(REUTERS) - PepsiCo has reserved 100 of Tesla's new electric Semi trucks.

That is the largest-known order for Tesla's big rig.

PepsiCo says the trucks will complement its fleet of nearly 10,000 and help reduce fuel costs and emissions.

A dozen other companies, such as Wal-Mart, fleet operator J.B. Hunt, and food service distribution company Sysco, have put in their orders for Tesla's Semis.

The total number of orders comes up to 267 trucks, according to a Reuters tally.

Cox Automotive's senior manager of insights and analytics, Mr Akshay Anand, says: "The Semi and the Roadster looked wonderful, but the Model 3 is their immediate pressing concern. We know there are production issues, and they need to get the model right, so they don't spread themselves too thin. So, I think, over the next year, you know, year and a half, whatever it is, the Model 3 is the most critical piece for Tesla's future success. And we'll see how the Model 3 does. I think that'll kind of dictate where they go with Semis and Raodsters."

Tesla unveiled the Semi last month. It expects the truck to be in production by 2019.

The company is going for a big market. About 260,000 heavy-duty trucks are produced in North America every year, according to research firm FTR.