A Tesla Model S has been hacked in the Netherlands to allow the electric car to run off a second fuel supply – hydrogen cells.

Gas supplier Hulthausen Group claims it has doubled the Tesla Model S's range from about 300 miles per charge to 620 miles. "Project Hesla", as it was dubbed by the company's founder, sourced a second-hand Model S and made the modifications without involvement from Tesla. The hack uses the car's electrical mainframe and adds a second layer of charging via hydrogen cells.

Company engineer Max Hulthausen described the process as a "big maze" because Tesla cars do not accept an external power source. But as tempting as increased range is, interested customers face heavy drawbacks.

Refueling the hydrogen battery will become tricky as there are only seven public refuelling stations across the UK. There are an extra four at universities, but these require an appointment. The United States has 39 public stations across four states.

Price will also be a deterrent. The Tesla Model S starts at £64,700 and can rise all the way to £122,200. The cost of installing the hydrogen power source is about £44,000. If owners really want to go far and fast in their cars, a Model S P100D could end up costing them about £170,000.

Tesla is having its own issues at the moment, as manufacturing delays scupper the release of the new Model 3. The "affordable" electric car was meant to be delivered to first buyers by the end of 2017, but owner and founder Elon Musk has confirmed deliveries will not take place until at least March 2018.

About 500,000 Model 3 cars have been ordered worldwide, but only 260 were built in the third quarter. Musk and financial chief Deepak Ahuja said in a letter to shareholders that it was hard to prepare for production problems.

"The nature of the manufacturing challenges during a ramp such as this makes it difficult to predict exactly how long it will take for all bottlenecks to be clear or when new ones appear. There can be large forward jumps from one week to the next."