Solar works great but much of the energy produced is lost during the peak demand time of day. Solar panels on your house are busy from 9:00 AM to 3:00 PM pumping out free clean electricity. Utility companies are straining at 3 – 7 to provide enough community power without having to go outside their network and purchase power at a loss. Well now help is on the way for homes and cars using computer battery technology.
There are huge global solar energy corporations and small companies that are working hard to change the way home solar energy is produced and used by providing affordable home power to use during off-peak hours.
Sanyo is one of the few global solar companies to provide everything needed in the energy loop: Energy generation with solar, energy storage with large capacity lithium-ion battery, energy-efficient air conditioners and commercial refrigeration and energy controller to maximize the efficiency.
This is core of SANYO SES solar battery system. High capacity Lithium-Ion battery system with a controller to maximize the battery life. Lithium ion battery is a long life, reliable and safe solution for energy storage, and standard models for renewable energy storage and mobile application will become available later this year for homes. Since SANYO has long-term experience with temperature management of lap-top PC batteries, and is able to provide safety and reliability with in a home battery system.
Sanyo is not the only company working on this solar battery technology. At the other end of the corporation scale is a small but committed company in the Midwest is also trying to change the way energy is produced and consumed. Silent Power has developed an energy-storing system that its leaders say makes renewable sources such as solar and wind more efficient and practical at the residential level.
The company aims to overcome one of the biggest challenges with renewable energy: how to save it for when demand is the highest. Solar energy peaks around midday when the sun is highest. Wind actually produces the most power at night. But the time when people use the most electricity is roughly 4-7 p.m.
“The dilemma is most of this renewable solar and wind energy is being produced when it’s not needed most,” said John Frederick, vice president of sales and marketing for Silent Power. Today, most utility companies can’t store energy. But Silent Power is working hard to change that by offering a way for individual homeowners to bank electricity for times when they or the utility company need it.
The company is partnering with utilities around the nation on demonstration projects. Solar battery storage could play a role in smoothing out the variability of solar energy and making it more effective, said Kevin Lynn, systems integration lead in the U.S. Department of Energy’s solar energy technologies program.
“We have a real interest in seeing higher and higher penetrations in solar going on the grid and supplying higher and higher amounts of energy for the nation as a whole,” Lynn said. Silent Power was founded seven years ago to develop fuel cell technology. Its focus changed to solar battery storage about 2 1/2 years ago, Frederick said.
The company is funded by local investors and has grown to about 20 employees despite the recession. An expansion is planned for later this year. The storage device, called on-demand, converts electricity produced by solar panels, a wind turbine or other source from direct to alternating current. It stores electricity in lead acid or lithium-ion batteries manufactured elsewhere. A utility company can communicate with the system and decide when the stored electricity should be released during times of highest use.
That’s significant, Frederick said, because utilities build everything power plants, transmission lines big enough to handle that peak demand. If the peak can be reduced utilities wouldn’t need to invest so much in generation and transmission. Additionally, there is a tremendous amount of electricity that is lost in the fulfillment process transmitting electricity over those high power lines.
“Over the long run, costs go up to meet those peak demand times,” said Sonja Bogart, vice president of customer service, sales and marketing for the Wright-Hennepin Cooperative Electric Association, one of Silent Power investors.
This spring, Wright-Hennepin plans to install one of the solar battery devices at its headquarters in Rockford, where it already has solar panels and a wind turbine. Utilities see the technology as promising to solve future demand issues and to bring renewable energy into the mainstream, Bogart said.
“All of the sudden you can use renewables when you need them and not just when they’re generating,” she said. As part of a pilot project, Wright-Hennepin plans to seek 10 homes to install the devices this summer, Bogart said. Customers can use the device as a backup source of electricity during a power failure. Over the long run, it would lower energy bills after a payback period, Bogart said.
One lingering question is whether the cost of storage is too expensive for most homeowners. The units cost about $13,000 each, Frederick said. The company hopes to bring that price down to $10,000 by producing larger volumes. The federal government offers a 30 percent tax credit for solar projects. Silent Power hopes utilities will offer homeowners a rebate if they install one of the units. That would bring the cost down to a reasonable level for a homeowner who wants to have a backup source of electricity, Frederick said.
Right now, most utility customers in Minnesota are insulated from the true cost of electricity. Aside from saver programs that turn off air conditioners and furnaces during peak times, most customers pay the same rate for electricity no matter what time of the day they use it.
But some states like California are starting to adopt time-of-use rates. Customers pay more for electricity used during peak times. Frederick believes those rates eventually will be adopted everywhere as part of the nation’s evolution to a smart grid. At some point, they’re going to start passing that on so you as a consumer can make choices about when you use electricity,” he said.
Dave Gruenes, district manager of Stearns Electric Association, called Silent Power’s solar battery technology promising. But he isn’t sure the market is ready. Gruenes noted that Silent Power is concentrating sales on the West Coast, where electricity prices are 2 1/2 times higher than in Minnesota. The company is partnering with the Sacramento Municipal Utility District on a 15-home pilot solar battery project.
Gruenes isn’t sure utilities will see a big enough financial benefit to make it worthwhile offering customers a rebate to install the storage devices. About 10 of the roughly 25,000 Stearns Electric members have solar panels. In the next several years if the price of solar comes down, the idea might become more attractive, Gruenes said.
“I still think we’re a ways off here,” he said. One goal of the Sacramento project is to determine the value of storing energy to both the utility and the customer, Lynn said. Cost is still an obstacle, but if it can be reduced, storage could be a big part of the solution to energy problems, he said.