Building Net-Zero Homes
Funded through Round 5: SMEs Only in 2012, the Landmark Group’s project focused on designing and demonstrating affordable NetZero Energy Homes (NZEH) and NetZero Carbon Ready Homes (NZCRH) for mainstream housing. The initiative successfully constructed 19 NZEHs and 37 NZCRHs, reducing operational greenhouse gas emissions while addressing the barriers of high costs and low public awareness for future deployments.
NZEH integrates advanced energy efficiency measures and on-site renewable energy systems to achieve zero net energy consumption. Key components of this include high-performance insulation, energy-efficient windows, air-source heat pumps for space heating and hot water, heat recovery ventilators (HRVs), and solar photovoltaic (PV) systems. These homes are designed to minimize energy use for heating, cooling, and electricity, while generating enough renewable energy on-site to offset annual energy needs, thus reducing both operational costs and greenhouse gas emissions.
During the second year of the project, Landmark Groups found that for homes in a region where electricity is predominantly generated by coal-fired power plants, the most cost-effective approach to achieve this goal is to use relatively clean energy, natural gas, to heat the house and export on-site renewable energy to the grid to offset the carbon emissions caused by on-site fossil fuel use. Based on this understanding, the homes were designed, built and equipped with high-performance insulation, energy-efficient windows, high-efficiency furnace, tankless condensing water heater, high-efficiency HRV and drain water heat recovery systems. Overall, the homes built following this approach exhibited excellent energy performance, reducing 303 tonnes of CO2e emissions per year and 15.2 kilotonnes of emissions over the 50-year lifetime of the buildings.
Navigating Affordability and Awareness
Though technically successful, the project’s implementation identified two major barriers for widespread adoption of NZEHs and NZCRHs. The first barrier is the high cost of constructing NZEH and NZCRH, particularly due to the cost of energy-efficient materials and PV systems. Given this, the project focused on design optimization through energy modelling and developed energy upgrade packages to reduce costs. While these efforts reduced costs, in order for these homes to match regular home prices and make them truly affordable for mainstream buyers, the incremental costs need to be reduced by another 25 to 30 per cent.
Another major challenge was the limited awareness among consumers about the benefits of NZEHs and NZCRHs. Despite their long-term savings and environmental benefits, most buyers were not motivated to invest in these homes due to historically low energy prices and limited understanding of their value. Consequently, sales and marketing were crucial areas of development for this project. Between the time when the Landmark NetZero Energy show home opened to the public in the fall of 2012 and 2015, over 1,500 people had toured two Landmark NetZero Energy show homes in Calgary and Edmonton. About 1,000 people visited four Landmark single-family NZEHs and the NetZero Energy townhouses during the 2013, 2014, 2015 and 2016 Eco-Solar Tours. National and regional media such as CBC, the Globe and Mail, Calgary Herald, Green Energy Futures, Alberta Venture and Yahoo News have reported Landmark’s NetZero initiatives. Despite these successes, awareness and/or interest in purchasing these homes was still generally minimal by the end of the project.
What’s next?
Since this project’s completion in 2015, Landmark Group of Builders continues to advocate and advance NZEHs and NZCRHs and has established three net-zero communities in Edmonton. More recently, there has been significant growth and adoption of zero-energy and zero-carbon homes. This growth is driven by rising interest in sustainable living, government incentives, and the decreasing costs of solar technology and energy-efficient systems. Additionally, government programs encourage builders to meet higher energy standards and build to zero-energy-ready standards. These homes are designed to be more easily retrofitted with renewable energy systems in the future, helping homeowners transition to net-zero as solar and energy storage technologies become more affordable.