Natural Elements, NRCan's Monthly Newsletter
Innovative Solar Technology Showcased in State-of-the-art Building
Made in Canada combined solar heat and power system on the new John Molson School of Business building at Concordia University in downtown Montreal.
In the first demonstration of its kind, a combined solar electric and thermal system has been integrated into the daily operation of the new John Molson School of Business building at Concordia University in downtown Montréal, Canada.
Developed in partnership between Natural Resources Canada (NRCan), the Solar Buildings Research Network, Day4 Energy, Conserval Engineering and Sustainable Energy Technologies, and funded by the Technology Early Action Measures Program, the project is truly a Canadian development.
Consisting of 25 kilowatt-peak (kWp) photovoltaic modules that produce electricity and also up to 75 kWp of heat, the combined solar panels are part of a 288-square metre SolarWall® system that covers the top two south-facing floors of the building. This technology is expected to produce enough electricity and heat energy to significantly reduce the energy needs of this innovative building.
This potential result would mark a significant advance in attempts to reduce energy costs and the environmental footprint. To achieve these reductions, buildings are a good place to start. Energy consumption in the buildings sector contributed to 14 percent of Canada’s greenhouse gas (GHG) emissions in 2003. And buildings are ideal for housing energy systems because usually all the energy that is produced is consumed on site, eliminating the extra costs and inefficiencies of energy transport.
View of the John Molson School of Business at Concordia University from street level, downtown Montreal.
A large institutional structure is well-suited for this type of technology, since it is less likely to stand in the shade of neighbouring buildings. When installed on the building face that receives the most light, the combined solar electric and thermal system can then function at the highest possible rate of efficiency.
The solar technology was developed for maximum efficiency. Normally, the photovoltaic panels, which transform sunlight to electricity, convert about 15 percent of light into direct electric current and release the rest as heat energy, which escapes from the back of the panels. This loss of heat energy to the environment is clearly wasteful.
“So one of the key innovations of this project was to design, develop and demonstrate an innovative technology that would optimize the harvesting of solar energy,” says Josef Ayoub, Senior Energy Science and Technology Planning Advisor for the Integration of Renewable and Distributed Energy Sources with NRCan’s CanmetENERGY research centre located in Varennes, Quebec.
The solution is the photovoltaic/thermal (PV/T) generation system, which takes most of the wasted heat energy and uses it to preheat the fresh air drawn into the building’s heating system. The contribution of this otherwise lost energy is substantial: on sunny days, the temperature of the outside air can be raised by 20 degrees Celsius.
This technology is especially useful for institutional buildings in cold climates, such as Concordia’s new building, since fresh air is always required for ventilation and must always be heated in winter. In the summer months, the recovered heat energy can be used to heat the building’s water.
As for the electricity created by the photovoltaic panels, this is channelled into the building to reduce electricity costs. And by conducting the heat away from the back of the panels, the efficiency of the system can be further increased by as much as 5 percent on very sunny and warm days.
As well as serving many practical functions, the combined solar electric and thermal system provides a monitoring facility for research on energy-efficient buildings. A display in the lobby of the Concordia building offers students and the public a view in real time of energy being captured from the sun and a glimpse into the future of energy-efficient buildings.
To learn more about CanmetENERGY’s work with building-energy consumption and clean energy solutions, visit www.canmetenergy.nrcan.gc.ca.