Solar Photovoltaic Systems
Table of Contents
Photovoltaic panels also called solar panels or PV panels use semiconductors to convert the sun's energy into electricity.
Today's PV cells can convert roughly 15 per cent of the solar energy that hits them into electricity. Although they produce much less energy during winter, when less solar energy is available, they can still generate a significant amount on a bright sunny January day.
Panels can be either stand-alone systems or connected to the power grid. Small stand-alone PV panels are a simple way to generate electricity away from the grid: to power electric fences or pump water, for example.
To increase the electricity yield, panels can be attached to tracking units that keep them aimed at the sun as it moves through the sky.
Photovoltaic panels have been used commercially since the 1980s. Since then, efficiency has gone up while costs have come down. Expect to see more technological advances in the coming years including the development of "thin film" photovoltaics that promise to reduce costs significantly.
Millions of solar PV systems have been installed worldwide, and the technology is well established in Ontario. Recently several "solar farms" large ground-based arrays of solar panels have been installed in the province.
Solar panels can be installed on the ground or on a roof. For roof-mounted systems to work well, you'll need clear southern exposure from at least 10 am to 3 pm. The roof should face within 10 per cent of south and the slope ideally should be greater than 30 per cent.
Conventional solar panels attached right to the roof (with no adjustments to change angle) add about 5 lbs per ft of loading. An engineer should be retained to ensure the building is capable of handling this additional loading.
Grid capacity is also required to accept the power. Permission from the local electrical distribution authority to connect should be obtained before construction commences.
According to the Integration of Renewable Energy on Farms website, a smaller grid-connected system will cost $8-12/watt. Payback periods vary. Many PV systems have a 20 to 30 year warranty.
A non-tracker solar system using conventional panels will produce between 1000 to 1200 kWh per kW of panel depending on roof location and location in Ontario. See OMAFRA's Solar Electric Systems infosheet for more details.
The Ontario Power Authority facilitates the FIT program which offers a 20 year contract for electricity from renewable sources.
Prices for solar ranges from 44.3 to 80.2 cents per kilowatt hour (kWh) plus community adder of 0.4 cents per kWh may be available for larger solar systems.
The land use planning approvals process for future solar projects will be subject to the provisions of the proposed Green Energy and Green Economy Act (Bill 150). Bill 150, once it becomes law, is expected to override most Planning Act requirements that may currently apply through your municipality. Check with your municipality for clarification about which approvals process will apply in your case.
Ground mounted systems over 100 kW can not be installed on Class 1, Class 2 and Class 3 (once limits are exceeded) soils that are zoned for agricultural use. See Specialty Crop and Canada Land Inventory Mapping for the Feed-in Tariff Program page for more details.
Most installations will need to be inspected by the Electrical Safety Authority, whether they are stand-alone or grid-tied. If you plan to connect to the power grid, there are additional requirements you'll need to meet.
Small off-grid systems can be bought as commercial kits that are relatively easy to install. For more complex systems or systems you plan to connect to the power grid, working with a reputable contractor is advised.
Because many PV panels have no moving parts, there is no wear and tear and thus virtually no maintenance required once the system is up and running. You may occasionally need to clear leaves, snow, dust or other debris, and if you've chosen adjustable panels you can change the angle with the seasons to take full advantage of the sun's rays.
If you use batteries to store your electricity, you'll need to top them up and equalize them regularly.
Publications and Websites
Several helpful publications are available online: Natural Resources Canada's An Introduction to Photovoltaic Systems and Photovoltaic Systems: A Buyer's Guide, OMAFRA's Solar Electric Systems and the Ontario Sustainable Energy Association's Solar PV Community Action Manual.
For additional information, check Canada Mortgage and Housing Company's photovoltaics factsheet, the Clean Air Foundation's Go Solar website and the pages on stand-alone systems and grid-connected systems at the Integration of Renewable Energy on Farms website.
Online Maps and Tools
For more information:
Toll Free: 1-877-424-1300