What happened 

Clean energy stocks have been all over the map on Wednesday with some jumping and others dropping. Speculation is part of the reason stocks are moving so much, but there are some underlying changes in the market over the past few weeks to keep an eye on. 

Blink Charging (BLNK 5.46%) dropped as much as 8.6% in trading on Wednesday and is down 8.2% at 2:30 p.m. ET. Canoo (GOEV 5.88%) was down as much as 5.9% but recovered and is now up 1.5% on the day, while SolarEdge Technologies (SEDG 5.82%) jumped as much as 7.4% and is now up 3.3% on the day. So, why the volatility in an industry that usually moves in one direction? 

So what 

It's odd that electric vehicle (EV) stocks and solar stocks are heading in opposite directions because usually they are impacted by similar forces. But today that's changed, and it may be a sign of what's to come. 

The EV industry is struggling as more companies start to offer discounts to buy electric vehicles. In the past week, we've seen Lucid and Tesla both begin offering discounts to buyers, a sign that demand may not be keeping up with increasing supply. EV maker Canoo is smaller and higher risk than its bigger rivals, so it makes sense the stock would suffer as well. 

Not surprisingly, charging stocks like Blink Charging are falling because they're dependent on EV growth to drive demand. Blink Charging isn't profitable with the amount of demand it has today, so if growth slows the business could be in trouble. 

Solar energy stocks are doing much better in part because the International Energy Agency just revised its projection of installed renewable energy capacity up by 28% from a year ago to over 450 gigawatts by the end of 2027. The agency thinks solar energy capacity will be larger than coal by "early 2025." This is just another validation of the solar industry's growth.

Now what 

The reality is that electric vehicle companies and solar energy companies are similar in the sense that they're manufacturing a product that's beholden to supply-demand dynamics. If supply is higher than demand, profits will go down, and that's what investors are worried about with EV companies right now. 

Solar investors are familiar with this supply-demand dynamic given a decade of fluctuations between the oversupply and undersupply of solar panels. But it looks like demand is going up globally because solar energy is now so cost-effective compared with fossil fuels. 

It seems that the EV market will be under considerable pressure in 2023 as more supply hits the market and consumers start pulling back spending on large items like vehicles. But solar energy has tailwinds, and that's why I continue to be bullish on solar energy stocks.