Installing solar panels on your home saves you time and reduces your carbon footprint. But many homeowners are wary of getting started, perhaps confused by the technospeak, the regulations, or the number of installers. Here’s a basic introduction to get you past that confusion.

What Are Solar Panels? How Many Do I Need?

Solar panels that provide power are called photovoltaic (PV) cells. (There’s also a second kind of solar panel called a solar thermal collector, which collects energy to heat water.) PV cells are special batteries that collect sunlight, transform it into energy, and then send that energy to an inverter. The inverter converts that energy into the electricity that powers your home.

Before figuring out how many panels you need, make sure you have a place to put them that receives direct sunlight between 10 am and 2 pm, when the sun is strongest. The more hours your panels are exposed to full sun, the more efficiently they will generate power.

The size of the system you need depends on two factors: how much energy your panels can produce and how much energy you need.

How much energy your panels can produce hinges on something called insolation: the amount of solar radiation that reaches the ground during a given period. This varies based on region, so a solar-powered home in New England will be less efficient than one in Arizona.

To find out how many kilowatts of energy you use on an average day, look at your electric bill. Multiply that number by .25, and that’s about the size of the system you’ll need. Just how many panels are required to produce that energy will depend on the output of the panel, the insolation, and the how many hours per day the panels receive full sunlight.

How Do I Decide Who to Hire?

Installing solar panels is complicated and best left to professionals. Make sure your installer:

  • Offers a strong warranty. The inverter should be covered for at least 10 years, the panels between 20 and 25.
  • Doesn’t outsource installation. If something does not go according to plan, you want to be able to directly reach company representatives.
  • Is licensed and bonded.
  • Can supply recent customer references.

How Much Will It Cost?

The price of solar panels has been steadily dropping throughout this decade. The national average up-front cost in 2014 was about $17,000, including tax subsidies.

Funding Options: Lease or Buy?

Solar leases are increasingly popular. Not only do they defray the up-front cost of installing panels, but leasing companies usually pay for repairs and maintenance. But despite the higher up-front cost, buying a permanent installation can be a better long-term investment. Leased solar panels are less likely to be covered by local tax credits, and they will not increase your home’s value like a permanent renewable energy system will.

Solar panel installation will almost certainly require municipal construction permits, which will add a small fee. Your installer will usually take care of obtaining these permits.

Notes on the Financials: 

Going solar usually raises your homeowner’s insurance premium by a few dollars a month.

Tax Breaks: Unfortunately the Federal Solar Investment Tax Credit, which subsidized solar panel installation since 2006, expired this year, though it may be renewed by Congress. Massachusetts, however, offers a number of tax credits, renewable energy loans, and other funding assistance for solar panel installation.