In the wake of the earthquake and tsunami, the Nikkei Stock Average in Japan is taking a plunge. The disaster is also having an impact on the American economy.

Japan is one of the world’s largest consumers of natural gas.

“That means that the Japanese economy and their power plants are only going to be that much thirstier for natural gas and that should all else equal raised natural gas prices.” said Paul Larson, equity strategist with Morningstar.

Larson says in the short term Japanese companies with factories in the US could feel an impact on a smaller scale.

Subaru and Toyota are suspending overtime at their plants in Indiana. Mitsubishi says it has enough parts to build cars in central Illinois for the next 2 weeks, but it’s uncertain if the company will halt production.

Meanwhile, Chicago-based Exelon Corporation took a dip in the stock market. But Larson says Exelon could actually end up with a mild net positive because the company will likely have less competition with its existing nuclear facilities in the future.

But not all markets will take a hit. Larson says Illinois-based Caterpillar could see an uptick in production as major cleanup efforts in Japan begin.