The development of the world’s first "infinity train", which will use electric and gravitational energy to never run out of juice, has been announced by an Australian mining firm following their acquisition of an advanced engineering firm.

The move pushes forward their goal of zero emissions – a difficult task for a company transporting vast quantities of iron ore. 

But how can a train with seemingly infinite energy exist? According to Fortescue and the newly-acquired Williams Advanced Engineering (WAE), the train will be battery-powered on the way to its destination, which has a downhill gradient sufficient to regeneratively charge the battery enough for the return journey.

This idea utilizes gravitational energy to recharge the battery while it is loaded with the extreme weight of 34,404 tonnes of iron ore in 244 ore cars, so that when it empties and becomes significantly lighter, it can easily return to its origin without manual recharging.

“The Infinity Train has the capacity to be the world’s most efficient battery electric locomotive. The regeneration of electricity on the downhill loaded sections will remove the need for the installation of renewable energy generation and recharging infrastructure, making it a capital efficient solution for eliminating diesel and emissions from our rail operations,” Fortescue Chief Executive Officer, Elizabeth Gaines said in a statement. 

Fortescue, as the fourth largest iron ore company in Australia, consumed 82 million liters of diesel last financial year, and believes the new technology may begin to curb their emissions. 

Gravity as an energy source, or energy storage in gravity batteries, is not a new concept – although it is yet to see widespread implementation. Most modern cars now have regenerative braking, a system that uses the friction of slowing down the car while braking to then recharge the battery. This may be utilized in the Infinity Train.

An energy storage facility in Nevada began construction in 2020 that will use leftover renewable energy to push large trains uphill, storing that energy as gravitational potential energy to be released as per demand. It is unclear how successful this will be, although the company claims it will hold 50 Megawatts of energy.  

However, gravity energy has never been utilized on a train such as this. If it is successful, could revolutionize the cargo industry. 

“The Infinity Train continues FFI’s inexorable march to change the world’s attitude to energy generation. To move business leaders and politicians globally to the realisation that fossil fuel is just one source of energy and there are others now, like gravitational energy, rapidly emerging, which are more efficient, lower cost and green. The world must, and clearly can, move on from its highly polluting, deadly if not stopped epoch of fossil fuel,” Dr Andrew Forrest AO, Founder and Chairman of Fortescue, said in a statement.