Alternative energy analysts are warning stock valuations may be too rich after surges from the U.S. election and hopes a Democrat-controlled Congress will put forward industry-friendly legislation.

With Democrats securing control of the Senate this week, the WilderHill Clean Energy Index has gained another 19% to start the year following a 203% increase in 2020. But investors may be overzealous.

“Now that the proverbial champagne has been poured to celebrate the stellar 2020, it is our duty to sound a note of caution,” said Raymond James analyst Pavel Molchanov in a note to clients.

The Houston, Texas-based analyst downgraded five alternative energy and clean technology stocks Friday, urging investors to lock in profits while still looking for new opportunities.

The slim majority Democrats won may help President-elect Joe Biden fulfill his pledge to promote the use of electric vehicles and clean energy. But sweeping legislation such as the Green New Deal to combat climate change are still on ice.

Included in Molchanov’s downgrades was solar power manufacturer Enphase Energy Inc., which he cut to a sell-equivalent rating following the stock’s record 568% gain in the past year.

With investor sentiment on clean tech “as high as it has ever been,” valuations are at elevated levels, and many at records, Molchanov said.

Earlier this week Susquehanna also downgraded Enphase and SolarEdge Technologies Inc., citing stretched stock values.

“Although we think the outlook for the solar sector remains robust, most of the external catalysts for the sector are being priced in or have already come to fruition,” analyst Biju Perincheril wrote.

Goldman Sachs maintained a positive stance for solar in 2021, though it was more selective on stock picks. Analyst Brian Lee said he prefers residential solar-exposed companies, and upgraded Enphase to a buy, while downgrading First Solar Inc. to a sell.

Elsewhere, EV-exposed stocks continue to soar Friday, with Tesla Inc. extending its record win streak, while Plug Power Inc. also gained after SK Group’s $1.5 billion investment in the fuel-cell maker.

This article was provided by Bloomberg News.