Hydrogen sourced from green electricity can increase the share of renewables in the transportation sector and reduce particulate matter and nitrogen oxide emissions. There is a catch, though – green gas production is still too expensive. The Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW) and its partners recently tested an option on a research platform that could help cut costs.Gradually replacing fossil fuels with renewables in electrical power stations is a start, but the same will have to happen in transportation and buildings. Hydrogen is the perfect enabler for this transition. This gaseous energy carrier can buffer surplus green electricity for other sectors to use. Germany’s exit from fossil fuels in transportation and heating has slowed to a crawl; hydrogen could get things rolling again.
Same footprint, but more powerful – the new electrolyzer
Electrolysis plants use electricity to break water down into hydrogen and oxygen. As it stands, the process is too expensive for green hydrogen gas to be competitively priced. Seeking to drive down these costs, ZSW researchers and their partners in science and industry recently set up a research platform at an industrial one-megawatt plant on the Upper Rhine River. The larger goal is climate-friendly mobility.
Initial trials with this research electrolyzer went well. The project partners ZSW and the German Aerospace Center (DLR) achieved a 20 percent increase in power density using new electrode coatings. This means the plant is able to generate a fifth more hydrogen than an industrial plant of the same size and with the same energy consumption. To put it another way, the new electrolyzer can achieve the same performance using less space and material. However, the researchers still have to substantiate the advanced electrode coating’s durability.
This research initiative is part of a lighthouse project called Power-to-Gas Baden-Württemberg launched in November 2018. The power company Energiedienst AG aims to operate an electrolysis plant to produce hydrogen on an industrial scale at Wyhlen in the south of the German Baden region. The commercial plant, up and running on a trial basis since November 2018, can now produce around half a metric ton of hydrogen per day – enough fuel for more than 1,000 fuel-cell cars’ average daily trips. The ZSW scientists’ research facility is connected to this plant and also operates under real-world conditions. A neighboring hydropower plant on the Rhine River furnishes the electricity for both facilities. Once the two electrolysis units convert water into hydrogen, their yield is merged and trucked to the point of use.