The pathway to hydrogen cars
At the start of the Olympics, a story appeared in some news sources sneering at the fact that London’s new hydrogen-fuelled taxis had to be transported to Swindon to be refuelled, negating any carbon saving they provided. While admittedly something of a PR blunder, this wasn’t quite the failure of planning and technology that those who wrote the articles tried to portray it as: the London refuelling station was merely a day late in opening and the taxis had already been booked to carry VIPs across the capital.
When it comes to hydrogen and other low-carbon energy alternatives, it’s common to hear sceptical scoffing like this. ‘It’ll never be cost-effective,’ the naysayers exclaimed. ‘It’s not made with renewable energy so what’s the point?’ Of course, these are issues that have to be addressed if hydrogen is to become a viable way of cutting CO2 emissions. But getting to that point requires intermediate steps. It requires companies willing to invest for the long term and to develop production and distribution systems that minimise losses and can pave the way for genuinely green hydrogen.
‘We’re using brown hydrogen [from non-renewable sources] to demonstrate the technology and to improve the infrastructure,’ said Diana Raine, European business manager for hydrogen at Air Products, the company that supplies the gas for the London taxis. ‘When the market is there, then we’ll invest in green hydrogen but we can only do that if the pathway to green production is there.
‘We want to prove the technology at the lowest possible cost. The London refuelling station uses brown hydrogen, which provides a 50 per cent CO2 reduction compared with existing taxis. But we’ve made a commitment up front with Transport for London to improve the existing production line and eventually go green.’
According to rough market projections made by sustainable energy consultancy E4tech, there could be 1.5 million hydrogen cars on the road globally by 2020 and 35m by 2030. How will this happen when battery and plug-in hybrid electric vehicles (EVs) are already starting to creep into the market? E4tech director David Hart, who is also a principal research fellow at Imperial College London, argues that hydrogen will target a section of the market that EVs can’t reach.
‘A pure EV makes sense for a limited range where you have the capability to recharge slowly because it’s the most efficient way of converting renewable electricity into transport fuel.’ But for people who consistently travel long distances, a hydrogen vehicle would be much more suitable because it doesn’t need filling up as often and that process, at around three minutes, is much quicker than recharging a battery.
A recent EU study found that, based on current driving patterns, battery-powered EVs would only be able to replace 50 per cent of cars in Europe. This represents only 25 per cent of vehicle emissions because larger cars used more for long journeys produce far more CO2.
Add to this the developing markets for public transport, forklift trucks in warehouses, low-carbon generators for back-up supplies and remote operations such as mobile phone masts and even internal power systems for submarines, and the reasons for (eventually) investing in green hydrogen production become even stronger. There’s also the prospect of energy storage — an undeveloped sector but one that will be vital for managing the intermittency of renewable electricity generation.
Although genuinely green hydrogen isn’t yet widely available, industrial gas companies do have potential solutions in the pipeline. Already in the process of replacing production facilities with more efficient designs to cut CO2 emissions by up to 20 per cent at each one, Air Products is also developing plants that use waste gas as their feedstock.
Following the opening of a biogas-fuelled power, heat and hydrogen facility in California, the company is preparing for a 2014 opening of the Tees Valley Renewable Energy Plant, which will gasify landfill waste to produce syngas for electricity generation. The company then intends to modify this design for another UK plant outputting hydrogen.
Of course, hydrogen has its disadvantages. Refuelling facilities tend to take up a lot of space and use energy to keep the fuel compressed or liquefied. There are regulatory barriers because current standards are based on industrial usage. It’s also difficult to meter and you can’t add an odorant as is done with methane without making it unsuitable for fuel-cell use.
Hydrogen transport is one of those technologies that’s always referred to as being just a few years away — and has been for 20 years. But with several major manufacturers, including Toyota and Daimler, announcing their intentions to make hydrogen cars commercially available by 2015, it seems that this forecast may finally have become accurate.