“Battery-powered electrical drives won't be able to serve many applications in the off-highway business which means they won't be able to power the largest off-highway vehicles. That's something we're pretty sure of,” said Dr. Peter Riegger, Vice President of PowerLab at Rolls-Royce Power Systems.
Fuel cells, on the other hand, are highly promising – for both mobile and power generation applications where high energy density and large energy quantities are required. The only difference is that the electric motor is driven not by batteries, but by a fuel cell. Inside the fuel cell, a controlled chemical reaction takes place between hydrogen and oxygen, producing electricity that powers the electric motor. Emissions are almost non-existent – just water vapor. Only a small amount of heat is given off, which is why what happens in the fuel cell stacks is also referred to as 'cold combustion'.
Developing fuel cell systems ready for market
“In a few years' time we'll be supplying fuel cell solutions,” says Riegger. They promise exactly what we all need for a green future: zero-carbon mobility and zero-carbon power generation. Another major advantage of fuel cells over internal combustion engines is that they are scalable and extremely versatile in applications, meaning that if more power is needed, more fuel cell modules can be added on.
This also happens in operation: To date, propulsion power – for example in ships – is produced mainly by diesel engines whose power rating has to correspond to the vessel's maximum power requirement. Fuel cells, however – especially when combined with batteries – open new possibilities, allowing the vessel to constantly adapt the amount of power being generated to match its current power requirement, saving fuel in the process. When a lot of power is required, all fuel cells are used, but when the ship is at low speeds, some fuel cells can simply be switched off.