Many homes could generate all their own power by wind or solar energy and sell the surplus, the government has said.
Wind and solar power can aid self-sufficiency, ministers say
Energy minister Malcolm Wicks launched a consultation paper on how to boost "micro-generation" by homes, businesses and public buildings.
The government is seeking ways to solve high costs. A solar panel system could take 120 years to save what it cost to install, government figures say.
But renewable power groups have called for clearer government policy targets.
"Power generation has traditionally been about giant stations supplying whole cities, but the future may show that small is big," Mr Wicks said at the conference of the Renewable Power Association (RPA).
But RPA chief executive Philip Wolfe said later: "The gap between the government's intention to develop our renewable energy sources and the policy measures that are needed is still too big."
A Department of Trade and Industry (DTI) spokesman said the cost of renewable energy devices had been recognised by the government.
It wanted to "get the industry moving forward" so that the cost of individual units fell.
"We don't need a new energy policy, we just need the government to deliver the goals they have already announced," Mr Wolfe said after the conference.
The Micropower Council - comprising practitioners in sustainable small-scale power and heat production - expressed disappointment at a "missed opportunity to inspire confidence in the industry".
The document contained no mention of targets to stimulate investment, said council chief executive Dave Sowden.
He said companies wishing to scale up their production repeatedly complained "how difficult it is to attract investment against such an uncertain energy policy background".
Guy Thompson, director of the charity Green Alliance, said: "The strategy makes some progress but it's disappointing that so few specific policy measures are mentioned.
"Notably, no specific measures are proposed for stimulating uptake and consumer demand for micro-generation - an area where policy support is desperately needed."
Provisions for households to sell their excess energy to public providers already exist - but the process is quite difficult and needs redesign, Russell Marsh of Green Alliance said.
Mr Marsh said other government departments as well as the DTI needed to come on board - particularly the Treasury, responsible for tax incentives, and the Office of the Deputy Prime Minister, which oversees the planning process.