Having done everything you can to build energy efficiently, reduce embodied energy and to buy local you can now, cost effectively, consider renewable energy technologies.
The most cost effective renewable energy technology is passive solar energy. Every south facing window (without significant shading) provides significant renewable energy for free. Upgrading to high performance Passive House Standard windows will increase the passive house performance of any building. Even north facing windows with no practical solar gain will benefit from Passive House windows. They seem expensive at first glance but their superior performance and quality make them the best investment any home owner can make.
After passive solar the most cost effective system is one for Domestic Hot Water (DHW). A high performance house will consume more energy heating water than heating the living space. Reduction of this load become a priority. Fortunately solar domestic hot water are now common and their quality has vastly improved. A small solar DHW system is now very cost effective and should be the first active renewable technology employed in most homes.
Most other renewable energy systems tend to be costly and maintenance intensive. Photovoltaic solar panels create electricity directly but are still one of the most expensive renewable technologies. There is also significant debate over how much energy is consumed during their production. Some say for half a solar panel’s life it is just replacing the energy used during production. Others say it is much lower. Either way embodied energy must be considered when choosing any renewable energy technology.
Other renewable energy technologies are wind, hydro and bio-mass.
Wind tends to most efficient in larger scale wind turbines. It might be more responsible to buy power from a community supported wind project than to install one on every individual home. I hope future Net-zero standards will include the option for home-owners to support such projects.
Micro-hydro is a great option if there is an appropriate local resource. It can be expensive to install (to provide freeze protection) but long term costs will be very low and maintenance is minimal.
Bio-mass is a renewable energy technology that should be considered with great caution. Our forests are already over harvested using destructive clear-cut techniques. Reducing the bio-mass left on the ground will further hinder the re-generative abilities of our forests. Turning food producing lands into fuel producing lands may be lucrative for farmers and oil companies but it could be devastating for our collective ability to produce nutritious and low cost food for everyone.
A better option would be to use forest and agricultural products to reduce energy as this also ties up carbon in the process. In New Brunswick there are many opportunities to shift forest production toward sustainable, value added forest products. For this shift to happen the rules regarding crown forest stumpage allocation need to be revised to allow for innovative new partners to enter the market. Currently large well established industry players control most of the crown forest allocations in New Brunswick. Not allowing new players to come in with new and innovative products stifles the economy of New Brunswick for everyone.