but a finite one. It has taken billions of years to produce these species, all of the animals, plants, fungi, and micro-organisms on the planet. Though there are many species, each is unique, and if they go extinct, they are gone forever.

Ecosystems are groups of species that all live together in a certain area. There can be many thousands of species, and they constantly interact and rely on each other to maintain the integrity of the whole. Plants form the basis of the food chain, taking energy from the sun and turning it into living tissue. Different plants fill different niches, some as tall trees, as grass, as climbing vines, some dropping their leaves for the winter and others keeping them all year. There are animals eating plants, other animals eating those animals, fungi decomposing everything that dies to recycle nutrients and begin the growth anew. Micro-organisms are found by the trillions in every nook and cranny.

While some (myself included) could wax poetic about the grandeur of wild spaces, of the beauty of old growth forests, or the thought of herds of bison roaming the prairies, providing beauty is far from the only thing that ecosystems do for us. Critical to the very survival of humanity are all of the things that ecosystems do for us, often called ecosystem services. Intact ecosystems provide us with soil, food, water, medicine, wood and other plant fiber, they maintain climate and rainfall patterns, and more. To provide all of these functions that we hold so dear, ecosystems need to be maintained in a healthy state. There are innumerable instances where people’s damaging of lands and waters led directly to massive problems in human society. Floods, soil erosion, desertification, wildfires, polluted water, can all be caused by poor management practices, and can threaten the very foundations of societies. In today’s world, climate change is linked tightly with ecosystem damage, as poor forest management and poor agricultural practices are some of the main drivers of a warming planet. Climate change in turn then causes more damage to those same ecosystems, as changes are now occurring more quickly than these systems can adapt. In terms of species extinctions, it is estimated that current human practices are causing the rate of species extinction to be a thousand times higher than what it was before the modern age, and we are currently be losing thousands of species every single year.

People need to act now to preserve ecosystems and species. We know that ecosystems are resilient, but it is unclear how much abuse they can take before problems may spiral out of control. There is something called the precautionary principle that tells us that we shouldn’t take dangerous actions when we are unsure of how risky they are. The cost of doing nothing could be absolutely immense, whereas if we act now to change ‘business as usual’, we know that this is likely to lead to great outcomes for both people and the planet. There will be some costs associated with making these changes, but the long-term benefits to saving ecosystems and species far outweigh the short-term benefits of such practices as massive scale clear-cut logging or agricultural practices that destroy the fertility of the soil.

Global climate change – the scope of the problem

The super short version of the problem of global climate change is as follows:

  • Carbon dioxide and other greenhouse gases in the atmosphere trap heat from the sun
  • People are vastly increasing the amount of greenhouse gases in the atmosphere, which means we trap more heat, which means the temperature of the planet is rising
  • A fast rising temperature causes massive problems for humanity and all other life on earth
  • We need to stop putting extra greenhouse gases into the atmosphere if we want a livable and sustainable world

I’ll unpack it a bit further in the following paragraphs, but will keep it to a few paragraphs as there are a great many resources that outline the ins and outs of climate change.

First, there is a natural carbon cycle on the planet. Carbon is a basic physical element, found in great quantities both on the surface and in the center of the earth, though it makes up only a small proportion of all of the matter of the earth. Most of this carbon is under the surface, bound up in rocks, in the earth’s core, or in fossilized plants that have been buried by the action of water, wind, geology and time. Then there is the carbon found on or near the surface that cycles back and forth between the air, the water, the rocks the soil, and living things. All life that we know is built out of carbon molecules, and all living things spend much of their time and energy bringing carbon into their bodies. Plants draw it from the air while animals eat other living things made out of carbon. The earth’s cycle of carbon is always in flux, plants are growing and dying, animal populations rise and fall, rocks and water absorb and release it. The main point to make about the cycle is that the amount of carbon actively moving around the surface, the waters, and the atmosphere, stays at roughly the same level and changes only on the scale of thousands of years. The equilibrium amount of carbon in the atmosphere, mostly as carbon dioxide, has stayed about 300 parts per million (a quite small proportion of the air) for at least hundreds of thousands of years up until about one hundred years ago.

