“Net Zero Energy for the millions remains an engaging, suggestive dream”

John Bentley Mays passed away on September 16^th at age 75, a man whose appreciation for art, culture and urban design played out on the pages of the Toronto Globe & Mail for decades. In a published obituary, colleague Alex Bozikovic commented, “Mr. Mays wrote around the edges of the city, interrogating the natural topography, the leftovers of past eras and forgotten periods of history.”

Mays asked if there was a large scale future for NZE homes
It is somewhat ironic, therefore, that given his love for urban design and history, Mays’ final feature in the Globe & Mail, published on the day of his death, commented on the future of residential housing, not the past. In particular, he wondered if a viable future existed for Net Zero Energy (NZE) homes on any large scale. Net Zero Energy derives its name from the design and construction objective of homes and buildings producing as much energy overall as they consume.

Related
What is a Net Zero Energy Home?
What is a Passive Design Home?

A striking new 1658 square foot house in Calgary’s NE community of CityScape built by Mattamy Homes is the first of five similar NZE residences completed this year 2016.

Mays suggested that NZE developments only occur with 3rd party financial assistance
In Canada back in 2014, the for-profit consulting group Ability Corp., Owens Corning, and Natural Resources Canada partnered in a $4.2 million NZE concept demonstration, resulting in a total of 26 NZE homes being built across the country, including five in Calgary by Mattamy Homes, five in Guelph by Reid’s Heritage Homes, and most recently four  townhouses in Kanata Ontario by Minto Communities Canada. The project has been greeted as proof that everyday NZE homes are commercially feasible.

However, as Mays observed, NZE seems to engage large scale developers only when financially supported by government and interested industry members. “Nor does it appear”, he suggested “that public regulatory regimes at the provincial and local levels are about to encourage NZE construction on a large scale.”

The extra cost for building a NZE home is generally accepted to be 15% or more, which begs the question whether NZE’s future in Canada will, for the foreseeable future, be limited to more expensive custom homes.

The number of Net Zero Energy projects under any category is growing, but hardly represents a large scale movement

Similar NZE demonstration projects have been built in the USA. Twenty homes in Fontana California were put on sale in 2015, with the promise that each would consume 60% less energy than comparable homes. There too, however, the development required assistance from the Electric Power Research Institute and the California Public Utilities Commission.

Nevertheless, Canadian engagement of NZE by developers is inching forward.  Lucchetta Homes of Welland Ontario was recently recognised for building five ‘Net Zero Energy Ready’ (NZEr) homes, under the CHBA’s Net Zero Energy Labelling Program Pilot launched in 2015, as well as Minto Communities Canada’s  NZE townhouses and NZEr homes mentioned above. However, the term ‘NZE-ready’ means in fact the homes don’t have renewable energy generation installed. The final step to NZE is an after-sale decision left to the purchaser, further indication that housing developers in Canada are hesitant to market fully turn-key NZE homes without third party compensation.

This home near Kanata is a NZEr (Net Zero Energy ready) home offered by Minto Communities Canada. Energy generation equipment is an option for purchasers.

NZE goes well beyond the energy efficiency of current code minimums and passive design
Building codes are driving the residential building industry towards increased energy efficiency. However, Net Zero Energy is a significant step beyond mere energy-efficiency and passive home design. The pay-back for the increased up-front costs for NZE must be analysed over a long period, generally 10 to 15 years, before conclusions can be reached concerning their economic benefit to the homeowner. As Greg Mella, co-director, sustainability at SmithGroupJJR, Washington, D.C says in Metal Architecture magazine, “If we are working on a conventional, energy-efficient project, operational energy savings are measured against the cost of grid-provided electricity. For a net zero project, assuming the net zero goal is immutable, you evaluate your investment in conservation measures against the cost one would pay for additional renewable energy components had those conservation measures not been implemented.”

In addition, there are a number of lifestyle issues surrounding the design and operation of a NZE home that need to be considered if their ‘immutable goal’  of Net Zero Energy can be achieved, such as the installation of appliances with stand-by power, plus the use of lighting, air conditioning, fans and ventilation systems. In other words, it’s more complicated than first appears.

John Bentley Mays leaves us with this thought: “NZE for the millions, for the time being at least, remains an engaging, suggestive dream shared by many in government and industry, in Canada and throughout the world – but a dream nonetheless.”

follow John on Twitter @john_bleasby