Only a few days after the United States extended nearly $18 billion worth of renewable-energy tax credits, trade delegations from Spain and Germany have arrived to seek investment and technology deals in the country.

In separately organized visits, renewable-energy companies, politicians and scientists from Spain and Germany are visiting California, Nevada and Oregon this week, reflecting the growing importance of the United States in the renewable-energy market.

With far more aggressive policies, Germany and Spain are the top two solar-energy-consuming countries in the world. The countries' feed-in tariffs – which pay renewable-electricity generators a set price higher than that of conventional electricity – have enriched not only domestic solar-equipment makers and installers, but also those from the United States and Asia (see Spain Approve 500MW for Solar and Solar Prices Set for Germany).

But many companies worldwide see the United States as one of the next potentially largest markets for solar and other renewables (see U.S. Solar Could Surpass German Market by 2011).

While the trips were likely organized before the U.S. Congress and President Bush approved incentives for solar, wind, geothermal, biomass and other types of developments, the multiyear program no doubt makes the country even more alluring to potential investment (see Lawmakers Approve Energy Tax Credits, Bailout).

A slew of states and local governments also are offering incentives for businesses and residents to install solar power panels (see California Cities to Offer Solar Loan Program and Massachusetts Passes Sweeping Energy Bill).

Spanish solar and wind companies already have committed billions to produce power for the U.S. market. Wind-energy giant Iberdrola recently won a fierce permitting battle to buy a utility in the northeastern United States for $8.3 billion (see Iberdrola Says Yes to Energy East Deal). Abengoa Solar, which had previously said it would halt its U.S. plans if the federal tax credits weren't extended, is developing a 280-megawatt solar-power plant in Arizona.

The Spanish delegation, which is visiting California, includes representatives from the country's largest trade association, the Spanish Confederation of Employers and Industry, and from solar companies already doing business in the United States, such as Abengoa Solar, Siliken Renewable Energy and Acciona Energia.

The Spanish delegation picked California because the state has enacted some of the strongest renewable-energy policies and most generous incentives in the country. California utilities are required to buy 20 percent of their electricity from renewable sources by 2010, and the state intends to further limit greenhouse-gas emissions by setting up a carbon cap-and-trade program (see California Offers Plan to Clear the Air).

The delegation plans to meet with California regulators, utilities, legislators and businesses such as San Diego-based Sempra Energy, whose subsidiaries include San Diego Gas & Electric and Southern California Gas Co.

Some of the delegation members also plan to attend the Solar Power International conference in San Diego, Calif., next week, said Janice Cooper, senior vice president of Solutions International, a consulting firm that organized the visit.

Meanwhile, the German delegation plans to meet with staff at the Nevada Commission on Economic Development and the researchers at the Desert Research Institute, which is hosting a symposium on Tuesday for the occasion.

The German delegation includes Saxony state officials, scientists and economists, who will meet with researchers at the Desert Research Institute to discuss geothermal and wind power, fuel cells and wastewater treatment, according to institute spokesman Greg Bortolin. AST Applied System Technics, geoEnergie Konzept and Busse are among the German companies participating in the trip.

The delegation is particularly interested in geothermal energy and wastewater-treatment technologies and plans to visit Ormat Technologies, based in Reno, Nev.

The Germans also plan to visit California and Oregon.