A couple weekends ago I had to opportunity to attend a class entitled “Do It Yourself Photovoltaics” which was put on through our local garden center. The man who taught the class, Mr. Jon Passi, stressed that his goal was to make solar power projects as accessible as possible to others, and encouraged us to share what we learned from his class with our neighbors, so I’d like to share a bit about what I learned with you.
How Much Solar Power Do You Need
The first step to getting a home solar project going is to figure out how much power you need. Most power companies these days will provide graphs of your power use for the past year, so you can see how much electricity you use each month. When you look at this graph you’ll probably see that you have a season of the year where you use quite a bit of electricity, and a season where you use less. For my family, we use more electricity in the winter time than the summer, because we are more likely to be inside, and because it is dark during more of our waking hours. But if you might find that the opposite is true for you, depending on your habits and your home.
So, take a look at your energy use over the course of a year. With solar power, you produce the amount of electricity you use each day, and then start over again the next day. Figure out what your average monthly electricity use is. Then divide that number by 30 to get an estimate of your average daily electricity use. For the average American family, this number is somewhere in the range of 20 – 40 Kwh per day.
Your average daily electricity use is what you’re shooting to produce with a home solar power project. Yes, some days you will use more, but if you’re still connected to the power grid, you’ll be able to draw whatever extra you need from your power company. And on other days you will use less electricity than the average, and on those days you will be able to sell back any extra that you produce to the power company. It will all even out in the end, and usually in your favor – depending on your power company, you’ll be able to sell your extra electricity to the power company for more than you are paying for the little bit you need from them on cloudy days or days when your energy use is a bit higher than average.
How Much Will Home Solar Power Cost
The next step is to figure out if you can lower this number. Home solar projects are still pretty expensive, so the more you can lower your daily needs, the less you need to invest in supplying that power. Before you start shelling out dollars for solar panels, maybe it’s the right time to upgrade to a more energy efficient refrigerator, dish washer, or washer and drier. Maybe it’s time to commit to hang drying your clothes. Make sure your computer, television, and gaming systems are all on power strips that you turn off when you’re not using them to reduce the amount of phantom load your electronics are drawing. Upgrade your lightbulbs to LEDs. Before you spend $10k+ on solar panels, spend a couple months committing to lowering your energy use, and then recalculate your average daily electricity use.
A good rule of thumb right now for how much a home solar power project is going to cost you is to multiply your average daily electricity use by 1000. So if your home uses 22 Kwh of electricity per day, the cost of a project big enough to cover your entire energy needs would be about $22,000.
Before you get bug eyed at the cost of a home photovoltaic project, keep in mind that there are currently lots of opportunities for energy rebates. The federal government will give you 30% of the cost of the project in rolling tax breaks. (Rolling means that if you don’t use the whole 30% the first year, you can take the remainder the following years until you reach the full 30%.) Many power companies are also offering rebates for home solar projects right now as well. Mr. Passi gave us some examples of projects that he worked on in the past couple years, and many times the after rebate costs were around 60% of the total cost of the project.
Also, keep in mind that solar panels take up quite a bit of space. You likely won’t have enough room on your roof (especially in a city or suburb situation) to even install enough solar to cover the entirety of your daily use. When you look at how much solar power you can actually install on your house, the scope of your home solar power project may drop significantly. And even if you’re only supplying some of your home electricity needs, on sunny summer days, you will likely still produce quite a bit of extra electricity to sell back to the grid.
I have plenty more to share on this topic, but I think this is a good start for today. In the future I’ll get into more about the components you need for a home solar power project, and use our house as an example for figuring out how much electricity you need to produce and the costs of completing that project.
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