Net Zero House

We toured a net zero house in Calgary. The house was built in 1984, and fully renovated a year ago.

They re-insulated the outside, with a spray-on vapour barrier and 4″ of insulation, coated with a finish. The windows were replaced with triple-paned windows.

The gas furnace was replaced with a heat pump, and a second heat pump for the new water tank. They hooked up to existing electrical, duct work and plumbing. The heat pump can heat or cool, but they rarely use air conditioning, as the house doesn’t heat up much in the summer.

Solar panels were installed on the garage roof. The panels produce more power than the house uses in summer, and is fed back into the grid. In winter, they buy power, at the same price as they sell it. They pay a monthly fee for the meter and access to the grid. In their first year they produced slightly more power than they used.

They expected the project to pay for itself in 25 years, but with the Alberta carbon tax coming in 2017, that payout will drop to perhaps 15 years, and continue dropping as power prices climb.

Next, they want to install another set of solar panels on the house roof, for an electric car.

We found it useful to actually see the heat pump in the utility room, with a second unit outside. The simplicity of the change from gas furnace was surprising and encouraging. We’re still waiting for some more price shifts, but we’re getting closer.

September: Transportation

Transportation is a little simpler than other topics we’ve tackled. Basically, bike, walking and transit are very good, while flying is very very bad.

Trains are good but we don’t have them here. We have freight trains, and a tourist run to Vancouver that costs more than flying, but nothing else.

Flying is one of the worst ways to spend our carbon-dollar. First, it takes a lot of fuel to fly a plane. Second, “the fuel is burned at an altitude where it has, as a best estimate, nearly twice the climate change impact that it would have had at ground level.” (Mike Berners-Lee, How Bad Are Bananas, p. 60, Greystone Books, 2011).

Any alternative to flying is better. Of course, sometimes that’s just not viable, especially in a huge country like Canada, or for international travel. We’ll be checking out carbon offsets the next time we fly, our personal carbon tax on flying, until there’s an actual carbon tax on flying.

We do walk, use transit and bike. We could/should/would do more. We’ll work on that.

We have two cars, which in itself is a big carbon hit, before considering any mileage. We’re not quite ready to shift back to one (we were a one-car family for many years). Our mileage has always been low, although that’s changing a little now. We head into the mountains once a week, and our parents live on the edges of Calgary, far from our central location, and far from each other. It looks like our mileage will be about 30% higher this year.

Our 2007 Honda Fit and 2010 Mazda 5 rate “Superior” on, the top rating, and were both best in class. search page. The Fit is rated at 7.3 Litres/100Km in the city, and 5.8 on the highway. Our measured mileage on the Fit was between 7.0 and 7.9 l/100Km, which is pretty good as we mostly drive in the city. The  Mazda is rated at 10.7 in the city and 8.4 on the highway. We’re not faring as well here; our actual mileage is between 11.5 and 14 l/100Km. The very best conventional cars are at the 7.0 l/100Km mark, so we are doing very well with the Honda. The hybrid Toyota Prius is rated at about 5.4 in the City. Natural Resources Canada’s guide.

Fuel efficiency can be boosted by up to 30% with simple maintenance and some driving changes. These include avoiding aggressive driving, as fast acceleration and deceleration both waste fuel. Watch highway speeding, as fuel consumption is up to 20% higher over 90 km/h, depending on the vehicle. Avoid any idling more than 30 seconds, except to clear the windshield in cold weather. Avoid driving in heavy traffic as much as possible. This both speeds up the trip, and doesn’t slow down other people, so there’s a double carbon gain. Make sure tires are inflated correctly, and vehicles well maintained. Plan trips for efficiency. For more details, there’s a good list at

We’ve decided to try to improve the efficiency of the Mazda. For a month or so, it’ll be used only for city driving, to make the test clean, and driven only by Mark, who will try to develop more efficient driving skills. We’ve read this can improve efficiency from 10-30%. Mark will take a Natural Resources Canada on-line course on efficient driving.

