Sun shines for Metro Vancouver solar system at Burnaby office
The sun, rain or shine, has been producing heat for Metro Vancouver's head office on Kingsway in Burnaby as part of a pilot project begun in December 2009.
The regional district is capturing energy from the sun to heat water is offices. Glass tubes have been installed on the roof of the 20-storey commercial highrise to collect solar heat, even when its cloudy or rainy.
Like most office towers, Metro Vancouver's has large natural gas-fired hot water tanks. The captured solar heat is stored in the tanks and added when needed to the building's existing water system, and used at washroom sinks on each floor.
A few similar systems have been installed on other buildings in the region, including the City of North Vancouver's library and Olympic Village in Vancouver.
However, Metro Vancouver's head office is one of the first highrises with the system.
"This pilot project will help demonstrate whether the use of a solar hot water system in a commercial highrise building is an effective technology to reduce energy use and greenhouse gas emissions," said Joe Trasolini, chair of the regional district's environment and energy committee.
Putting the tube on top of the building just west of Willingdon Avenue in the Metrotown area was a bit of a challenge. Since it's on the peak of a hill, the top of the building is often subjected to heavy winds so engineers and solar heating experts had to find a solution.
Instead of flat panels which might act as a sail in heavy winds, they used two-metre long tubes with an outside diameter of 10 centimetres. The tubes are spaced apart in a rack so the wind can pass around them.
The tubes also capture more energy than flat panels in the winter. On sunny days, the tubes can reach temperatures of 55 C while producing 35C temperatures on cold and overcast days.
In 2010, Metro Vancouver found that even though hot water use in the building was the same as 2009, natural gas use dropped 25 per cent because of the panels. The district estimates a greenhouse gas reduction of 4.5 tonnes, the equivalent of emissions caused by driving a mid-size car 18,000 kilometres.
The district is adding more monitors in an effort to find ways to maximize the system's efficiency.