Wilden Living Lab homes show significant energy savings
The results show the two research homes, which may look similar from the street, but couldn’t be more different.
After 18 months of research documenting each of the homeowner’s energy consumption patterns, the results show that the ‘Home of Tomorrow‘ uses 67% less energy than the ‘Home of Today‘, or 40.8 gigajoules (GJ) less per year. That amounts to 99% fewer carbon emissions and the carbon offset is equal to taking 16 gasoline-powered cars off Kelowna streets. As a comparison, one GJ of electricity could make 1,000 pots of coffee or keep a 60-watt light bulb continuously lit for six months.
More conclusions will be published continuously in the upcoming year. Final results are expected to be available towards the end of 2021. The Wilden Living Lab website provides a quick overview of the latest results as well as more detailed numbers and articles published by the School of Engineering, UBC Okanagan Campus. To stay on top of all findings just subscribe to the newsletter.
FortisBC’s Carol Suhan explains that the goal of the Wilden Living Lab partnership is to show the real-life comparisons in materials and equipment so home buyers can affordably build an energy efficient home. This project represents one of the many ways FortisBC is advancing its goal of lowering emissions from its customers by 30% by 2030.
“We’re thrilled with these results – our shared vision is to help accelerate the transition to carbon neutral residential living, especially in new homes. We believe it can be done competitively and affordably, and the research so far shows that,” she says.
Built by AuthenTech Homes in 2017, the ‘Home of Today’ features equipment and construction built to standard Building Code requirements. It includes a 92% efficient natural gas furnace, electric hot water tank, double glazed windows, R40 insulation in the ceiling, incandescent lighting and standard appliances.
The Home of Tomorrow, also built by AuthenTech Homes in 2017, features a ground source heat pump, solar panels, heat pump water heater, water-saving toilets and faucets, triple-glazed windows, R50 insulation in the ceilings and LED lighting. In addition, high-efficiency appliances were installed including an induction range, and Energy Star rated 5-door fridge, dishwasher, hood and bathroom fans washer and dryer.
Sensors throughout the homes have documented energy consumption and cost efficiency, and have been monitored and compared by a research team at UBC Okanagan’s School of Engineering for the past 18 months. Joining UBC Okanagan and FortisBC in the partnership are Wilden, AuthenTech Homes, Okanagan College, and Natural Sciences and Engineering Research Council of Canada.
The ‘Home of Tomorrow’ has achieved an exceptional EnerGuide rating of 47 GJ/year and is 52% more energy efficient than the ‘Home of Today’. This consumption-based rating allows homeowners to see how much energy the home uses annually, similar to how you would see a consumption rating of kilowatt-hours per year for home appliances, litres per kilometer for vehicles, or calories per serving for food. The lower the number, the better the energy performance of the home.
“That just by itself is significant savings for the homeowner in energy costs,” says Suhan.
In the ‘Home of Tomorrow’, the ground source heat pump generates almost four times more heat energy than what is put in, or 400% efficiency. The standard natural-gas furnace installed in the ‘Home of Today’ has only 92.1% annual fuel utilization efficiency (AFUE), which means it is 92.1% efficient in producing heat. Despite its high efficiency, the ground source heat pump asks for a high initial investment, which results into a long payback period. However, the ground source heat pump is the component that contributes the greatest to the reduction in carbon within the home.
Dr. Shahria Alam, with UBCO’s School of Engineering, says the research shows the payback period on several of the technologies relies on different factors. For instance, the payback of triple-glazed windows is significant but can be be reduced by incentives on the purchase price, maintenance, and installation cost.
Aside from overall energy savings and energy costs, Suhan says that homeowners will see a significant benefit around comfort levels.
“The more energy efficient home [the Home of Tomorrow] is so comfortable, the air circulation is as amazing as is the soundproofing. You can feel the difference, no question,” she explains.
Canada’s National Energy Code for Buildings (NECB) 2017 says the “most cost-effective time to incorporate energy efficiency measures into a building is during the initial design and construction phase. It is much more expensive to retrofit later. This is particularly true for the building envelope”, which is the single most important element of an energy efficient dwelling.
Suhan agrees: “Design-wise it is so important to focus on the building envelope, to make sure that it is as tight as possible.”
The next phase of the Living Lab will compare what’s called a Net-Zero ready home to the ‘Home of Tomorrow’ and the ‘Home of Today’. These homes reduce the amount of energy needed to operate and generate energy on site through alternative energy sources.
“What we have learned so far as part of this project plus the requirements in Step Code 5 will make for an incredibly efficient home,” adds Alam.
“A Net-Zero house can be more expensive to build, but overall, the total cost of ownership could be lowered because of just how efficient it is,” says Suhan. “It’s said that you can heat a [Net-Zero] house with a hairdryer.”
Incentives from FortisBC can help offset building costs—homes built to be more energy efficient than the minimum BC Building Code requirements can qualify for a rebate ranging from $3,000-$10,000 as part of FortisBC’s New Home program.