According to this article in the WSJ, the market for batteries is potentially huge due to the push to use alternative energy and avoid fossil fuels. Lux Research Inc., which tracks emerging technologies, reports that the battery market could be as $50 billion if only 10% of wind-power plants installed them. It predicts, however, that the actual market will be much smaller because of the long planning cycles and risk-aversion of utilities. This isn't surprising given how expensive the batteries can be - e.g., on the order of $10 million for a relatively small one.
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