What happened

Shares of solar energy stocks had another great day on Tuesday, climbing on the back of a rising market and some good news for the industry. Gains were widespread, but there were a few companies that led the industry today.

SunPower (SPWR -3.09%) was up as much as 18.2%, JinkoSolar Holding (JKS -0.34%) was up 9.9%, and Enphase Energy (ENPH 0.62%) jumped 7%, while developer Brookfield Renewable Partners (BEP -1.66%) rose 5% at its peak. The stocks were up 17%, 9.5%, 5.2%, and 4.8% respectively as of 3 p.m. EDT.

Solar panels at sunset with a single wind turbine in the background

Image source: Getty Images.

So what

The first company-specific news was about SunPower, which had its price target raised from $22 to $35 per share by Piper Sandler analyst Kashy Harrison. The company's rating remains overweight, and the analyst thinks President-elect Joe Biden's energy plan could continue to fuel solar-energy stocks in a long-term trend.

Treasury secretary nominee Janet Yellen was also before Congress today, urging lawmakers to "act big" on an economic relief package. Not only are those comments on the stimulus being cheered, but they seem to indicate that Yellen will push to keep interest rates extremely low for the foreseeable future, which would help keep financing for solar energy projects low.

A general trend over the last six months has been rising prices for solar energy stocks, on hope that subsidies and stimulus payments will increase under a Biden administration, and that regulatory policy will be more favorable. That's the same trend we see today -- except this time, the policies being discussed are a bit more concrete.

Now what

On days like today, the market's speculative streak has taken over the solar industry and shares are rising without much in the way of concrete news. There aren't earnings reports or big contract signings driving revenue growth and profitability. But sometimes big gains come on days when tailwinds carry stocks higher.

What I would take more interest in is the policies a Biden administration could put into place to help the solar industry. Yellen will be one of those people helping make policy, but there are a lot more questions to be answered as to how regulators will adjust policies to favor renewable energy -- or whether they'll push for more subsidies. Right now, the market thinks the solar industry will be one of the biggest winners of the Biden presidency. Given the push for spending from the highest levels of government, it's hard to argue that won't be the case.