The problem that we face today is that people have thrown off this balance, as human activities have drastically increased the amount of carbon going into the atmosphere, much more than the natural systems and cycles can absorb. The most notorious source has been the fossil fuels of coal, oil, and natural gas. These substances once were living organisms, and were trapped underground and transformed into concentrated carbon based energy. When we burn them, we release carbon back into the atmosphere that has been out of circulation for millions of years. Another huge contributor to carbon in the atmosphere is poor land use. For example, forests are cut down, poor agricultural practices destroy soil, cows produce lots of methane (another carbon based greenhouse gas), all of which lead to the carbon stored in these places being released to the atmosphere. Industrial processes can also add carbon to the atmosphere. One such process is the production of cement. Cement is made by heating rock (limestone) that is high in carbon, leading both to a useful product as well putting more carbon dioxide into the atmosphere. The sum of these activities cause the amount of carbon in the atmosphere to rise at rates that have seldom, if ever, been seen during the history of the planet. Today, in the winter of 2018, the amount of carbon dioxide in the atmosphere has risen by a third, to 405 ppm. Current human activities are causing a continued 1 ppm increase each and every year.

Now, the biggest reason that all of this extra carbon in the atmosphere is a problem is due to the greenhouse effect. The basic analogy of the greenhouse effect is that the glass walls of a greenhouse trap some of the energy from the sun, allowing the inside of a greenhouse to be warmer than the air outside. It turns out that the earth’s atmosphere does the same thing. An enormous amount of energy from the sun hits the earth, with some staying and some bouncing back into space. Carbon dioxide and other greenhouse gases in the atmosphere do the same thing as the glass in the greenhouse walls, they trap heat inside. The more greenhouse gases in the atmosphere, the warmer the earth stays. This has mostly been a great thing for life on earth, as the greenhouse effect is the reason that we have such moderate temperatures today that life on earth is so well adapted to. As mentioned in the last paragraph, carbon dioxide in the atmosphere has risen by a third, and this has trapped more heat through the greenhouse effect. So far, this rise in atmospheric carbon has increased the earth’s temperature by nearly one degree Celsius. If current trends of humanity’s resource and land use continue, this could reach 5 or 6 degrees Celsius (10 degrees Fahrenheit) by the year 2100. Humanity now stands at a point where we are cooking ourselves out of house and home. It is impossible to predict all the effects of this warming, but we do know that it would be catastrophic. Sea levels would rise, weather extremes of flood, drought and wildfire would increase, some ecosystems would collapse and many species would go extinct, and there would be millions of climate refugees fleeing these effects.

Put all together this makes for a very simple goal in fighting climate change, though it will be difficult and complex to achieve: humanity needs to stop putting excess greenhouse gases into the atmosphere if we want to save ourselves and our planet.

A few groups that are working hard to change our trajectory and to stabilize the climate include:

  • Drawdown. A comprehensive guide to all of the things that human society could do to reduce climate change through 2050, including how much they would cost, and how much they would reduce emissions.
  • An advocacy organization that seeks to stop use of fossil fuels, build renewable energy, and other activities in order to attempt to return atmospheric carbon to a safer level, 350 parts per million (hence the name of the organization).

Some thoughts on architectural and interior design

First published 4/8/16

From the very beginning of our house building project, I had a lot of ideas about what I wanted to accomplish with the architectural style as well as the interior layout and design. While I think that I would have ended up with mostly good choices by working it out by myself, the assistance of our architect Anthony Mach was invaluable. Even though I had a much clearer notion than many people do going into the early phases, I still often needed that access to an expert opinion about what is doable and how to make all of the parts fit together. And don’t even get me started on the process of turning the rough sketches into final blueprints, I don’t have anywhere near the knowledge to be able to put together those technical details.

For any of you who are considering building a custom home, I would recommend that you start by doing what we did, and make a list of things that you require, those that you would like, and those that you just don’t want to do. Also take the time to look at lots of pictures, as it always helped us to figure out if something would work by finding a good example. My digital scrapbook of inspiration eventually made it to several hundred pictures. And be prepared to revise that list in the face of budget, practicalities, or even your own changing understanding. Our starting list as of the time that we first met with Anthony was the following:

  • 3 bedroom, 2 bath house
  • Nice screen porch facing the river
  • Upside-down design, with living spaces on the upper level, and the bedrooms on the lower level
  • Passive solar orientation (discussed here and here) with plenty of big windows
  • As compact as possible given what we are trying to fit in, both for energy efficiency as well as to contain costs
  • Superinsulated (discussed here)
  • Timber framed, or otherwise using lots of natural wood
  • Contemporary design with a single pitched shed style roof
  • Resilient design, using well-chosen design details and high quality components, so that house will age well over decades
  • Big stone fireplace with a high efficiency stove insert

We already had a fairly well-developed plan by the time we went to Anthony, so I feel pretty good that out of this initial list, the only item that was dropped was the large stone fireplace. It turns out that doing these the old fashioned way with larger real stones is both very energy inefficient as well as incredibly expensive. It turns out that the vast majority of the ‘stonework’ that one sees on both the interior and exterior of today’s buildings is actually painted concrete. It is relatively thin pieces of veneer that can be added to almost any wall, and the process now yields fairly realistic looking stone. With this entire project I’ve wanted things to feel as authentic as possible, and fake stone just wasn’t something that appealed to me. As the plans developed further, we realized that the simple clean lines of a wood stove and interior stove pipe were just as good of an aesthetic fit while being much better in terms of cost and energy efficiency.

Open concept living

We, along with a lot of others buying and building houses today, wanted an open concept design, with a single great room containing the kitchen, dining, and living spaces. I have heard and read quite a number of things about the growing popularity of the open concept, and it seems that there are two major drivers. The first is a greater desire for families to spend time together. With parents working more hours, kids doing more activities, families want to spend the few hours where everyone is at home together. The other trend is for increasingly casual living arrangements. People no longer want to hide away the mess of the kitchen and to eat in a formal dining room. This fits just about right with our own decision about building this way; this was always intended to be a place for the family to be together. Opening up the living and cooking spaces to each other solve all of these issues, putting everyone all in one space. We ended up with a room of 18’x38′ (680 ft 2), which has been fantastic for family time and groups up to about 15 people. We often are cooking and doing cleanup at the same time as we entertain or keep an eye on our young children.

Screen porch

A screen porch was another thing that was at the very top of our list of desired features. In our climate it may only be porch weather for four months of the year, but during that time it is the best place in the house. It turns out that screen porches aren’t all that popular here in eastern Canada, and I actually have no idea why. In Minnesota, where I grew up, basically every cabin, and many homes, have screen porches. Granted, the mosquitos are the size of sparrows there, but there isn’t exactly a shortage of biting insects here in the region around Ottawa. The bug season makes enclosed spaces awfully appealing for outdoor living throughout the wet northern temperate climates. In a lot of the modern architecture photos and articles that I’ve looked at, I often see whole walls that open to make indoor/outdoor spaces, and decks and porches seldom seem to have any bug protection. This may work in California, but that sort of design certainly does not fit well in a place where the biting insect season almost completely overlaps the warm months.

Upside-down design

Most multi-story homes have the main living areas on the main floor, with bedrooms above. In a great many cases this really does make the most sense. One can enter the house and go straight into the more public spaces, with the bedrooms tucked away up a staircase. However, it isn’t so great if your home has a view that you would like to take advantage of, as those views generally improve the higher one goes, and I don’t think that a lot of people spend hours in their bedrooms admiring the views.

In our case, we had a perfect setup to flip the house upside down. We planned from the beginning to have a walkout basement lower level, and we had tremendous views that we wanted to be able to appreciate. Pushing the house into the side of the hill also meant that it was only five steps up from the driveway to the upper level. So while I don’t think that it is for everyone, I wouldn’t do it any other way if we were building again at this site. The advantages are that we are able to really appreciate the views that our hilltop site affords, the space is much brighter, and it tends to be warmer upstairs which is a boon most of the time (and conversely, the bedrooms stay cooler at all times of the year which I appreciate when I sleep). All that said, there is one significant drawback – even with some insulation to deaden the footfalls, it can be difficult to stay asleep downstairs when there is a 3 year old running wind sprints back and forth above your head at 6:00 in the morning.

 The downstairs

Our downstairs is then taken up by three bedrooms, one full bath, and mechanicals/storage space. We kept the bedrooms to a relatively modest size, each at about 12’x12′. This is big enough to have a full set of bedroom furniture but leaves relatively little room to spare. Some people now put in massive bedroom suites, but it seems to me that bedrooms are mostly just for sleeping and not for hanging out. And just to show that I’m not entirely self-consistent, I’ve included a picture below of the windows that we put into the master bedroom. I couldn’t resist taking advantage of the view even if we don’t spend that much time in there appreciating it.