Our vehicles are 6 and 9 years old. We typically replace cars around 12 years, when they start to become less reliable. That’ll be when we take a close look at alternatives.

At the moment, a fully electric car sounds brilliant for city driving, but we wouldn’t take it into the mountains. Calgary to Jasper is 412 km, and we drive it in one day. We can’t get there on a single charge. Someday there might be enough charging stations. Today is not that day. At the moment there’s only one gas station between Lake Louise and Jasper, a 232 km run. We won’t drive into the Canadian Rockies and risk running out of fuel. That’s just not safe.

We could have an electric car for city driving and a gasoline car for road trips, but that seems foolish. A hybrid might make more sense for us. We’ll keep watching the rapid and exciting developments for electric cars, improved batteries, solar roofs on electric cars, and dropping prices, and make the move when it’s time to replace a vehicle. Here’s a great article on the shifting cost of clean cars. NPR: It may not cost you more to drive home in a lower emission car.

Perhaps the most important thing we can do is to advocate for a healthy carbon future, including voting for those who support mass transit.

In October we’ll be digging in to food.


August: Odds and Bits

In August we worked on odds and bits related to previous months.

Natural Gas

We’re digging through a list of repairs: insulation, cracks in the walls, leaks around windows. We’re hoping for a payoff this winter, with a better-sealed house.

We turned our water heater down one notch. It was fine. Two notches and we still had hot showers. With guests coming we debated turning it up then decided to leave it as is and test on the visitors. It was fine. When they left we turned it down again, and that’s when the cold showers started. We now know exactly the lowest setting to leave it on, except when we turn it right down when we’re away.


We had a 5% drop by April, followed by a huge spike, reflecting Maureen’s need for filters and air conditioning in the summer. We tested each filter and swapped which rooms they’re in, so the most efficient is the most used. Except we forgot about the filter in the basement that runs constantly. We’ll check that one, too, and swap it for something most efficient, if it’s an old one.

There was another spike in winter. We wondered if it was more than just weather related. Christmas? Last year we had no house guests, and surely we don’t bake enough to make a difference. We tested our Christmas lights and found an insignificant load. Still, we’ll switch to solar lights for outdoors when our LEDs die, and we got rid of our old incandescent strings.

We’re washing most of our laundry in cold water, and have noticed no difference whatsoever in the clothes. They’re still clean enough.

We rejigged some power bars. The stereo is now kept powered down (it was the biggest ghost power drain).

We turned off everything while we were away. The neighbour watching our house texted it was hot and he’d cranked up the air conditioning. “No, no!,” Mark texted back. “We’re trying to keep our power use down!” “Just giving you a carbon scare,” the neighbour replied. So that’s a thing now – carbon pranking. Thanks Terrance.


We still find lights left on. That’s our mindfulness practice – noticing. The halogen spotlights in the kitchen are starting to die, so we’ll switch them to LEDs.


We realized if our utility went to renewables, we could skip solar panels entirely. In the meantime, we’re drooling over the idea of solar roof shingles. Hopefully they’ll be a reasonable option the next time hail destroys our roof.Elon Musk announces Solar Roof Product


We planted a new tree. It promptly died. Well, not quite. Leaves died, tree’s alive. We’re watching it set out little tiny new buds, and hoping it survives.

We found some biochar. Maureen had heard about it, but didn’t know where to buy it in Calgary. Here’s the blurb on biochar from airterra.

Biochar is a high carbon content, charcoal-like material, made by heating plant matter to temperatures above 400 degrees C in a low- to no-oxygen environment. Biochar is valuable as a soil restructuring agent that enhances plant growth and health by improving the following soil characteristics: moisture retention, nutrient retention, provision of a beneficial microbe habitat, and soil pliability. Nutrients that are adsorbed onto the surface of biochar’s porous structure become more readily available to plants through an enhanced ionic exchange capacity. The introduction of biochar into soils provides a home for beneficial microbes to thrive. These beneficial microbes stimulate mycorrhizal fungi, which in turn help plants thrive through improved plant root health. Furthermore, the amendment of biochar into soils is a means by which carbon is removed from the atmosphere. This also increases soil organic carbon.

