Jonny learns more about ITM Power's high-volume stack (behind, left)
Something that is emerging as a key theme at this year’s Group Exhibit, and which featured prominently today, is power-to-gas, which describes the use of excess electricity to generate hydrogen, which acts as a scalable energy store. The hydrogen can be injected, stored and distributed through the existing natural gas grid, which in many countries already transmits significantly more energy (in kWh terms) than the electricity grid and hence has substantial potential for energy storage. The scope of the concept is genuinely exciting and is attracting plenty of interest.
Raphaël Goldstein is the Senior Manager for Energy Storage/Fuel Cell Systems at Germany Trade and Invest, which works to foster international partnerships with German companies. It is now discussing power-to-gas with prospective investors as there are solid reasons for adopting such a system in Germany: the gas grid has 2,000 times more storage capacity than the country’s pumped storage reservoirs, the common energy storage medium. This is capacity that will be sorely needed as the proportion of variable renewable sources in the energy mix grows: the government target is 80% by 2050. The rapid uptake of domestic solar PV in Germany is already putting pressure on the electrical grid in some regions, and grid restrictions are also leading to the loss of otherwise valuable wind energy during periods of oversupply.
Current regulations permit the injection of hydrogen into the German natural gas grid up to a level of 5 vol.%; this may not sound like much but it actually represents significant storage capacity. Pushing this up to 10% should be relatively straightforward, with the necessary validation and approvals. However, pipelines are not the only place to store hydrogen: significant capacity exists in underground salt caverns, which are already being used for natural gas storage and are thus grid-connected.
The key to unlocking the potential of power-to-gas is electrolyser technology. The German Aerospace Centre (DLR) is working on several projects to develop electrolysers that work well with the fluctuating supply characteristic of renewable electricity sources – it says both alkaline and PEM electrolysers can be suitable for this application, and offer different advantages. (Yesterday we also heard from Staxera and Sunfire, who are working together on a system that uses a solid oxide electrolyser).
Hydrogenics announced today that it will be working with Enbridge, Canada’s largest natural gas distribution company, to develop a power-to-gas storage system using Hydrogenics’ electrolysers to generate hydrogen from renewable electricity which is then injected into the gas grid in small quantities, also pushing up the renewable content of the gas.
Power-to-gas is receiving increasing attention around the world; in addition to Hydrogenics there are several other prominent electrolyser manufacturers at the Exhibit this year, including NEL Hydrogen, Acta, Proton OnSite and ITM Power.
ITM Power in February announced the launch of a 1 MW electrolyser system based on a new high-pressure high-volume (25 kg H2 per day) stack, which it is exhibiting throughout the week at the Group Exhibit. The system is scalable in a modular fashion and is being specifically targeted at power-to-gas applications. The company was awarded a grant by the UK Technology Strategy Board (TSB) earlier this month alongside the Scottish Hydrogen & Fuel Cell Association (SHFCA) and GASTEC at CRE to investigate the technical, financial and operational feasibility of injecting hydrogen from electrolysis into the UK gas grid. The company is well aware of the international potential of power-to-gas and with the vast potential storage available in the German gas grid this is an area its German subsidiary ITM Power GmbH will be pursuing. The company said it had already received significant interest from gas companies at the show.
The current global drive for moving away from fossil fuels and nuclear power is a product of a multitude of reasons but ends in one outcome: an increasing presence of, and reliance on, renewable energy sources such as wind, solar, and tidal energy. Such energies have great green credentials but are variable in output, an intrinsic quality of an energy source reliant on the sporadic nature of the elements. Power-to-gas is an efficient and promising way of levelising output from renewables into electrical grids that may not otherwise be able to handle such variability. As such we expect to see many more developments in this area in the coming months.
Tomorrow we will be seeing friends old and new exhibiting on the fair floor; updates will be available throughout the day on our liveblog. Guten abend! Jonny and Marge.