Contemporary style

There are dozens of popular styles for homes, such as Prairie, Tudor, Craftsman, and many others. Though there are some cultural and climatic reasons for choosing one style over another, the better part of the decision making comes down to aesthetic choices. Through all phases of the design process, I spent a good deal of time looking at architectural and design websites, articles, magazines, and photos. I was particularly drawn to aspects of the contemporary style, and so making the decision really came down to that appeal. To really dig into the sort of places that I found inspirational, I found even more tightly defined terms like “modern rustic” or “mountain contemporary”. These styles really have become quite popular with those who build nice houses out in the woods, fields, and mountains. Staying within a given style lends a sense of continuity to a home, from the inside to the outside, and from room to room, though there are certainly some eclectic homes that stand the test of time as well. If you search around for terms like these in architectural magazines and websites, you’ll find no shortage of examples that have a similar feel to our own place, relatively modern looking with lots of natural wood, stone, and big windows to take in the views. I just hope that in 20 or 30 years time that our choices don’t look as dated as all of the 70’s lime green, orange, and dark faux wood paneling that my parents installed when they built their own cottage back in the day.

A few of the most influential architects and builders on our aesthetic choices are the following:

  • Finne Architects. Extremely high end custom contemporary homes. They are absolutely beautiful, but I don’t even want to know what the costs are. Nils Finne and his team make a large amount of built ins, custom furniture, and unique designs for each and every project.
  • Method Homes. A prefabricated home builder. Some of their home styles are quite architecturally similar to our own final design.
  • Go Logic, particularly this passive house they built.

Use of large dimension timbers

My wife and I both love natural wood finishes, and I am exceptionally fond of the bigger timbers used in timber framing. However, in the earlier part of our own design process, I learned why there are so few timber frames being built today. First, building with big timbers is expensive. The wood costs are significantly more, but so are the costs of cutting the traditional joinery (needed before the easy availability of strong metal nails and screws). Second, it is quite difficult to insulate a timber frame building. The most common way of doing so is to build the house twice; first build the timber frame, then build another full wall and roof assembly outside of that which can be insulated normally. At the same time, the timbers are beautiful. Many people generate a similar look with false beams or wrapping regular construction lumber in naturally finished boards, but just like what I mentioned about faux stone above, I find that many of these attempts can end up looking inauthentic or cheap.

With all this in mind, we found a few places in our home where big dimensional timbers made a bit more sense, using a building method commonly called a ‘hybrid’ timber frame. The first location was our screen porch. Here, there aren’t any issues of insulation to deal with, as the whole structure is just a shell to keep out insects, with cedar floors, plexiglass lower panels to prevent anyone from falling through, and screen above. Second, we used big beams to hold the roof trusses on the big overhangs. We put 4′ overhangs around the entire home, and though there are multiple ways to support this sort of detail, we did so with large douglas fir beams, on which all of the roof trusses rest (see the time lapse installation video here for a look at the work the fir beams do for the roof). Finally we used white pine beams for the floor joists and supporting beam for the second story. We were going to need to put in joists anyway, so we decided to use 4″x8″ joists, and a 10″x12″ supporting beam. This provides a beautiful ceiling for the entire downstairs level, and should be rock-solid for the lifetime of the house.  So for the heavy beams that we included, they all serve very functional purposes, which felt like an important thing to me, that it was not simply decoration. For all of our timber work, we used simpler joints held together by screws rather than the traditional mortise and tenon joinery, which allowed all of the installation to go much more quickly.

Building for resilience:

Finally, I want to make some comments about building for the long-term. So many decisions in home building (and too many other domains as well) are made looking only at the short term. For builders, it usually makes the most sense to build the most inexpensive construction that they can get away with, and then invest more on those parts of a home that really catch the eye of the buyers, like the fancy kitchen, spa type bathroom, or big walk-in closets. People don’t tend to be very good at evaluating what is behind the final finishes, nor are they good at imagining what the future maintenance, replacement, utility bills, or other costs will be for a home. Further, people only own a given home for an average of 13 years, so any feature that doesn’t do well on the resale market is less likely to make it into the average home.

