Batteries not included
Almost a hundred million dollars of new investment in battery technology has been announced in the few days: first, Boston Power announced that it had received $55M in a fourth round of funding for their Sonata lithium-ion battery. The Sonata is advertised to have a very long lifetime, a quick charging cycle and makes a variety of environmentally friendly claims.
Next, GM announced that it will spend $30M on an assembly plant for the batteries for their up-and-coming Volt electric vehicle. This followed an announcement that Tesla would begin to manufacture batteries for other electric vehicles as well as their own Tesla Roadster.
These announcements reinforce just how important energy storage will be with the advent of new renewable energy technology.
Drivers, homeowners and businesses need power all the time. But America’s wind farms, solar arrays and electric cars can’t simply make electricity around the clock. Because renewables are a small enough piece of the US energy pie (7% in 2006, less than half a percent if you exclude hydro and biomass), the rest of the grid buffers periods of up and down time.
But as we approach the levels of renewable electricity generation that many environmentalists hope for, we will have to solve the issue of delivering constant supply from intermittent generation. Batteries are a great solution for the likes of electric and hybrid cars but how might you store energy from a large solar array or a massive wind farm?
Fortunately some very smart people are thinking about that very question. One interesting possibility that has recently been getting some press is compressed air energy storage technology. In this approach wind energy is used during periods where energy is readily available and the wind is blowing (at night) to compress air and force it underground. During times of peak demand the compressed air is then used to generate electricity for the grid.
There has also been interesting work done on pumped storage, where off peak electricity is used to pump water up to a storage reservoir and then during peak hours its flow back downhill is used to generate hydroelectricity.
It has been great to see so much investment into new, renewable energy generation technologies, but all this battery talk should serve as a strong reminder of just how far we have to go before we can fully implement a renewable energy system for the US. If you’ve heard of any other large-scale chemical or physical energy storage technologies leave a comment, we think all of this stuff is pretty neat.