Foundation, based in Menlo Park, Calif., reflects this in investments such as Sentient Energy Inc., a smart-grid monitoring company that allows utilities to remotely find power outages, and Silver Spring Networks , which provides utilities a wireless network for advanced metering and remote service connection.

Another holding, EnerNOC , a demand-response business with technology to turn off noncritical power loads during peak periods, went public in 2007.

EMeter , a one-time Foundation investment, was recently acquired by Siemens Industry.

To be sure, investors have not abandoned costlier technologies with longer-term horizons, but many — put off, in part, by last year’s bankruptcy and shutdown of solar power firm Solyndra — now favor smaller infusions in businesses with a quicker potential payoff.

Rob Day, partner in Boston-based Black Coral Capital, says his cleantech investment firm maintains some solar holdings, but he sees a shift from an emphasis on those types of plays to more “intelligence-driven, software-driven, web-driven businesses.” These technologies can be used to improve existing businesses, he says.

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