This is of course not a complete picture. The building code improves steadily, requiring constantly better insulation, air sealing, air quality and more. And there is a growing trend toward green building, emphasizing reduced energy use and healthier indoor air. Unfortunately, these are still relatively niche markets, and the average new home being built is far less than it could be.

For our own project, we built a place that we hope to never have to sell during a lifetime, and if things go really well, our kids will continue to use it well after we are gone. With those kind of goals in mind, it is much easier to think about a 50 year time frame, and to be able to justify the costs of doing things ‘right’ the first time around. If we’ve succeeded at this, we may have very little maintenance and renovation work to do on the house itself for decades to come. Only time will tell us if we succeeded. So rather than discuss all of the details individually, I just include a long list of the details that we included for the sake of long-lasting quality.

  • Steel through fastened roof. Should last in excess of 50 years
  • 4′ overhangs on all sides of the building. Reduces the exposure of the siding and base of the house to sun, rain, and snow, which should extend the lifetime of the siding.
  • Great drainage and waterproofing around the house. Should keep all water away from the foundation indefinitely
  • Poured concrete foundation rather than cement block. Much longer lasting, and much more resistant to the elements
  • Low maintenance landscaping and plantings, should require little to no watering or fertilizer.
  • Cement board siding. Though after learning more, I would likely go with steel siding for the entire building. Steel has the same pros of fire and pest resistance, but has lower embodied energy, lasts longer and is more easily recycled
  • Real wood (white pine and sugar maple) for the trim, flooring, staircase and wooden interior doors. These should last much longer than hollow or fiberboard materials and can easily be refurbished rather than replaced if they receive any abuse
  • Low and zero volatile organic compounds (VOCs) in all of the paints and other finishes. These allow for much improved air quality, and I expect to see indoor air quality standards to become much more strict than they are today
  • Superinsulated, most insulation being mineral wool (Roxul)

Energy model of the house

First published 3/15/16

We didn’t originally plan to do any formal energy modeling for our home. It actually only came about because of our relatively last-minute decision to seek LEED certification. One requirement of the LEED process is to do an evaluation of the energy efficiency of a home, and this includes a fairly complete description of the building’s size, orientation, insulation, electrical appliances, etc. Using all of this disparate information and applying some standard assumptions about how a typical family uses a home (e.g., amount of hot showers, thermostat temperature, etc.), energy modelers are able to put together estimates of total energy use for a home.

Below is our “Home Energy Rating Certificate”,  which shows the overall estimates, including the major details about the home, the systems, and expected energy use. To boil a house down to a single number, many efficiency experts use the HERS rating. This is an evaluation of how much energy the modeled house uses as compared to a house that just meets the 2006 International Energy Conservation Code. Climate and house size are controlled for, so as to be better about comparing apples to apples. As you can see in the certificate, our home achieved a HERS score of 23, whereas the reference home is always counted as 100. While I won’t actually go through the calculation, this number is the percentage of energy that the modeled home uses as compared to the reference, with an adjustment for self-generation of power through things like our PV panels. In comparison to the ‘standard’ home, our place brings the energy demand down by over 70%.

The rough breakdowns in energy use in kWh/year are the figures that I find most interesting here. Our home is projected to use a grand total of 19271 kWh/year, with 4785 kWh coming from electricity produced by the solar panels, with the balance of 15465 kWh provided by propane.

So how does this compare to our actual use for the year of 2015 (well, November of 2014 to November of 2015)? During that time, we used exactly 400 gallons of propane, for a total of 10,800 kWh of energy. We also burned about half of a cord of maple and oak firewood, which provided roughly 3000 kWh of heat. The best measure of our solar electric use is actually the energy used by plug loads during the year, of 1400 kWh. This figure is actually a significant underperformance for our expected solar electric contribution for a couple of reasons. First, the batteries didn’t age well in their first year of use due to some overly deep discharge in their first months of service, and second, that more power was ‘wasted’ than expected, as excess power cannot be saved if it is not used and the batteries are full. I am putting together a system to use some of that excess power and will write about it once it is up and running. Needless to say, this puts our actual energy usage for the year at 15,200 kWh, much less than the model-predicted figure of 19271 kWh. This is no surprise, as we are inhabiting the home only about half of the time, and probably taking less showers and using less technological toys than the average household. I would imagine that if we were there full-time that our actual energy usage would end up quite similar to the model’s projections.

