One of the advantages of flow batteries is they can be charged and recharged nearly an unlimited number of times without degradation, according to Watkins.
While Watkins admits to a higher initial cost for vanadium flow batteries, he said such comparisons fail to account for other factors that impact overall system cost. Watkins pointed to the levelized cost of energy (LCOE), which factors in the system's useful life, operating and maintenance costs, round-trip power efficiency and residual value.
Because flow batteries, like the vanadium-flow batteries Imergy makes, are very long-lived, deliver more cycles and can be used for multiple applications, "the overall cost structure is substantially below the pricing for an equivalent capability delivered by lithium batteries," Watkins claimed.
One problem with flow batteries is that they're enormous. In order to power a house, you'd need a flow battery about half the size of your garage, Frankel said.
In the end, the distributed energy market will probably use a range of different battery technologies, Frankel added.
In the way of Musk's renewable energy utopia are governments that have been doing business with fossil fuel suppliers for more than 100 years, and developing nations that need an established energy source.
For example, China's government is dealing with massive consumer growth, which for the immediate future can only be satiated by established energy technologies such as fossil fuels. While the government recognizes the need to reduce pollution, and has established some policies such as driving restrictions to do that, it's also under the gun to enable economic expansion in a nation with 1.2 billion people.
"When China looks across the globe to the U.S., they see the west as having used fossil fuels for 140 years and they've been expanding its use for the last 20 years. So they're going to say mind your own business," said Brian Buchwald, CEO of Chinese market data firm Bomoda. "They're not concerned with the impact on the rest of globe."
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