The new Tesla is a huge step forward for its electric car rival

Elon Musk’s Model S, the electric car he co-founded in 2003, is the most powerful electric car in the world.

Its first mass production model, the Tesla Roadster, will go on sale this year.

But the next Tesla, the Model X, has a lot of advantages over it, not least of which is that it’s more fuel-efficient than the previous one.