Kauai to Build a Powerwall of Batteries that Use Solar Energy

We get a lot of questions about solar energy, but one of the most common is this: How can I get solar energy in the evening?

That’s a really valid question, and the simple answer is “there’s no way.” Solar power comes from the sun, which appears only during the day. However, despite the absence of the sun at night, it shouldn’t stop you from enjoying the benefits of solar energy during the evening. In this light, let us rephrase the question:

“How can I use solar energy in the evening?”

The short answer: by using batteries. During the day, the energy from the sun is converted to electricity and sent directly to the power grid. Some of this energy, however, may be directed to powerful rechargeable batteries that will power up your home or building even when the sun is down. This is the vision of Powerwall, a home solution by Tesla Motors for storing solar energy.

With this solution in mind, the island of Kauai in Hawaii recently coordinated with Powerwall to put up a huge Powerwall assembly that can supply power to a fifth of its electricity requirement for an unspecified number of hours. According to a news release, the island will use the services of SolarCity for the “first utility-scale solar array and battery storage system designed to supply power to the grid in the evening, when demand is highest.”

The proposed solar system will be built on an old sugar plantation near a power station in the island, and will be able to generate 17 MW of power. An array of lithium ion batteries will be placed within the lot, covering about two-thirds of an acre.

Hawaii, just like California, is now relying on solar energy to power electricity-dependent systems and homes. Through this new initiative with the Powerwall, Kauai is gradually shifting gears from fossil-fuel power to the sun’s natural energy.

[Photo courtesy of Wally Gobetz on Flickr]