Green power, from PacifiCorp, will be the most expensive of four choices offered to 6000 customers in Clark County, Washington state, from March 1 in a green package of electricity including wind -- but it will be the most benign environmentally. It will cost $0.057/kWh, or 30% more than the ordinary mix. The Powerful Choices test campaign was authorised by county regulators in January. Customers can have different proportions of each choice, in 25% increments, but are locked into their overall package for one year. Included in the test run are 200 commercial customersr. The experiment is to give Clark County a head start when deregulation becomes mandatory, say officials. "It used to be that regulators told us what power to buy," says Gary Saleba, who works on the programme. "The whole paradigm has changed under customer choice and direct access. Now the customers tell us what they want."