Will hydrogen power take off?
For almost two decades, the world has been tantalised by the idea of hydrogen fuel cell electric vehicles (FCEVs), with ample range and no tailpipe emissions except water and heat. Now the chances of the hydrogen fuel cell car gaining a major foothold by 2040 are improving.
“If the hydrogen infrastructure business model works and the car manufacturers become serious, there could be a significant ramp-up after 2020. You could be looking at millions to tens of millions of cars by 2040,” says David Hart of sustainable energy consultant E4Tech and former head of fuel cells at Imperial College.
Hart rates the leaders in the field as Toyota, Honda and Hyundai. Toyota’s Mirai has the same “skeleton” as Toyota’s hybrid models, but what’s different is the power source, says Toyota fuel cell specialist, Julien Roussel. A hydrogen fuel cell feeds electricity to a buffer battery, which provides the transient response to the accelerator pedal for acceleration and stores electrical energy recovered by regenerative braking. “This is the ultimate evolution of our core hybrid technology,” Roussel explains.
A fuel cell ‘stack’ contains hundreds of the small individual cells converting compressed hydrogen and airborne oxygen into electricity, with only heat and water as by-products. Hydrogen is stored in carbonfibre tanks at a pressure of 700bar. Manufacturing both was once labour-intensive, but Toyota has reduced manufacturing costs by introducing automation and producing everything, including the carbonfibre hydrogen tanks, in-house.
The energy density of hydrogen storage on board is around five times higher than that of today’s battery technology by weight and the Honda FCV Clarity introduced last year has a range of 435 miles on one fill. Refuelling time is equivalent to that of petrol or diesel and hydrogen fuel is at least as safe to use as the other two.
Building an infrastructure of hydrogen filling stations remains a challenge to the large-scale adoption of FCEVs. By the end of 2016, there should be around 200 hydrogen filling stations globally. “A hydrogen infrastructure is difficult to scale up, but once it’s there, it’s a profitable business in its own right,” says GM fuel cell expert Ritmar von Helmolt. “Recharging stations for electric vehicles are not, because the cost of operating them is significantly more than the cost of the energy being sold.”
There’s plenty of global investment. In Europe, £1 billion has been budgeted to support hydrogen and fuel cell development from 2014 to 2020.
Will I still be putting petrol or diesel in my car?
Fifteen years ago, the oil industry warned that oil could become uncomfortably expensive to extract by 2040 and that some oil-producing areas could begin to dry up. Today, the story has changed.
According to BP, fossil fuels are going to become cheaper and easier to extract. Between now and 2050, BP estimates there are 4.8 trillion barrels of ‘oil equivalent’ energy (oil and gas) that can be recovered using today’s technology and the projected demand to 2050 is 2.5 trillion barrels. A further 2.7 trillion could be available through new discoveries and improved technology.
BP is less optimistic about the uptake of radical new technologies such as the hydrogen fuel cell and thinks the global energy demand for transport until 2035 and beyond is likely to be met largely by liquid fuels.