December: Looking Back

Our goal for our 2016 Zero Carbon project was to learn, to tweak, and to make a plan for larger changes.

What we learned:

We can make a massive difference to our own carbon footprint through physical changes to our house, how we get around, and through our purchasing choices. It requires institutional change, too. For example, Alberta still uses coal for electricity generation, which increases our own carbon footprint. As coal use is phased out by 2030, our carbon footprint from electricity will drop massively.

What we tweaked:

To reduce electricity use, we replaced the freezer with a smaller and more efficient model, bought a drying rack to reduce dryer use by about a quarter, replaced lights with LEDS (for an 80% reduction in power use), and tweaked the use and arrangement of air filters.

To reduce natural gas use, we turned down the water heater, fixed leaks around windows, replaced a door sweep, and filled odd gaps. We are still working on insulting the basement where the wood of the house sits on the cement foundation, caulking behind the baseboards in the back entry, and finding a better dryer vent.

To reduce secondary carbon production, we reduced garbage and increased recycling, planted a tree which promptly died (we’ll try again this spring), changed driving habits to increase fuel efficiency, tried to waste less food, and ate more local food, and more vegan and vegetarian meals.

Our results:

The model to measure our carbon footprint we used last year has been revamped and comes up with totally different numbers, so there’s no way to compare this year’s numbers with last year’s. We do have some hard numbers for fuel use.

We thought we were driving more because of some lifestyle changes, but in fact our mileage is lower. Our total fuel use is down 17%. That’s mostly coincidental to our zero carbon project, not earned.

Our electricity use for 2016 resulted in 7.15 tonnes of carbon creation. If we were in BC it would be 1.28 tonnes. That’s the difference between more hydro vs. more coal as a source for electricity production. That means an electric car is not our next best purchase, and neither is replacing our gas furnace with a heat exchanger. Our natural gas use released 4.19 tonnes of carbon.

Our natural gas use decreased by 7%, and electricity by 12%, for 2016 compared to 2015. Many of the changes were done part way through the year. Our estimates for a full year after all changes are completed are 15% for natural gas, and 20% for electricity.

The total cost for the work was a little under $1000. A third of that was for an assessment. We deliberately looked for the easy and inexpensive changes to start with. After this, the price goes up.

What we’ll do next:

  1. We have some house sealing jobs to finish.
  1. As appliances die, we’ll replace them with best in class for energy efficiency.We’d get about a 50% drop in electricity use by switching all appliances to best in class.
  1. We’ll keep watching for developments with solar panels and solar tiles. If we get hit with a damaging hail storm, that might be when we buy, either solar tiles or panels to mount on a newly shingled roof.
  1. We’ll watch government taxes and subsidies, using them to move a little faster.

We’ve had a lot of fun with our zero carbon project, learned a lot, were constantly surprised, and are pleased with what we’ve accomplished. We’ll continue to make changes, but not to blog monthly. We’ll post irregularly, when something interesting comes up. If the work we’ve done inspires some changes at your place, let us know. We’ll cheer you on.

Maureen and Mark

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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.

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.