- Renewable & Alternative Energy
The Grid-Tie Version of a Solar Power System
I am not an electrical engineer by any stretch of the imagination. This article doesn't have any actual instructions on how to install a grid-tied solar electric system. It's just an introduction to the concept, as it's a variation on solar power that not everyone knows about.
If you're a fan of clean, renewable energy, you may have thought about going solar. I know I certainly have. But it's a complicated and expensive undertaking, which has put it beyond my reach. Well, I've been reading about grid-tie systems that might be the answer to my concerns.
One of the most expensive components of a solar system is the battery, or more accurately the collection of batteries. They're costly and do take up a fair bit of space. Depending on the kind of batteries you choose, there are venting concerns, maintenance and eventual replacement to deal with. Many people would say that the battery element of a solar power system is the biggest drawback.
A grid-tie system eliminates the entire battery bank, which creates a less expensive system and a less-complex one as well. The basic idea is that you have your regular solar panels up on your roof (or mounted on a rack, or wherever), generating electricity when the sun is out. But instead of that electricity being stored in your bank of batteries, it's run back through your electric meter and back into the 'grid'. You're basically selling electricity back to the system. This runs your meter backwards, and will earn you a credit on your electric bill.
A setup like this may be simpler, but does require that you be connected to the grid in the first place, meaning it isn't suitable for remote homes. It also won't give you any independence from the grid during power outages. If the power goes out, your solar panels aren't going to keep your lights on. That said, you CAN combine a grid-tie system with a standard battery bank, but you lose the "battery-free" benefits of such an arrangement.
Before setting up a grid-tie system, contact your electricity provider to ensure this is allowed. Not all meters work the same way, and you may be required to replace your meter. A quick check of my own provider's website (in Ontario, Hydro One) showed that this is allowed in my area and there are details and applications on the website. When a power company buys at the same rate it sells electricity, it is called net-metering.
Books on Home Solar Power
According to Jeff Yago, well-known solar power expert, "There are currently 35 states that allow utility interconnection or net-metering. Although the utilities that do allow interconnection have different rate structures and billing arrangements, most will allow a monthly carry-forward credit balance, which means those summer months when you generate more power than you use will offset purchased electrical power you used later during the winter months."
Obviously, this is just a simple description of the grid-tie system. If this sounds like something that would suit your own energy situation, I suggest doing more research on the electrical and wiring details, and getting a licensed contractor to give you a hand.