Elon Musk's Tesla unveils its first electric lorry

Tesla has unveiled its first articulated electric lorry with production due to begin in the US in 2019.

Elon Musk, the company's billionaire chief executive, said the Semi truck is capable of travelling 500 miles on an electric charge.

The tech entrepreneur also said it will cost less than a diesel counterparttaking into consideration fuel savings, lower maintenance and other factors.

"We're confident that this is a product that's better in every way from a feature standpoint," he told a crowd of Tesla fans in California.

Mr Musk did not reveal the vehicle's price but said customers can put down a 5,000 dollar (£3,778) deposit.

Key features

The truck will have Tesla's Autopilot system, which can maintain a set speed and slow down automatically in traffic.

It also has a system that automatically keeps the vehicle in its lane.

Mr Musk said several Tesla lorries will be able to travel in a convoy, autonomously following each other.

The company also plans to create a global network of solar-powered "megachargers" that could get the trucks back up to 400 miles of range after charging for only 30 minutes.

An animation of how the lorries would travel in one lane in convoy. Credit: Tesla

The electric car maker also surprised fans with an updated version of its first sports car, the Roadster.

It said the new edition will have 620 miles of range and a top speed of 250mph.

The car, due in 2020, will have a base price of 200,000 dollars (£150,000).

Tesla has been making cars for more than a decade - and more recently, solar panels.

It now looking to diversify into big trucks to help its goal of shifting to sustainable transport.

Mr Musk is involved in many other projects and announced plans he says could allow his SpaceX company to colonise Mars in September.

The tech entrepreneur's projects also include high-speed transit, artificial intelligence research and a new company that is digging tunnels beneath Los Angeles to alleviate traffic congestion.