What happened 

Shares of natural gas distributor Clean Energy Fuels Corp (CLNE 4.53%) have had an outstanding start to 2018, climbing 81.8% in the first half of the year, according to data provided by S&P Global Market Intelligence. But some of those gains were given back early in July with the stock down 23.3% in the first 10 days of the month.

So what 

Clean Energy Fuels stock started shooting higher in early May when it was announced that oil and natural gas giant Total had agreed to invest $83.4 million in the company, taking a 25% stake. The companies also agreed to push for more heavy-duty truck deployments, including a leasing program that Clean Energy Fuels will administer and Total will support. Shareholders quickly approved the investment in early June. 

Natural gas tanker on the highway.

Image source: Getty Images.

As much as investors liked the Total agreement, it hasn't changed the fundamentals for the company yet and that may be why share prices have come crashing down in July

Now what 

At the end of the day, the Total investment has to prove fruitful if it's going to continue to drive share prices higher long term. Clean Energy Fuels is going to have to turn around the $128.1 million in net losses it's reported in the past year, and with volume sold flat in the most recent quarter, there doesn't appear to be much momentum in the natural gas fuel business. While traders were excited about the Total deal after it was announced, long-term investors should look for a fundamental improvement in the business before getting too excited about the investment. When the rubber hits the road, there's no guarantee Total can turn Clean Energy Fuels around.