Hydrogen is the most abundant element in the universe. It powers the sun and is used a rocket propellant by NASA. Imagine if it could power your car.
Benefits of using hydrogen
The benefits of using hydrogen as a fuel read like a wish list for the perfect fuel. It burns cleanly and produces no harmful by products – only water; and it can be extracted from water by electrolysis. Taken at face value like this, if we moved to a hydrogen-based fuel economy, we’d have a virtually infinite supply of free fuel and no vehicle pollution. So why don’t we have more hydrogen powered cars?
The hydrogen economy has been politician’s dreams for decades. George W. Bush was a champion, seeing hydrogen as a way to free America from the influence of Middle East oil nations. Car manufacturers have invested billions in hydrogen research, only for some to become disillusioned with the technology and pull funding. Why is it so difficult?
Hydrogen is actually quite difficult to produce. The main method of extracting it is through a process called steam reforming of methane gas. But this is energy intensive, and produces 12 kilos of carbon dioxide for every 1 kilo of hydrogen. The ideal method would be to produce hydrogen from the electrolysis of water, using renewable energy to power the plants.
Then there’s the actual technology required to use hydrogen as a fuel. Hydrogen powered cars (called fuel cell vehicles) use a fuel cell to power them. This differs from battery-powered cars which can be recharged by plugging into the mains electric. And if you think battery-powered vehicles have drawbacks, hydrogen fuel cell vehicles are in some ways even further behind.
A fuel cell vehicle has a fuel cell stack which combines hydrogen and oxygen to generate electricity. But you need a lot of hydrogen to get a decent driving range. The gas has to be highly compressed –the whole trunk of a car would be taken up with compressed gas cylinders. There are concerns that tanks could explode if ruptured in an accident, and the compressed gas is highly combustible – think Hindenberg airship disaster…
The fuel cell stack needs precious metals so they’re expensive to produce. And the technology is nowhere near mature to justify large-scale manufacture, although the cost of fuel cells is slowly dropping.
Another problem is the lack of a distribution system for hydrogen. The infrastructure for moving and storing petroleum is mature; replacing it with a new hydrogen infrastructure would cost billions of dollars.
The reality of hydrogen as a limitless, free fuel is unfortunately still many years away. Some doubt it will ever be achieved.