What happened 

Shares of Clean Energy Fuels (CLNE 5.98%) fell as much as 17% in trading on Wednesday after the company reported fourth-quarter 2022 financial results. Shares are down 12.8% at 2:45 p.m. ET. 

So what 

Management said 54.4 million gallons of renewable natural gas were delivered in the quarter, up 21.2% from a year ago. And revenue increased from $91.9 million to $113.8 million. But the company's non-GAAP (adjusted) net income dropped from $6.4 million to $2 million, or a $0.06-per-share loss.

Analysts were expecting a $0.01-per-share profit from Clean Energy Fuels so results were well short of that. After years of waiting for operating leverage to show up in the business, it's not clear when Clean Energy Fuels will ever generate a consistent profit and in 2023 management expects a loss of $105 million to $115 million. 

Now what 

Higher natural gas prices and lower environmental credits hurt results, according to management. But that highlights the problems that Clean Energy Fuels faces long-term. It doesn't have a sustainable competitive advantage in the fuel market right now and is dependent on a commodity arbitrage to make the economics work. When commodity prices move away from the company, it loses money. 

Environmental credits are also not a sustainable source of revenue or earnings long-term. They will eventually go to zero or get competed away as more capacity is brought online. The business continues to show that it's tough to make money at a time when energy profits are at all-time highs, which is why I'm staying out of the stock today.