We’re trying it both as a carbon sink, and to test for improved garden growth. We worked lots into the soil around the new tree. Yes, the one that died. So – we’ll report back on how that’s going.

In anticipation of October’s focus on food, we’re getting to the farmer’s market more consistently for local food, and putting up a little for winter treats. Yummm.

For September we’ll move on to transportation.


July: Going Solar?

We’re keenly interested in generating our own power. With a reference through the Solar Energy Society of Alberta, we contacted a local company called  SkyFire Energy.

Satellite imagery of our property was used to determine the best way to install solar panels on our house. Daniel from Skyfire ran some analysis based on current electrical rates (this system involves selling all excess electricity to the utility company, so no batteries are involved.)  With solar cells on our roof, we would be able to generate 6750 kWh per year. The cost would be almost $18,000. It would pay for itself in 15 years, with a return on investment of about 2.5%. After 25 years, we would have made $13,000. (2.5% return on investment does not seem like a lot, but right now there are 10-year GICs going for just over 2%.)

We asked about the maximum potential of power generation for our property, and for about $25,000 (using our garage roof as well as the house),  we could generate more power than we consumed last year. The total estimated potential for us was 11,800 kWh (we consumed about 9900 kWh last year). This would reduce our overall carbon footprint by 40%.

The price tag is not yet economically viable for us. We’re hoping for federal or provincial support for the switch. And we’ll wait to see if prices drop further (there’s been a massive drop in price so far.) The Guardian: Solar panel costs predicted to fall 10% a year

More math: we consumed about 9900 kWh last year. With this year’s project, we’re hoping for about a 20% drop in consumption – to 7920. Panels on the roof would produce about 6750. That leaves us about 15% short. So perhaps the plan could be to wait for a government subsidy and perhaps a price drop, install panels on the roof, continue reducing our energy consumption (nail that 15%), and produce all our own power. Then add panels on the garage roof when we get an electric car.

In the meantime, we researched other options:

We could invest in a solar project. We made a small donation to The Alberta Solar Co-op.

 We’re also watching wind power – inventors are working on bladeless silent small turbines. Green Energy Jubilation: Silent Rooftop Turbine

There’s also microbial power to keep an eye on. MudWatt Microbial Fuel Cell Kit

There’s also interest in thermal heating. CBC news: Geothermal Pitched as Next Big Energy Source

We’re watching development of solar windows. We have the perfect candidate – a large, south facing garage window that we’d be happy to replace. PlanetSave: Solar Windows Ready for Production

However, none of these are in our price range yet and many are not yet commercially available.

In the meantime, we looked at solar toys. The best seem to be for off-grid living, more than for city life. We want more. Maureen has a solar calculator she bought in the 1980s that’s still going strong. The only maintenance it’s had in 30 years is the occasional cleaning of the solar strip across the top.

We did buy a new toy – a string of copper wire fairy lights for the garden. That, the solar calculator and a radiometer is the extent of solar at our house right now.

We want more! So much more is possible, like this totally solar Hutterite egg barn. CBC News: Net Zero Egg Barn. For now, we wait for technology, for government programs, and for further price drops. We’re poised to jump when the time is right. Our dream? In the next five years we’d love to have solar panels, a wind turbine on the north west corner of the garage roof, and a big solar garage window. Plus a battery in the garage, and excess power to sell back to the grid.

Next month we’ll focus on odds and bits, catching up on the repairs we still need to complete, news on small tweaks we’re trying, and a look at whether our consumption numbers are dropping yet.

June: Carbon in the Garden

June apple

Do we get credit for carbon sequestering in our garden? That was our big question for June. We have a large inner city yard with a small house, a big garage, and lots of extra city land under our care because we’re on a corner.

We have six trees, hedges and a whole lot of bushes. We grow a dozen kinds of fruit. We also grow some herbs and veges. We take good care of the soil, are organic gardeners, and prefer hand tools to power tools, including a push mower.

