But Richard Smith, head of energy strategy for National Grid, told BBC News that other sorts of storage would be increasingly important in coming decades and should be incentivised to commercial scale by government.

BBC: Liquid air 'offers energy storage hope'

For now, Stanway is buying just for Wal-Mart's Texas store needs while eyeing the potential for expanding the strategy to stores in power grid regions like Louisiana, California and, naturally, Arkansas.

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In particular, the BPA has yet to offer a viable alternative to the rolling wind outages strategy, which would have ensured the grid complied with federally mandated reliability standards and protected salmon populations from the anticipated flood of freshwater.

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The Defense Science Board Task Force report on DoD Energy Strategy emphasized that fuel cells present an enormously compelling strategy for avoiding the risks associated with over-reliance on the national electrical grid.

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This strategy also lends itself to distributed energy generation on local microgrids which can be smartly connected to the existing nation grid.

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