Another interesting set of details that came out of the modeling were estimates of heat loss through all of the different components of the housing envelope (See below – First document in English, followed by a more detailed one in French. Some of the text in the English is wrong in the columns but correct in the chart). To stay in kWh, I’ll work with the numbers from the French document. The total amount of heat needed from the active heating systems is 9286 kWh (25% of the reference home). Part of the reason this figure is so low is due to the passive solar heat gain coming through all of the windows, to the tune of 4306 kWh/year. Putting these figures together shows that over 31% of the total heating needed for this home is accomplished by sun streaming in the windows. I’ve taken just enough of a look at the passive solar heating literature to know that this is roughly as high as one should go with passive solar heating in a home unless one is willing to endure unwelcome overheating on warm sunny days in the winter and spring. Even with our place, I am finding that on bright sunny days in February and March that the upstairs of the house can exceed 30 degrees Celsius (86 Fahrenheit) with the heating turned off. I have actually found it to be good for the spirit to be able to open the windows and wear shorts on those blue bird days in February.

The other great thing about this heating breakdown is that it shows how much heat loss to expect from each component of the home. It is no surprise that the above grade walls are the biggest component, since they make up much more surface area than any other part of the home. The walls would have been one of the most expensive parts of the home to upgrade, due to the amount of materials needed to cover that much area. The next highest contributor is air infiltration, at 2783 kWh/year. When the house was half-complete a blower door test showed that we had an air-tightness of 1.47 ACH@50Pa, but as I outlined in this post, the house is probably tighter now and this heat loss lower than the model suggests.

The concrete slab and foundation walls, at 2314 kWh and 1435 kWh respectively, are probably the only places that I wish I would have added insulation. It would not have been that difficult or expensive to add thicker layers of rigid foam insulation, and I’m fairly sure that it would have been cost-effective to do this upgrade. I guess that one advantage of the current state of things is that the downstairs bedrooms are always cooler through the summer, making sleeping comfortable even on the hottest days of the summer without any air conditioning.

The Power of Solar

I just wanted to reiterate one more time the usefulness of both active and passive solar in reducing the need for other, usually fossil fuel, sources of energy. If we were to eliminate the solar gain through the windows and disconnect the solar panels, the model suggests that we would need 24,550 kWh/year of power from propane, or 909 gallons. However, we already get 4306 kWh of heat through the windows. The above models also don’t account for the new solar panels added this fall, which together with the original installation could produce about 9850 kWh of power per year . As I alluded to above, I am in the middle of putting together a system to use up much of this excess electric power for space heating in the winter and domestic hot water heating in the summer. If I were able to put all of this excess capacity to use, this would mean our total needs from propane drop to a projected 9074 kWh. Considering that we already use much less energy than the model projects, my hope is to cut propane use for next year from 400 gallons to 250 gallons or less. With continually improving technology and dropping prices, I can already see the day arriving, perhaps 15 or 20 years down the road, when it may be possible for us, and off-grid homes in locations like ours, to ditch the propane without breaking the bank. I’m looking forward to that day, when I have all of my energy needs met from the sun shining down from above.

So how close is our home to meeting the ‘Passive House’ standard?

One of the original inspirations for our home was the Passive House standard. I’ve discussed this a bit in another blogpost, but briefly, this is a standard for vastly reducing the energy needed to heat and power a home. That standard allows for 15 kWh/m2 of heating per year, which is quite difficult to meet for a single family home in the climate here in Ottawa, Canada. Even with all of the things that we did to build a better home, the model still suggests that we are at 47 kWh/m2 per year, so nearly 3 times the amount allowed for Passive House certification. There are just a small handful of homes that have reached this certification in eastern Canada, and some of the professionals that I’ve spoken to around here think that such a low heating requirement isn’t currently a reasonable goal in our climate. It is much colder here than in the area where these standards originated (mostly in Germany), where this number makes more sense. Here, the local homes that are pursuing certification need to have walls roughly two feet thick. We felt that it made more sense here to build a ‘pretty good’ house, and then make up some of the difference through such means as renewables. In the future, it is almost certainly going to become easier to meet and exceed the Passive House standard, as green building techniques improve and become more widely known, and as technological innovations continue to produce better products.