Solar Power

Photovoltaics are the simplest form of alternative energy. There are no moving parts in photovoltaic modules and little maintenance is required.

A photovoltaic converts the sun’s energy into electricity which is either used immediately (grid intertie or water pumping) or is stored for future use (batteries). Solar electric systems are modular, allowing you to start with a small system. As your power requirements grow, you can easily add more modules.

There are many different types of solar cells available, with many new developments expected in the years to come. The whole trick to PV's widespread adoption is getting the dollar per watt lower.

Types of Solar Cells

Single Crystal

Single crystal silicon cells are extremely thin wafers of silicon cut from a single silicon crystal. These are the most efficient type of silicon cells and have a life expectancy exceeding 25 years. The cells are fragile and must be mounted in a rigid frame. You can tell it is a single crystal due to the uniform, rounded individual cells.

Multi Crystal

Multi crystal silicon cells are also extremely thin wafers of silicon but are cut from multiple crystals grown together in an ingot. They are similar to single crystal cells in life expectancy and fragility. However, they are slightly less efficient than single crystal cells and require more surface area to produce a given amount of electricity. These types of cells are usually square and will have a varied appearance.

Amorphous Silicon(a-Si) Solar Technology

Amorphous silicon cells are made by depositing a micro thin layer of silicon directly onto a sheet of stainless steel. Because amorphous absorbs light more efficiently than its crystalline counterpart, the amorphous solar cell thickness can be 100 times less, thereby significantly reducing cost of materials. By utilizing a flexible, stainless steel substrate and polymer-based encapsulates, products utilizing this technology can be very lightweight, flexible, and durable. No parts are broken during shipping and units are easy to transport to remote rural areas, thus saving on shipping costs.

Spheral Solar™

Spheral Solar™ technology is a revolutionary solar electricity technology breakthrough that provides an extremely versatile and cost-effective method of generating solar electricity. The result of over 40 worldwide patents, this unique proprietary technology comprises thousands of tiny silicon spheres, bonded between thin flexible aluminum foil substrates to form solar cells which are then assembled into durable, lightweight modules that can be applied to virtually any surface.

Global Highlights

Canada lags behind the rest of the world in PV deployment for two main reasons: Cheap power and lack of political drive to promote renewable energy in general.

What’s Happening in BC?

Currently, PV modules largest use is for remote sites that have no access to grid power. These include, but are not limited to: Radio repeater stations, Remote monitoring stations, remote homes and cottages.

As opposed to other technologies such as Wind or Microhydro, solar PV requires much less maintenance - generally limited to keeping the panels clean and perhaps a seasonal tilt adjustment.

Net Metering

The good news is net metering, or grid intertie is now permitted in BC. What this means to you, is that if you wish to install PV modules on your home or business, and feed that power directly into he utility grid, you can do so (legally). Take a look at BC Hydro's website where you can download all the information and application forms

What Does it Cost?

Solar PV modules in Canada currently retail in the $6-$8 per watt. Additional costs include "balance of system" components such as mounting hardware, wire, controllers, batteries, etc.

For many remote sites, solar PV can compete aggressively with the costs of electricity derived from conventional sources. Many sites that require extensive power line construction will find solar systems may be more cost effective. If you are spending more than $20k on power lines, you should consider PV.

For people that are on the grid, one does not currently buy solar PV for Return on Investment (ROI). There are many purchases we make that are not purchased based on ROI, but other concerns. Cars, entertainment system and furniture are generally not purchased with ROI in mind.

Environmental Matters

Greenpeace conducted an audited study of the PV production process used by Siemens, around 1999. The conclusion was the energy required to produce a PV module was recovered in approximately 14 months of use of said module.

Technical Matters

Solar PV modules require specific orientation. They need a clear, unobstructed, unshaded view of the sun for optimal performance. There are many considerations that go into the design of a solar PV system. It is suggested you contact a professional for a system design and installation.

Installation of solar PV systems is governed by the Canadian Electrical Code (CEC). One must have the appropriate permits and inspections just as with any other electrical project.

For more information:

• Solar Photovoltaic Systems - A Buyer's Guide
• BCIT Applied Research Team
  Training

Can I Use it at Home?

Possibly. Solar PV systems can be quite complicated. Installation requires a bit of roof work, some carpentry, some metal work, some electrical work. PV modules are very fragile and must be installed in the optimum location for best results. That being said, if you have taken the time to properly educate yourself on the various aspects of the installation and are competent with power tools, electricity and roof work you may have a fun project to work on.

Links

Canadian Solar Industry Association
Solar Energy Society of Canada
David Suzuki Foundation
Renewable Energy Deployment Initiative
Total Solar Energy

Credits

Written by Kevin Pegg for the BC Sustainable Energy Association, 2007.