(For anyone wondering about what fruit grows in Calgary, we have apple, pear, strawberry, raspberry, rhubarb, gooseberry, kiwi, grape, black currant, Nanking cherry, Saskatoon berry, cherry. We pick more apples and pears than we can use each fall; the volume of the rest varies from small to none.)

The research:

A tree value study in California breaks down the significant value of trees, for carbon sequestering, help with heating and cooling, cleaning the air and beauty. California ‘Street Tree’ benefits valued at $1 Billion

But it’s hard to convert that data into anything relevant for one garden.

Our six trees calculated out to roughly 1.5 kg of carbon stored each year. We read that we can save about 2 lbs of carbon for every lb of fruits or vegetables we grow ourselves (yes, we noticed the change in units of measure to lbs. It came from a US website).

We came across some really interesting recommendations for garden carbon sequestering:

“For deep carbon sequestration, the basic requirements are as follows: Help plants maximize photosynthesis and tend the soil biology. Minimize plowing or tilling and digging, grow multi-species polycultures, don’t leave soil bare for extended periods, don’t use pesticides or synthetic fertilizer.”  Ecological Gardening: Backyard Carbon Sequestration: What Does Synthetic Fertilizer Have to Do with It?

“To store lots of carbon in your garden and keep it there, grow big trees and lots of biomass with woody stems, make sure these plants live a long time, and compost all your yard waste. Wood is the key, whether it’s in canopy trees, understory trees or shrubs.  …compost all your garden wastes on site or in your community to lock most of that carbon up in the soil for long-term storage.” The Carbon Footprint in Your Garden

Other recommendations include growing food, avoiding synthetic fertilizers, using less water/collecting rain water, and using planters and containers from upcycled materials. Oh, and let lawn clippings fall.

A garden with lots of trees is a wonderful place – we have dappled shade in the summer; light in the winter; snow on branches and places to hang bird feeders and hammocks; fresh organic food; a cooler house in the summer; an endless supply of compost; beauty and nature for the neighbourhood; a sanctuary for birds, bunnies and squirrels; and endless entertainment for passing dogs because the garden smells so interesting.

Do we get any credit?

That’s the hardest answer of anything we’ve researched. It’s brutally difficult to calculate. We’ve chosen to not claim credit, to know we’re doing well, and to look for ways we can do better.

Carbon in our garden plays out in several ways:

  1. carbon sequestered – in soil, plants, most especially in trees
  2. carbon saved because we grow some food for ourselves
  3. carbon used in inputs to the garden – plants in pots on trays, seeds in paper envelopes in a box for delivery, city water, soil additives.
  4. carbon used in what we dispose of, like plant pots and trays. We do compost everything but woody stuff (no chipper), and diseased material. Once the city sets up green bin collection that material will go to city composting.
  5. energy use in the garden – power tools, and propane for the flame weeder we use on our gravel driveway (which is permeable to water, a good choice, and we avoid chemical weed control, a good choice, but uses bad choice propane to save Maureen’s wrists from digging weeds out of gravel, which Maureen has decided is a good choice.)

What can we change:

  • we can be aware of inputs, and try to reduce them
  • we can lean even more to hand tools instead of power tools
  • we can work harder to use all the food we grow, and to share any extra
  • we can continue sharing extra plants with neighbours
  • we can work harder to remember to use rain water instead of city water

And we can enjoy our beautiful garden every day, knowing many people don’t have this opportunity to be stewards of a little bit of land.


May: Light Switches

May was all about lights. First we did our research. Tomsguide has more than we ever wanted to know about light bulbs (pricing is US).,review-1986.html

LEDs are vastly better than the alternatives, except they are more expensive. But they last forever, so it doesn’t matter unless you switch them all at once, like we did. They are the most efficient, longest lasting, and have none of the concerns about mercury (CFL) or damage to art work (halogen).

