The hydrogen color theory gets another swab: dark green. By this, the German Advisory Council on the Environment (SRU) means that green hydrogen “whose production meets minimum ecological and social standards”. After all, if green hydrogen is produced, it interferes with the environment, because large amounts of renewable electricity are required.
“These environmental impacts must be kept as low as possible,” says a statement by the Environment Council entitled “Hydrogen in climate protection: class instead of mass”. This applies all the more to Power-to-X (PtX) follow-up products such as ammonia and synthetic fuels, because they incur additional conversion losses.
In the case of imports of green hydrogen, it must be ensured that the transformation of the energy systems in the producing countries is not delayed and that no additional social problems or environmental impacts arise, the experts continue, seven university professors who advise the federal government. You propose a certification system that contains “demanding sustainability criteria”.
Green, gray, blue, turquoise
Green hydrogen is made by electrolysis of water. Only electricity from renewable energies is used. There is also the gray hydrogen, which is obtained from fossil fuels. If CO2 is deposited and stored, the hydrogen is blue. It is turquoise when it is produced via the thermal fission of methane (methane pyrolysis). Instead of CO2 solid carbon is created in the process. Yellow hydrogen is made from a mix of electricity, pink from atomic electricity.
In the opinion of the experts, blue hydrogen is not suitable as a transition technology, as the new infrastructure required for it would delay the long-term transformation to renewable energies. “Instead of in CO2Investing in capture and storage should now quickly create favorable conditions for the market ramp-up of green hydrogen and the overall energy requirement should be reduced. “
Inefficient hydrogen
Hydrogen is particularly important for the chemical industry, the steel industry and international shipping and air traffic in order to become carbon-neutral. It is still unclear whether hydrogen or electrification through batteries and overhead lines will prevail in heavy-duty traffic. According to the Environment Council, hydrogen should only play a supplementary role in the electricity system and in heating networks. For building heating and in car traffic, however, the use of hydrogen is inefficient and significantly more expensive than direct electrification using heat pumps and battery-electric vehicles.
“The necessary phase-out from the use of natural gas and crude oil must be prioritized in order to avoid further bad investments in fossil technologies and to initiate the necessary transformation,” the statement said. In addition, an integrated network planning of the infrastructures of hydrogen, natural gas and electricity, which is based on the existing climate targets, is required. Green hydrogen should be promoted where it is needed in the long term.
At the end of May of this year, the federal government announced to which 62 projects for the use of green hydrogen 8 billion euros are to be distributed. The government aims to become number 1 in the world in hydrogen technology.
(anw)
