You may have heard recently about this thing called solar power. You may have heard, for example, that a solar home energy system can cut your electric bill. You may have seen offers to go solar for zero down. Or maybe a friend told you that solar rebates, tax credits and other incentives can combine to significantly reduce the cost of installing solar panels. There’s even a chance you’ve heard that solar panels are dishwasher-safe.

All this sounds great, to be sure. And rest assured that everything you just read about solar power is true (save that bit about panels being dishwasher-safe…). But we understand that it’s sometimes difficult to make sense of what, exactly, a solar home energy system can do for you.

To shed some light on the matter, we’re sharing the following map, courtesy of the Solar Energy Industries Association (SEIA).

U.S. Solar Energy Potential Map

As you may be able to guess from the title of this post, the map offers a general overview of how many kilowatt-hours (kWh) will be generated over the course of a year by one kilowatt (kW) worth of solar panels. Got that? A homeowner who installs a 1-kW system in New Jersey, for example, could expect to generate 1,600 kWh over the course of a year. According to the map, that same 1 kW of solar could generate as many as 2100 kWh annually in parts of Arizona, or as few as 900 kWh if installed on Alaska’s Aleutian Islands.

Big deal. Chances are that you use WAAAY more than 2100 kWh over the course of the year. For reference, the average American household uses about 11,000 kWh each year. (Hint: you should take this opportunity to dig up a recent electricity bill to see how many kWh you’ve used over the past 12 months.) Putting the map in context, even that impressive output figure from Arizona — 2100 kWh/year — would meet just 19 percent of the average American household’s electricity needs. The corresponding figure in New Jersey figure would be just over 14 percent. Not that interesting — you don’t see many ads for solar energy screaming, “Install solar power and cut your bills by 14 percent!”

So why is everyone acting like solar energy systems are the best thing since sliced bread? Well, as you may have guessed, no one installs just one kilowatt of solar panels. You install as many as you can, taking in consideration a number of constraints: (1) your average annual electricity usage, (2) your budget, and (3) the amount of usable roof space, if you’re thinking about installing a rooftop solar system. Solar installers will weigh these factors, along with a number of others, when they design, propose and (ultimately) install your home solar power system.

Please note that the above map provides general overview; there are always small, site- and system-specific factors that will influence the performance of a given solar energy system. A good solar energy installation proposal will clearly present post-solar savings, cash flow, payback and return on investment.

To review: when all goes well, a solar home solution will provide fairly compelling electricity savings. In New Jersey, a 5-kW solar panel system — a size that’s much closer to the U.S. national average — would generate roughly 8000 kWh, enough to offset the typical U.S. electric bill by 72 percent! Assuming an average cost of electricity of 17 cents/kWh, that represents an annual savings of $1,360 — serious moola.

If you’ve got questions, please post them below — or feel free to contact us at (800) 265-3646. And, if you’re just starting to look into solar power for your home, be sure to check out this post.