Drake Landing Solar Community in Canada could be the world’s first system to deliver 80% of the community’s space heating requirements from solar energy.
The 52 homes use 800 solar collectors (2293 m2) mounted on interconnected garages and breezeways, to capture heat for storage in a borehole field under the local park. During overcast days in winter, the stored thermal heat is extracted from the borehole field.
The borehole field is at a depth of 2 m, and consists of 144 holes drilled 35 m deep. Its underground area is 35 m in diameter and 35 m deep, which can store 80ºC water in two large water tanks of 120,000 litres each.
The district distribution system delivers solar energy to the 52 homes via heated water in underground, insulated pipes. Each home has an air handler instead of a furnace, where the heated water is circulated through a fan coil converting it to warm air and distributed through conventional forced-air ducts.
Each homeowner sets their own thermostat for individual comfort.
Solar heats space and water
In addition to the solar space heating system, each home includes an independent two-panel solar thermal hot water system to meet 60% of its domestic water heating demand.
Each home is certified to R-2000 standards (the first R-2000 subdivision in Alberta) and registered with the Built Green™ programme at the Gold Level, its highest standard. The numerous energy innovations include superior insulation and air tightness, low-flow plumbing fixtures, advanced appliances and low-impact landscaping.
The Drake Landing project is on track to achieve its goal of providing more than 90% of its heating needs from its solar-powered district heating system by its fifth year. It will reduce GHG emissions by 5 tonnes per year per house (including the combined benefits of solar and energy efficiency), which translates into 260 tonnes per year for the entire community.
“This project is an excellent example of Canada’s leadership in developing and implementing innovative solar energy technologies,” says local politician Ted Menzies. “By supporting clean energy projects like Drake Landing, our government is reducing our GHG emissions and creating clean energy jobs.”
Funding from numerous partners
Natural Resources Canada provided C$3.3 million in funding to design, build and monitor the project, which was built three years ago in Okotoks, south of the oil city of Calgary.
ATCO Gas is the operator and part-owner of the heating system, and other partners include the federal Technology Early Action Measures (contributed C$2m), the Federation of Canadian Municipalities’ Green Municipal Fund (C$2.5m), the provincial government of Alberta’s Innovation Fund (C$625,000), Sustainable Development Technology Canada (C$1m) and Alberta Environment (C$500,000).
The Solar Community has received several awards, including the Emerald Award for Climate Change from the Alberta Emerald Foundation, and the Gold Award from the International Awards for Liveable Communities programme, endorsed by the United Nations Environment Program. One of its partners, Sterling Homes, was presented with the Sales & Marketing Industry Achievement Award for Best New Idea by the Alberta Home Builders Association.
Okotoks is one of the top-ten locations in Canada for solar insolation, and receives almost as much solar energy as Italy and Greece although its winter temperature can drop to -40ºC.
Internet monitoring site to go live
The town of Okotoks has launched a live internet site which will display the performance of the solar collection and storage system. The site provides realtime data for solar energy availability, the amount of solar radiation collected, ambient temperature and the heat put into the district heating system, as well as showing current temperatures of the energy storage tanks.