Could Hydrogen Replace the Need for an Electric Grid?
As a solution to climate change, hydrogen is starting to attract a lot of attention — and investment. The element is the most abundant chemical substance in the universe and is already used as a feedstock in refineries and the chemical industry. But it is hydrogen’s potential as an energy carrier, capable of transporting large amounts of energy over long distances, that is generating the most excitement.
BRINK spoke to professor Ad van Wijk, who has been described as one of the pioneers of the hydrogen economy, and is professor of Future Energy Systems at Delft University of Technology, about the current state of the technology.
AD VAN WIJK: At present, most hydrogen is generated from fossil fuels, mainly from natural gas but also from coal; that creates carbon dioxide emissions when you produce the hydrogen. This is called grey hydrogen. Hydrogen is mostly used as a feedstock in the chemical industry, for example, to produce ammonia/fertilizers, and also in refineries to crack and desulfurize oil.
However, the future of hydrogen is as an energy carrier.
One of the best applications is in heavy transport — as a fuel in ships, long-distance trucks and trains that are not electrified. You can put ammonia, a hydrogen product, into a diesel engine, and even directly inject hydrogen itself into the air inlet of a diesel engine. For example, two months ago, we launched the first tractors with directly injected hydrogen in the engine in the Netherlands.
For a ship, it is a bit different because it is difficult to carry enough hydrogen in compressed form for long journeys. But for most coastal vessels, you can store enough energy, and the first ships are now being converted.
No Need for an Electric Grid
BRINK: How feasible is it today to create hydrogen to scale with zero carbon emissions?
AD VAN WIJK: Hydrogen can be produced from water by electrolysis, whereby the water molecule is split into hydrogen and oxygen, and the hydrogen is captured. When the electricity for doing this is coming from solar or wind, then it’s completely clean — so-called green hydrogen — but when the electricity comes from fossil fuels like coal-fired power plants, it is called grey hydrogen.
You need a combination of large scale solar and wind installations connected to the electrolyzer to create green hydrogen. These hydrogen production plants, as we call them, don’t need to be connected to the electricity grid. The electricity from the solar or wind is converted directly into hydrogen, which is used to transport the energy long distances instead of electric pylons.
When you do that at large scale at good resource sites, for example, solar farms in North Africa, you get a very high yield. Today, it is possible to produce electricity for almost 1 cent per kilowatt-hour with solar. When that is converted into hydrogen, the price for the hydrogen is about one euro, or $1 per kilo, which is competitive with even the gray fossil fuel hydrogen.
Hydrogen’s Potential As an Energy Carrier
BRINK: How do you move the hydrogen from the solar farms?
AD VAN WIJK: By pipeline. That’s the interesting thing: It is about 10 times cheaper to transport energy by a hydrogen pipeline than by an electric cable. That makes it possible to transport electricity very cheaply from somewhere like North Africa to the demand centers in Europe, for example.
Hydrogen is a very modular technology: There are no rotating parts and no high temperatures; it therefore promises to be much cheaper than combustion technology.
At its destination, you can use the hydrogen directly as a fuel. But you can also transport the hydrogen to a power plant, convert it back to electricity, and then distribute the electricity through the local grid.
For economic reasons, it is much better to transport energy over long distances by molecules. When you transport hydrogen over a distance of about a thousand miles by pipeline, the costs are about half a cent per kilowatt-hour. When you do the same with electricity, it is about 5 cents per kilowatt-hour.
The Promise of Hydrogen Fuel Cells
BRINK: You mentioned fuel cells. How advanced is the technology for creating them?
AD VAN WIJK: The fuel cell technology is the reverse process of electrolysis, you could say; fuel cells and electrolyzers do opposite things. They are more or less the same technology — the only thing is, you reverse the process.
Fuel cells have a lot of promise for mobility because you don’t have any tailpipe emissions, and they offer much higher efficiency than combustion technologies. Also, with hydrogen you can fuel your car in four or five minutes, the same as diesel or gasoline engines.
That is why car manufacturers are developing fuel cell technology for their larger cars — and especially for buses and trucks. Once this is done on a mass scale, the cost of these fuel cells will come down to about $30 to $50 per kilowatt fuel cell system.
Hydrogen is a very modular technology. It’s really quite a simple thing. Unlike a combustion engine, there are no rotating parts and no high temperatures; it therefore promises to be much cheaper than combustion technology which has a lot of costly materials.
Fuel Cells Ready for Mass Production
In five to 10 years, fuel cells will start replacing combustion technology such as diesel engines. A fuel cell converts hydrogen electrochemically into electricity, and the electricity is then used to drive the car or the propellers of the ship. So you don’t have any other emissions like the nitrogen oxide that you have with a combustion engine.
Ten years ago, the fuel cells were too heavy and too large and didn’t have the right lifetime, but in the past few years, car manufacturers like Toyota and Hyundai have developed fuel cells that are ready for mass production.
The fuel cell technology can also be used for so-called electricity balancing, when you don’t have enough electricity produced by solar and wind. And today in Japan, Panasonic is even making very small fuel cells for homes for when your solar panels are not sufficient. They can also potentially be used for home heating.