Solar PV - Montana Renewable Energy Association

Solar photovoltaic ("PV") panels are made up of solar cells that convert light energy directly into DC electricity. The word "photovoltaic" comes from the word "photo," meaning light, and "volt," from Alessandro Volta (1745-1827), a pioneer in the study of electricity. So "photovoltaic" literally means "light-electricity".

"On-grid" solar PV systems are connected to the electric grid, allowing you to use utility power at night or when the sun isn't shining. When your solar panels generate more electricity than you use, this electricity can flow back onto the grid if your utility has an active net-metering program. This allows your electric meter to spin backwards for a credit. Contact your electric energy provider for information about their net-metering policy.

"Off-grid," or stand-alone, solar PV systems are not connected to the electric grid, and typically rely on batteries to store the power generated by the solar system.

Want to learn more about going solar and how to choose a contractor? Check out our 'how-to' guide

What size system do I need?

This will depend on the amount of energy your home uses each month and each year. To offset most of your energy use, a "typical" Montana resident would need somewhere between a 4kW to 7kW system. This will vary depending on a number of factors, including roof angle, which direction the roof faces, available space, energy use, etc. Your solar installer will know all of the ins and outs of what system you should consider, and you should be sure to ask them. Typically, a first step on an installation is a site assessment, which includes understanding all of those physical characteristics plus information about your energy use and, importantly, your energy goals. Then, you and your installer can work through what size system would work best for you. Once you get an idea of the system size and design that will meet your needs, you can use the National Renewable Energy Laboratory's online PVWatts Calculator to estimate your energy and cost savings.

How much will it cost?

Typical residential PV system costs range from $10,000 to $20,000, including installation. However, thanks to incentives and tax credits, you may be able to reduce the cost of your system by as much as 50%. The cost of solar PV has been dropping significantly over the years, and continues to drop. You should know that the cost of your system can vary not just on the installation size (e.g. how many kilowatts you install), but also on other factors such as what type of inverter you use, what kind of mounting system is used, etc. Be sure to ask your installer about all of these options and they can recommend what will work best for you. Once you get an estimate, our friends at the Clearwater Credit Union have resources to help you determine if solar would be a good investment. Their research indicates that solar investments are often favorable, but it will depend on the specifics of the your system, financial situation, and assumptions about the future. Clearwater Credit Union put together a digestible financial analysis that you can read on their website to support your decision-making.

What incentives and tax credits are available?

There are several options for solar PV systems. Visit our Financing and Incentives page for more information on your options. You should also learn about how net metering will help you get the most out of your investment.

Where can I find an installer?

The column on the right hand side of this page lists a number of installers operating in Montana. These companies are all MREA members! You can also visit our full Installer Directory for an interactive map of installers.

Where can I find more information?

Be sure to check out Part 2: Solar Financing!

Photo credit (this page): Lincoln Electric Co-op