Surprisingly, Massachusetts is one of the best places in the country to install a rooftop solar photovoltaic (PV) system, due to solar-friendly policies, generous financial incentives, and the relatively high cost of electricity. This article offers ideas on issues that impact your solar project.

Most solar companies offer both purchase and lease programs. Lease programs offer a way to install solar with zero out-of-pocket expense, in return for discounted electricity. While leasing certainly helps the environment, it provides only minor reductions in electricity costs and lessees don’t benefit from financial incentives offered to system owners. If you can afford the initial cash outlay for purchase and can use the available tax credits, system purchase offers more benefits.

One of the biggest incentives to going solar, the 30% federal tax credit, was slated to expire at the end of 2016, but has been extended to at least 2019. This credit allows you to deduct 30% of the cost from your federal taxes in the year you put the system into operation. In addition, Massachusetts offers a $1000 credit on your state taxes.

SRECs (Solar Renewable Energy Certificates) are also available. They reduce the long-term cost of a solar system in the first 10 years of ownership and are available only to system owners. One SREC is generated for every 1000 kWh of energy produced. Each certificate is currently worth around $280, but will decrease over time. The value is based on supply and demand, and a third party is required to sell them, with commissions and fees running about 5% to 7% of the current SREC auction price. Over a 10-year planning period, a $200 average net price per SREC generated is a reasonable assumption. [Editor’s note—legislation pending at the state-house may bring some changes.]

Before making a commitment to solar, thoroughly investigate your household electricity usage by analyzing your electric bills. Reduce consumption by installing LED bulbs and setback thermostats, adding insulation, choosing high efficiency appliances, and scrapping that second refrigerator. A great starting point is a free Mass Save Home Energy Assessment.

When adding a solar PV system, try to offset at least 75% of your annual usage. Offsetting a higher percentage is better, but don’t produce more electricity than you use annually. Rarely is a property ideal for solar in every way. You won’t really know what a rooftop solar system can deliver until an engineering assessment, including a shading analysis and a preliminary engineering study, are completed. Some companies offer a production guarantee, which means that the system provider will reimburse you for electricity production that was expected, but not actually realized if production falls short of the contract goals. This gives you some assurance that production estimates are realistic and have been conservatively vetted by the system provider.

Choosing a supplier

These questions will impact the feasibility of your solar project:

• How much clear roof space is available (free of chimneys, vent pipes, etc.)?

• What is the pitch and direction of your roof (south facing side is ideal)?

• How much shade do you get? • How old is your roof?

When choosing a supplier, realize that most financial projections are based on “soft” numbers. Future electricity costs and the value of SRECs are subject to market forces, and the proposed system electricity production cannot be precisely known. Find out how long the supplier has been in business, who does the installation, how many installations they have done, and how warranty issues are handled. Solar components are very reliable, but problems can occur. Most installations come with a comprehensive maintenance package that covers all repairs for 20 years or more. But is the installer going to be around in 10 or 20 years from now? Find out how warranty issues are handled if the installer is no longer in business. If possible, get references and addresses of nearby homes where recent installations can be seen.

Make sure to ask about different panel options. Panels are made at various levels of efficiency, but more efficient panels cost more. All panels experience degradation in efficiency as they age. Understand the efficiency and degradation of the panels proposed for your installation. High efficiency might make sense if you have limited installation area.

Most solar providers have teamed up with financial institutions to offer attractive financing programs for
the purchase of a solar system. Many offer loans for the amount of the anticipated tax rebate at 0% interest for up to 16 months. Compare the overall costs of financing from solar suppliers to other means of financing, such as a home equity line of credit.

Homeowners in Massachusetts benefit from a great regulatory climate and generous financial incentives to help make solar affordable. Investigate multiple suppliers, ask a lot of questions, and choose the one that offers you the best combination of experience, components, warranty, financing, and price.

(Craig Forman holds advanced degrees in Electrical Engineering as well as an MBA. A Newton resident since 1990, he is also a Green Newton member. His solar project, including 26 rooftop solar panels, was completed in November 2015.)