Wall Street Journal this morning (2-3-2015) had an interesting article on the latest threat to the US Power grid - Energy-Conserving Americans.
Since 2004 residential electricity prices have jumped 39%. Yet, retail sales to homes and businesses are still less than they were in 2007.
Customers are embracing "energy saving gizmos" and solar panels pushing down the demand for grid power.
"NRG Energy is tinkering with prototype of stove-sized machines that make electricity from natural gas" ie Stirling engines. "Something the company says is likely to appeal to the roughly 50% of US homes served by gas"
The full article can be found here.