Consumer and environmental advocates say aggregation is a way to quickly create a large demand for green power--and, potentially, to shift the nation toward more renewable energy.

But experts say that individuals alone buying green power packages will do little to raise the minuscule percentage of energy that comes from truly renewable sources. Energy economist Eugene Coyle explains that only about a third of the total electricity consumption in the United States comes from residential use. Assuming that only 10 percent of residential consumers sign up for a "green power" package, and that it offers only 50 percent renewable energy (as is typical of most such packages), only 1 percent of available energy would come from green sources.

"Through aggregation, people could put money into buying or building a green power plant," says Coyle. "Or they can contract with existing green power facilities to get as much green power as they can, or do both."

"What we''re talking about is democratic control of our resources," says Julia Peters of the Oakland-based American Local Power Project. "We''re talking about being green citizens rather than merely green consumers."

A 1995 poll conducted by Salem Electric in Oregon suggested that people are more willing to pay extra for green power if the cost is spread among a large group of consumers.

"Aggregation is a way to make green power more affordable to more people," Coyle said.

Without aggregation, consumer advocates fear that green power will become a luxury item: A few well-off consumers will opt to pay more to feel good, but the overall energy mix in the nation won''t change.

"If you''re buying a green product right now, you''re buying already existing green power that has already been created because of state regulations and is now being sold to you as premium power," says consumer advocate Paul Fenn of the American Local Power Project. "But by getting together a large group of consumers, you could establish a large enough demand to quickly force new green power into the system."

According to Rich Ferguson of the Center for Energy Efficiency and Renewable Technology (CEERT) in Sacramento, no new green facilities have been built in California since the early 1990s.

The problem with green power marketing right now is that, for the most part, only the largest corporations with the deepest pockets have entered the market (see "Plugging In," page 15.) Most of the "green" products offered right now are from affiliates of corporations that are, for the most part, big polluters.

"A choice between the monopoly and the monopoly''s corporate sibling is not much of a choice," Theresa Mueller, an analyst with the San Francisco consumer group The Utility Reform Network (TURN), said in a recent organization newsletter.

Vermont-based Green Mountain Energy, whose parent company has a relationship with Hydro-Quebec, is offering a deal in which the company promises that if enough people sign up, it will build a wind-powered facility. Enron has pledged to build a wind plant as well.

But at the same time, the money these companies make can also go into less environmentally sound ventures. Mission Energy, owned by Edison International, is part of a venture to build coal-burning plants in Australia, India and Indonesia.

For consumers, this presents a dilemma: If consumers refuse to buy green power packages from companies that also pollute, will those companies have any incentive to shift to renewable resources?

"I hate to send my money to the dirty companies, so I sympathize," says CEERT''s Ferguson. "But the flip side of that argument is that the bad guys are going to continue to do bad things if they don''t see a demand for green power."

The San Francisco-based Center for Resource Solutions (CRS) is trying to encourage accountability on the part of marketers. In exchange for paying CRS to get a Green-E label, which requires the product to be at least 50 percent renewable, utilities are subject to a CRS review of the company''s contracting record within six months to make sure it is buying the green power the company has promised consumers.

But there are other problems with the current green marketing beyond accountability.

For example, Green Mountain Energy has contracted to get its green power from Oregon-based PacifiCorp, which has some renewable sources of energy but has mostly coal plants and some hydropower. Nancy Rader, an independent power consultant and wind power advocate, pointed out that ratepayers in other states likely have paid for PacifiCorp''s generating facilities already. Doesn''t that suggest PacifiCorp will be subsidized more than once by ratepayers?

And, Coyle points out, if PacifiCorp sends what renewables it has to Green Mountain, won''t the company just send its dirty power elsewhere?