The Mystery of Home Solar Installation Revealed

Did you know that home solar technology has been widely available since the 1960’s? Yet in spite of its wide spread use, it is still a mystery to many. We will try and debunk the myths and shed some light on the process to show how easy it is to get into solar.

Solar is a “scalable technology”. That means a solar installation in Sacramento can be adapted to almost any application from a portable solar panel to large scale utility solar installations.

The benefits of home solar cover many areas, but key to a homeowner’s consideration, is the solar installation cost plus financing interest rates, creates a positive monthly household cash flow. What that means if your utility bill averages $250 per month, the cost of a solar installation plus the interest to finance it is substantially lower. That puts money back into the home to be spent on things like, how about a savings for your children’s college fund?

Let’s suppose you save $100 every month by installing solar in your home over your utility bill which includes the monthly investment to pay for the system. And let’s also assume you invest that $100 per month extra solar savings into a stock index fund that earns an average return of 8% per year. Let’s also suppose the amount you save increases by 3% per year to account for the national average increase in utility rates which is actually 5 – 8%. In 20 years, you will have put away a minimum of $65,000 towards your child’s college education thanks to your investment in solar in your home. Since solar panels from a reputable company are guaranteed for 25 years, by most peoples standards, that makes a sound investment.

The facts are very few investments have as high a return than a custom designed solar installation on your home. It is not unusual, when we do a home solar evaluation in Sacramento or any of our Northern California locations, to see a 15% ROI. One word of caution though, one of the caveats of hiring solar installers and getting your money’s worth is the solar system must be properly designed and installed.

To properly evaluate a solar installation the first consideration is your homes solar irradiance. How much average sun you receive at your location depends largely on the latitude of the property, slope and angle. Solar modules are activated by visible light.

When it comes to evaluating residential or commercial solar, brighter is better, clearer is better, cooler is better and higher altitude is better. Solar irradiance and watt hours per day are factored in the solar evaluation software by zip code which takes into account a 30 year history of high and low temperatues, wind and snow loads.

How much energy will my solar array generate? Solar panels are commonly rated by an industry standard known as STC or solar panel “Standard Test Conditions”. The problem with STC ratings when calculating solar for a residential or commercial system, are the tests are conducted under laboratory conditions.

In other words, solar STC standards are good for evauating the different solar panels but not so good for predicting how much energy a solar array will produce on a home say in Sacramento CA.

To get to the solar output in Sacramento, the California Energy commission has come up with a tougher standard called PTC tests which means PV-USA Test Conditions. What’s the difference? The fundamental difference is the PTC test conditions use a higher temperature and add in wind to the engineering factors for the solar panel standard. Some pretty smart folks feel this represent solar performance real world conditions and better represents what you might expect from your home solar installation.

In the next Sacramento California solar blog, we will pick up on the fit and size of a residential solar installation.