WASHINGTON (AP) _ Electricity being sold as environmentally friendly in California's newly competitive power market ``is largely a hoax on consumers,'' an enviromental-consumer group charged Thursday.

Public Citizen, which was founded by consumer activist Ralph Nader, said that while customers pay an average of $10 extra per month to get so-called ``green electricity'' the purchases do little to enhance the environment.

``The 'green' is going mostly into the pockets of marketers,'' said Joan Claybrook, the organization's president.

The criticism brought a sharp response from California utility officials, as well as some other environmentalists and renewable energy advocates who said Public Citizen's analysis was flawed.

Ralph Cavanagh, an energy specialist at the Natural Resources Defense Council, said demand for renewable energy, indeed, is being spurred by competition and ``green'' marketing.

``The green markets are, in fact, working and working well. ... Public Citizen is completely out of touch,'' said Jan Smutny-Jones, executive director of a coalition of renewable energy producers in California.

Eileen Arbues, senior vice president for marketing at Edison Services, a marketing arm of Pacific Gas & Electric, disputed claims that the premium charged for green power was largely going for marketing. She said most of the added charge goes to buy more expensive renewable energy.

Public Citizen has been a leading critic of California's electricity restructuring effort and has campaigned for passage of a referendum before voters Nov. 3 that would essentially reverse the movement toward competition.

California's law on electricity industry restructuring requires that a percentage of electricity sold come from renewable sources such as wind, solar or geothermal power. As a result utilities and electricity marketers have been selling so-called ``green power,'' which claims that the electricity comes from renewable sources.

But Public Citizen maintained that such marketing in California has had ``no positive impact on the environment.''

``Most marketers (of green power) are merely reselling renewable energy that other consumers are already paying for and that would continue to operate regardless of any resale to green consumers,'' Public Citizen said.

The California marketers are ``taking advantage of people who want to do the right thing,'' said Wenonah Hauter, director of Public Citizen's Critical Mass Energy Project. ``They are deceiving ratepayers into believing the extra dollars they pay for 'green' electricity are actually promoting the greater use of clean, renewable energy sources.''

Instead, the report said most of the additional cost of ``green'' power goes for marketing and advertising, many environmentally beneficial product claims cannot be verified, and false and misleading green product claims are common. In addition, it argued, many of the state's ``green'' electricity marketers are affiliated with larger ``polluting companies and are not advocates of renewable energy policies.''