Solar Photovoltaic Systems

1. Description of the Technology
2. State of the Industry
3. Is a Solar Photovoltaic System Right for Me?
4. Basic Numbers
5. Benefits and Drawbacks
6. Planning Issues and Regulations
7. Setting Up and Operating a Solar Photovoltaic System
8. Additional Resources

Description of the Technology

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.

State of the Industry

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 with 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 proposed in the province.

Is a Solar Photovoltaic System Right for Me?

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.

Basic Numbers

According to the Integration of Renewable Energy on Farms website, a grid-connected system will cost $8-12/watt. Payback periods vary. Most PV systems have a 20 to 30 year warranty.

Benefits and Drawbacks

Benefits:

• Safe, clean and quiet
• Highly reliable
• Doesn't create emissions
• Virtually maintenance-free
• Can be added onto as needed
• Can be mounted on roofs, thereby not taking any farmland out of production

Drawbacks:

• High up-front costs
• Electricity generation drops substantially in the winter

Planning Issues and Regulations

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.

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.

Setting Up and Operating a Solar Photovoltaic System

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.

Additional Resources

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

Natural Resources Canada provides online solar resource maps. FarmEnergyOnline.com offers sample business plans for PV systems.

Associations

• Canadian Solar Industries Association
• Ontario Sustainable Energy Association
• Solar Energy Society of Canada Inc.