Solar Power Costs

HOW MUCH DOES A SOLAR POWER SYSTEM COST?

There is no simple answer to that question.  Many different things affect the price.  How many solar cells are you installing?  How much sunlight does you home get a year?  Are you installing an off-grid (cut off from the local power grid) or on-grid (connected to the local power grid) system?  How many batteries are you installing?  Are you having the solar power system professionally installed, or building it yourself?

Solar power systems can cost between a few hundred dollars for a small, single-battery system intended as an emergency back-up power generator, to hundreds of thousands of dollars for solar power systems designed to provide all the energy for a large house.

CAN A SOLAR POWER SYSTEM SAVE ME MONEY IN THE LONG RUN?

Yes.  A solar power system, however, is a long-term investment with a very high start-up cost.  A professionally installed system big enough to power your entire home could cost as much as $200,000.  However, if you subtract the cost of you monthly power bill, a solar system will eventually pay for itself over the cost of thirty years. 

Also keep in mind that you get a tax break for installing green energy technology, improve the value of your home, and can sell surplus electricity back to the power companies.

WILL SOLAR CELL PRICES COME DOWN?

Solar cell prices WILL eventually shrink.  As customer demand increases, more companies will pop up to meet that demand.  As mass production capacity grows and the supply increases, economies of scale will lower the per-item cost.  Competition will kick in, keeping prices down.

Even more exciting, advances in solar technology are projected to increased the efficiency of solar panels by 1000%!

HOW MANY SOLAR CELLS OR SOLAR PANELS DO YOU NEED?

The simple answer is as many as you want or can afford.  When most people ask this question, however, they mean, "How many do I need to power my entire home?"  The answer depends on many factors, including how much energy your home uses and how much sun you get in your geographic location.

Assuming you live in a sunny area (such as the American Southwest) with at least five hours of sunlight per day, you can use this formula to determine how many square feet of solar panels you need to power your home.

• Although it varies by manufacturer, let's assume for the sake of discussion that solar cells produce a conservative average of 1.5 kilowatt-hours (kWh) per square foot per month.
• Get your power bills for the last year.  Average your kilowatt-hour usage together (add your kWh usage for each month together, then divide by twelve).  This is your average kWh energy usage per month.
• Divide your average monthly energy usage by 1.5 kWh (the amount produced by 1 square foot of solar cells per month).  This will tell you how many square feet of solar cells you need.

For example, lets say your home use 450 kWh per month.  430 kWh divided by 1.5 kWh is 300.  This means you would need 300 square feet (or 43,200 square inches) of solar cells to power you home for a month.

CAN I SAVE MONEY BY BUILDING IT MYSELF?

You can always save a lot of money on construction projects by providing your own labor, especially if you already have all the tools you need. 

On the other hand, keep in mind that working with electricity is inherently dangerous.  Mistakes can permanently damage equipment, start fires, and badly shock a person.  If you build your own solar power system, it's worth the money to have a certified electrician inspect and approve the system before you turn it on.