What happened Stock markets saw a bit of optimism last week, with the S&P 500 putting together a modest three-day rally. But after Tuesday's downturn, and today's even deeper downturn, it appears we'll have no such luck this week. Certainly not for solar stocks. Tuesday, shares of solar panel maker SunPower (NASDAQ: SPWR) and solar installer Vivint Solar (NYSE: VSLR) suffered share price declines, while solar thin-film specialist First Solar (NASDAQ: FSLR) fell flat. Today, all three stocks are down sharply, with SunPower falling 5.9% as of 12:55 p.m. EDT, First Solar down 7.2%, and Vivint off 9.2%. An aerial view of a solar farm. Image source: Getty Images. So what There was no bad news directly affecting any of these three companies today. To the contrary, there's actually some good news: Today's edition of The Wall Street Journal notes that "investors hungry for low-risk, stable-yield opportunities are looking to wind and solar farms, which could give renewable energy projects a financial boost in coming months and years." This logically bodes well for solar stocks as well. Granted, the middle of a global pandemic that's bringing down the price of oil and making alternative energy sources less price-competitive might seem like a strange time to get excited about solar projects. But as the Journal points out, a similar dynamic was evident immediately following the 2008 financial crisis, "when investors seized on [solar and wind] projects as safe-harbor investments with yields in the mid-single-digit percentages." Now what Probably, investors today are reacting more broadly to news about the coronavirus, which hit 887,000 cases and more than 44,000 deaths globally today. This is taking down a lot of stocks in Wednesday afternoon trading, and it's no surprise to see solar shares among them. Moreover, while the Journal sees reasons for optimism about the solar industry, SunPower, Vivint, and First Solar do not currently generate any positive free cash flow whatsoever. If cash is coming in the form of new energy-farm projects in the future, that's well and good. In the meantime, though, these companies still need cash to survive today. Until they prove that they can generate it, I expect their shares to remain vulnerable. 10 stocks we like better than First SolarWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and First Solar wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of March 18, 2020 Rich Smith has no position in any of the stocks mentioned. The Motley Fool recommends First Solar. The Motley Fool has a disclosure policy.Source