A solar system can provide for all the electricity needs of your net-zero home, including your energy-efficient heating and hot water systems. Courtesy David Dodge
Oct. 05, 2017 | David Dodge and Scott Rollans
Deep energy retrofitsAre you living in your future net-zero home?
Have you ever dreamed of living in a net-zero home? According to Peter Darlington, that dream might be closer than you think. In fact, you might already be living in your future net-zero home.
Darlington runs Solar Homes Inc., a Calgary company specializing in renovating existing homes into net-zero homes, which produce as much energy as they consume. Net-zero might seem like a remote, ambitious target, but Darlington insists it's more attainable than you might think. In fact, his first green renovation project was on his own 1980s-era home.
"It's really quite simple to do," said Darlington. "You can just add some insulation, some solar panels, and you can have a home that doesn't require fossil fuels anymore. It's much more comfortable. Cost you less to operate. And it's really a pretty good return on investment."
Darlington worked as an exterior contractor for more than 20 years before he realized he could be doing so much more. "I believe that climate change will be the greatest risk or challenge that my children will face in their lifetime," he said. "And I don't want to look back and have my children ask me, 'why didn't you do anything about it when you knew how to?'
"I started with an online course through Heatspring offered by a gentleman named Mark Rosenbaum. It was a 40-hour online course, it talked all about energy modelling heat pumps, different mechanical systems and air tightness."
Long before Darlington started Solar Homes Inc., he completed a net-zero energy retrofit on his own home as proof of concept.
To get your home closer to net zero, Darlington outlines four key steps, and stresses that you don't need to do them all at once.
Get an energy model done for your home
First, get an energy model done for your home to prioritize the stages of your project. This is critical because it tells you how much insulation you need, how much of a difference windows make, what size of heating system you require, and what size of solar system is needed to power your home.
Add insulation, air sealing, siding and efficient windows
Then you will probably start with an exterior renovation, adding insulation and triple-paned windows, and then improving your overall air tightness. This will cost about $30,000 for the insulation, improved air tightness and siding, and about $15,000-20,000 for windows.
"There are lots of people in Alberta spending $50,000 or more on cosmetic upgrades to their buildings. Why not spend a little bit more? Unlike a conventional renovation, a net-zero upgrade will save you money every year for the rest of your life." - Peter Darlington, Solar Homes Inc.
Upgrade your mechanical systems
As your furnace and water heater wear out, replace them with electric heat pump models (furnace and water heater) and add a heat recovery ventilator to provide pre-warmed fresh air to your tightly sealed home. Mechanical upgrades will cost about $15,000.
Add a solar system
Finally, add a solar array that is large enough to provide all your electricity needs, which now includes your heating and hot water systems. If you require a larger solar system – about 10 kilowatts – it will cost about $30,000.
"All these things can be done individually, so that you don't have to bite off this massive capital cost right up front," said Darlington. "We put 10-kilowatt solar on the garage and that generates about 90 per cent of our annual requirements."
There's never been a better time to think about going net-zero. The provincial government currently offers rebates for insulation, windows and solar that can add up to almost $15,000 for a home that is being renovated to net-zero specifications.
"There are lots of people in Alberta spending $50,000 or more on cosmetic upgrades to their buildings. Why not spend a little bit more?" said Darlington. "Unlike a conventional renovation, a net-zero upgrade will save you money every year for the rest of your life."
One of the biggest savings came when Darlington said goodbye to his natural gas bill. "It may not sound like a lot, but the distribution and connection charges for the natural gas are fairly significant and add up to, you know, $600-$700 a year," he said.
According to Darlington's estimates, you could bring a typical home close to net-zero with an overall investment of roughly $95,000. Current rebates on windows and solar could knock $10,000-$15,000 off that total. Best of all, the money you spend just might help you sleep better at night.
"Aside from the obvious return on investment, there's not a lot of chances in life to invest money in things that not only make your home more comfortable and bring down your operating costs, but are also morally correct," said Darlington.
Renovating old buildings has so much potential to reduce emissions the Netherlands has started an ambitious project called EnergieSprong to renovate every single building in the country to net-zero by 2050.
This is Part Two in the Green Energy Smart Homes series. Visit greenenergyfutures.ca to see the video and podcast that accompany this story.