Using renewable energy can be tricky. For example, when the wind blows and people need power, life is pretty simple for wind turbine operators. But what happens when the wind blows at off-peak times? Can that energy be stored? As most of us already know, the answer is “yes, but we’re still working on the best way to do it.”
On Monday we shared with you MIT’s advances in energy storage: Cambridge crude. Today we’re sharing another promising method: compressed air storage.
General Compression, based in Newton, MA (do we see a trend here?), was founded in 2006 with a goal to make renewable energy, such as wind power, less intermittent and more “dispatchable.” In other words, they wanted to develop a way to use energy generated by wind turbines even when the wind wasn’t blowing. The obvious benefits of their goals would be to utilize more of the wind power available in the US, and to therefore put more renewable energy on the grid. If electricity generated by wind power could be called upon even in times of low to no wind, the resource could start to become useful for more than peak-load generation, and might just contribute to base load needs, which we all know are rising despite energy efficiency efforts.
What makes wind energy “dispatchable,” you might ask. The answer is some kind of storage device that allows the energy to be drawn on demand. The key questions when choosing a storage method are: what will be used to hold the energy, and how much energy will be lost in the process? Obviously batteries are often remembered as great energy storage devices. One reason lithium ion batteries are appealing is that they have a high power density compared to other batteries. But there are other ways to store energy without batteries. Compressed air is one such way.
General Dynamics’ technology uses the power generated by turbines to pump air into underground geologic formations. Energy is stored as compressed air, and then released when wind resources decline. The released air drives turbines in the power plant on the surface, and thus wind energy is able to provide electricity even when the wind doesn’t blow.
We like the technology because it’s smart, simple, and able to be implemented today. Oh, and we also like it because it’s green.