Pumping power onto the grid from your basement

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The $11,000 GridPoint Connect, a separate unit, is sold more on the basis of the economic benefit, Lewis said. It acts as a turnkey system, with an inverter and either 7 kilowatt-hours or 10 kilowatt-hours of storage, to accompany a solar electric system. And its data-collecting tools help consumers shave money off their bills.

"The computers in these boxes are making decisions with regards to energy based on the value of energy at that point in time and the historical consumption of that residence," Lewis said, adding that part of the company's management team has a background in software and communications.

Electricity tariffs that change over the course of the day to reflect fluctuations in demand are still not commonplace for U.S. consumers. However, the Energy Policy Act of 2005 (click for PDF) calls on state utility regulatory bodies to explore "time-based metering and communications" next year, which would allow customers to participate in "time-based pricing rate schedules and other demand response programs."

Another company that is trying to capitalize on "peak shaving" or "peak shifting" is Ice Energy, which makes an air-conditioner add-on that freezes water in the evening to cool the refrigerant, rather than run the AC during heat of the day.

Ice Energy sells its units directly to businesses but is also investigating ties with utilities including those in California that are struggling with the costs associated with meeting peak demand.

Extremely high summer temperatures that tax the grid, such as those happening this summer in the U.S., are happening more frequently, according to Ice Energy CEO Frank Ramirez.

"Utilities used to plan for what they call one in 10 (extremely high temperature) events. Now they are finding they are becoming one in three or one in four events," he said.

"The occurrence of sustained high temperatures is wreaking havoc on the ability to maintain the integrity of the grid," Ramirez said.