Researchers from the Federal Institute of Technology Lausanne have presented a novel hydrogen storage and refueling system. This could help the clean energy to achieve a long-term breakthrough.
The fossil age will end. And not because the oil reserves will be burnt. But because new techniques and materials are available. “The Stone Age did not end because it no longer had any bricks,” says Andreas Züttel, a professor at the EPFL in Lausanne.
This will be the same as fossil fuels. “World energy consumption of 18 terawatts will be possible in 2030 through renewable energy sources. But only if we are able to store renewable energy, “says Züttel.
Because renewable energy has the disadvantage of cycles. Sun and wind are not always and certainly not even available. That is why the energy turnaround stands and falls with storage, for which new forms are sought all over the world. Yesterday, the EPFL professor, together with Hans-Michael Kellner, CEO of Messrs. Schweiz, presented a technique in Zurich that could greatly simplify hydrogen utilization and storage.
Oil is easy to store in barrels
Because still has in terms of storage, the oil with its energy density ahead. Three barrels of oil can be used to heat a house for one year, drive a car for a month. For comparison: It needs 1250 car batteries. Even more energy density than oil has hydrogen (H2). Already 33 kilograms are enough for the above-mentioned services.
However, there is the problem of volume, because without the compression under high pressure it takes for the storage of these 33 kilograms of hydrogen, the volume of a giant balloon with 13 meters in diameter.
That’s why hydrogen has to be compressed and released several times to transport it and then use it in a vehicle. However, this repeated compression needs a lot of energy itself, which results in high electricity costs. Furthermore, the production of hydrogen generates much noise and strong vibrations, because pistons compress the gas under great force, as in a marine engine.
Many people are not even aware of this noise development at hydrogen refueling stations, because the only two current hydrogen refueling stations in Switzerland are not in the vicinity of residential areas, says Züttel. Until a hydrogen car can be fueled, so many and complex steps are needed.
Zuttel’s system enables storage and compression of hydrogen in one step. This is possible with a metal hydride, which absorbs the hydrogen-like a sponge. This allows the pressure of hydrogen to be regulated by temperature, not by the use of electricity.
«This is a huge advantage for refueling vehicles»
explains Züttel. This refueling chain never creates a high pressure, which is a potential hazard. In the refueling system with the metal hydride called HyCo, the high pressure required for driving a car arises only when refueling the hydrogen car. The system is noiseless and vibration-free, needs no electricity but only heat. This can come from an industrial metal hydride use, for example, from waste heat of a company.
The global Messer company, which is active in the H2 economy and also in CO2 recycling, wants to use the development of EPFL industrially. With HyCo, hydrogen refueling should not only become cheaper and more efficient at filling stations. “The process is even more interesting for small amounts of hydrogen,” says Kellner. In the future, it should, therefore, be possible to carry out the production of hydrogen with conventional electrolysis and the storage in metal hydride at each private house. Each his own H2 gas station.
The densest petrol station network
Kellner speaks of the densest filling station network in the world when hydrogen can be fueled on every corner. Because water is available without end and with the chemical hydrogen compressor from Lausanne the system can be installed everywhere. Probably not first for single-family homes, but for parking garages and companies.
There are already standard hydrogen cars, which have a range of about 600 kilometers. One pioneer is the manufacturer Hyundai, which is working together with the ETH Lausanne on the H2 storage tank.
It will take some time before the system becomes widely accepted. Although the HyCo laboratory device works well, it still has to be scaled to industrial size. On the other hand, the political course for such hydrogen use has not yet been set. And so Züttel and waiters see the danger “that we are presenting this technique here for the first time, but unfortunately, another country is faster.”
In the long run, the two see hydrogen as the solution that will survive all current drive types, among other things because hydrogen has a higher energy density than a battery.