Solar power, wind and biotech made record money last year and promise excellent results in the future, but first, companies must survive the world financial crisis, a report said on Tuesday.

The CleanEdge report said global revenues in the three premier clean technologies grew to $115.9 billion in 2008 from $75.8 billion. But don't expect a repeat performance this year.

We see growth long-term, but in 2009 we'll either hold steady or see a decrease in revenue. 2009 is the year to get through, said Ron Pernick, one of three authors of Clean Energy Trends 2009.

The number of clean-tech jobs will grow to 2.6 million in 2018 from 600,000 last year, the report says.

For now, the U.S. government's stimulus program will help, with more than $70 billion in direct spending and tax credits. Of that, $4.5 billion will help upgrade meters and two-way communication for smart grids aimed at cutting peak usage and encouraging consumers to manage power loads.

Companies that make smart grid equipment have been backed by venture capitalists, who spent $3.35 billion on clean tech last year.

Solar and wind power require upgraded power grids to wheel the electricity from sparsely populated areas to consumers, and the U.S. stimulus package has $17 billion for that. Lines are being constructed in Texas, Michigan, the Dakotas and Iowa.

In Europe, Ireland's Imera Power is spending $5.6 billion to link offshore wind farms to markets in Britain, Ireland, France, Belgium and Germany.

Sometimes the wind does not blow and the sun does not shine, so storage is necessary. A high-capacity 1 megawatt sodium-sulfur battery made by Japan's NGK Insulators is being tested at a wind farm in western Minnesota.

A second solution is to store heat instead of electricity. SkyFuel, SolarReserve, Abengoa Solar and Andasol are building molten salt plants to store solar heat for use in steam turbines, seeking to cash in on the physics advantage that it's easier to store heat than electrons, the report says.

Alternative energy can be strategic. An impetus for European initiatives has been the uncertainty over gas supplies from Russia because of political disputes, the report says.

Wind power, already popular in Germany and Denmark, doubled in Turkey last year and Poland was up 71 percent. Wind power is under development in Belarus, Bulgaria, Spain, Poland, Romania, Hungary and Estonia. France, which relies heavily on nuclear power, added 950 megawatts of wind power last year.