We replaced our most-used incandescents with LEDs. We didn’t replace all bulbs – this gets complicated. LEDs are not recommended for enclosed light fixtures, we couldn’t find replacement for every bulb size, and LEDs are weird with dimmers. We took the odd bulb sizes to the hardware store, and a wonderfully knowledgeable woman helped us work through the options for each. We bought 13 bulbs for $98.54. We’ll switch out halogens as they burn out over the next year. They’re more efficient than incandescents, but not nearly as good as LEDs, and short lived.

We decided to test our new LEDs using the electric meter on our house. We turned off everything but the lights, and recorded the meter disk spinning.

We couldn’t get our base consumption to zero without unplugging every device in the house, so we also measured ghost power consumption, and subtracted that number from our other measurements. As usual, our accuracy is not very. Mark liked this website for figuring out the calculations:

Our ghost power consumption was 122.3 watts. Incandescents to be changed consumed 559.8 W. LEDs in the same fixtures consumed 103.1 W, an 80% drop in consumption.

Mark made a video of our electricity meter running with the new LEDs compared to the old incandescents. Maureen laughs every time she watches what he did with it.

Press here for the video.

Between the LED lights, the drying rack, and the new freezer, we’re hoping for about a 20% drop in our electricity use.

Next month? It’s time to talk gardening.



April: Gear and Habits

In April we researched more stuff. We feel nibbled to death by wee bits of information. It is vastly complex trying to sort out personal behavior and purchasing changes. We found two really good sources of information:

book: How Bad Are Bananas: The Carbon Footprint of Everything, by Mike Berners-Lee


We’ve redone our graph to add what our appliance use would be if we had the most efficient appliances. Blue is our estimated electricity use. Red is the most energy efficient currently available, best of class, according to Natural Resources Canada:

This website is our best find of the month. If you’re looking at new appliances, start here to find the best in class in power use. As always, we’ve found the numbers hard to pin down. We’ve decided the appropriate word for our accuracy is squishy.Electrical_BestinClass

Huge improvements are possible. However – and this is the big however – a new fridge takes carbon to create, so replacing a not-ancient still functioning fridge is actually not an improvement carbon-wise. It’s better to take care of appliances, keep them running well, and replace them when they’re truly dead. Unless it’s really old, like our really old freezer. That one is worth replacing.

We found a new one, finally. It was a pain, searching. Sears doesn’t list Kwh for their freezers in-store, on-line, or anyplace the saleswoman could look. We searched on-line and found most retailers didn’t. Trail had two options, with energuide information, but neither are high efficiency. We ended up scoring at the local London Drugs which happened to have the model we wanted in stock, on sale. The new one is best of class, and much more efficient than the old one. It’s also about 30% smaller.

Our washer tested at better than best of class, even though it’s old. It’s a front loader and highly efficient.

We use a portable air conditioner on the hot days, because Maureen needs filtered cool air when it’s hot and her lungs are unhappy. We’d wondered if central air would be a better choice – it’s not. And it turns out our current portable air conditioner is best in class. We try to reduce our use of it, by shutting blinds during the day and cooling the house at night. We have lots of trees to help cut heat gain, but on the really hot days the air conditioner is working hard. The furnace and air conditioning numbers really drive home the importance of good insulation and sealing leaks.

However, the furnace fan numbers are suspect – both our current estimate and best of class. Our furnace is high efficiency and newish (installed 2013). We’re not sure what’s going on there.

The dryer, fridge, stove and dishwasher will be replaced with best of class as they die.

The other stuff we’ll pick away at where we see opportunities. We’re shuffling power bars to reduce vampire power for older gear like the stereo. We’re becoming more careful about turning off lights and looking for other ways to make small changes.

Overall: between the new freezer, the drying rack (for a 30% reduction in dryer use), and switching to LED lights next month, we’re looking at about a 20% drop in our electricity use. Switching all appliances to best of class would be about 50%. We’ll aim for that with future purchases. And we’ll keep working on other gear and bad habits. Of course, the biggest impact will be when Alberta stops using coal to generate electricity ­- this is a huge source of carbon. So advocacy is important, too.

May will be all about lights as we switch to LEDs.