Most people are at work during peak sun when solar panels are making the most electricity. If you wake up with the sun, your solar panels can heat the hot water for your shower, toast your bread, and run your wifi when you catch up on email. Your solar panels will be powering your refrigerator and air conditioner while you’re at work along with anything else electrical you run while you’re away: security systems, computer updates, electric fences, etc. When you come home in the evening, you have a short time to do laundry and cook dinner before the sun goes down. By the time your lights are on, your solar panels are done for the day. What happens to all that excess electricity that’s made while you’re gone? There are two answers to that question.
Most people choose net metering. When your solar panels make electricity that you don’t use, the power is sent from your home through the grid to wherever it’s needed. The next month, the electric company pays you for the electricity your solar panels created. The electric company gets to send the power to the businesses and schools that need it right at the time your panels make it. They pay you for keeping the lights on at the school down the road during the day which offsets the costs when you turn on your own lights after dark.
Energy storage is a different solution. Energy storage is Solar Speak for using batteries with your solar array to capture the power made by solar panels for times when no energy is being made. Instead of selling your power to the electric company during the day and buying power from them at night, you would store your excess power during the day and use it at night. You’d still be running your toaster in the morning from your solar panels, but at night your lights would be running off the batteries that charged while your were at work. Sounds great, right? There’s a catch.
It can double the cost of a solar installation.
Whew! That’s a doozy of a catch!
There are a number of factors that mildly increase the cost of an energy storage system. For example, the system complexity increases design and installation time. However, the main cost is in the batteries. The batteries are expensive right now, like any cutting edge technology. Remember computers used to cost what a house costs today. As the market grows for solar energy storage, the cost of the batteries will fall. For now, they make the whole idea cost-prohibitive. We predict that the costs of energy storage batteries will drop as the technology matures. When that happens, PlugPV will review our current policy which is:
Energy storage is not worth the price.