BMW has announced a hydrogen fuel-cell car that has a range of 700km, charges in less than five minutes, and is emission-free other than water. If this sounds like a car that could save the world, that’s because it is. In theory.

The concept of using hydrogen to fuel a car isn’t new; BMW says its been working on the technology for 30 years. In fact, it’s already been beaten to the fuel-cell market by the Toyota Mirai – due out later this year – and 2008’s Honda FCX Clarity.

What’s important about today’s development can be broken down into three parts. First is BMW’s cryo-compressed hydrogen storage vessel (we’ll come to that later). Next, how this efficiently works with BMW’s fuel-cell technology. Finally, the Western world’s push towards renewable energy and how that can help cars.

The cryo-compressed hydrogen storage vessel is similar to the one found in the Toyota Mirai and it’s best to think of it as the hydrogen equivalent of a petrol tank. The vessel weighs 160kg (including fuel), has a maximum storage capacity of 7.1kg, and is designed to sit between the front and rear axles – meaning it’s unnoticeable from the cockpit. BMW reports that it can keep hydrogen cooled to -220˚C and ready for immediate use for six weeks.

I recently got to test drive an adapted 5 Series Gran Turismo at BMW’s Miramas test track. Other than it being a little noisy (I was assured no “acoustic engineering” had been done yet), it was very comfortable – an unremarkable driving experience, which I mean as a compliment. As you’d expect from an alternative eco-friendly fuel source, the performance didn’t break any speed records, but it was fast enough (for me), going from 0-100km/h in six seconds.

Another attraction of a fuel cell as a power source is the cost. The current price of hydrogen at the pump, in Germany, is roughly €10 per kilogram. BMW’s cryo-compressed hydrogen storage vessel has the capacity to store 7kg of liquid hydrogen. In real-world terms, that means you can completely refuel for €70 (£50) and then drive 700km (434m). Not bad.

For BMW’s hydrogen-powered cars to be successful, there needs to be the supporting infrastructure in place to facilitate it. The way BMW envisages this working is to use power from renewable energy sources, such as wind farms and solar panels, to create hydrogen. The next step is to transport the freshly made hydrogen to refuelling stations – just like regular petrol – to be made available to car drivers.

This is where things get interesting. Germany is one of the best-performing renewable-energy economies, producing more than 30% of the nation’s electricity this way. For those keeping score, the UK is ahead of schedule to hit its EU-set renewable-energy target of 30% by 2020 (as a whole) – yet transport emissions rose by 1% last year.

However, one of the major problems with generating electricity from renewables is that it’s a feast or famine industry, solely dependant on the current weather. Storing energy created during favourable weather is key to renewable-energy success.

BMW highlight that the more Germany moves towards renewable energy, the more it will overproduce and waste power. The car manufacturer predicts that, as a nation, renewable-energy sources will produce an excess of electricity to the tune of 40TWh over a two-week period – or, in more measurable terms, enough to power 200 billion kilometres of CO2-free driving using hydrogen fuel-cell technology.

Be that as it may, it’s still a long way off. For this technology to be a successful for the automotive industry, the infrastructure needs to be vastly improved. In Germany, one of the greenest developed nations, there are plans for only 50 fuelling stations to be made hydrogen-ready by the end of 2015. BMW says this number will increase to 400 by 2023. And even though this technology is aimed at cars making regular mid- to long-range journeys on motorways (presumably where the majority of these stations will be located), this still falls a long way short of the number of regular petrol stations.

Does this mean you shouldn’t be optimistic about the technology? Absolutely not. Plugin and hybrid cars have been a great success so far, proving that demand is there for “greener” cars. Hydrogen fuel-cell cars offer a viable way to power a car, without producing any carbon emission once they hit the road.

I’m very excited about the possibilities of this technology. It’s now up to the powers that be to make green fuel sources, such as hydrogen, as convenient to access as petroleum. If and when that happens, we could see gas-thirsty cars replaced within a generation… and be a step closer to saving the world at the same time. That’s nice.