HOW HYDROGEN STORAGE WILL MAXIMIZE RENEWABLE ENERGY PRODUCTION. BY EMMANOUIL KAKARAS
Hydrogen has two key roles to play as the world seeks to achieve net-zero CO2 emissions by 2050: enabling greater use of renewable electricity; and decarbonizing every part of the global economy. Recently, governments have thrown their weight behind hydrogen. Last year, the European Commission announced its vision to target 40GW of electrolyzer capacity by 2030 supported by up to €470 billion of investment by 2050. The UK government announced plans to invest up to £500m in hydrogen initiatives, aiming for five gigawatts (GW) of low carbon hydrogen production by 2030. Alongside this, international partnerships are being formed: for instance, Germany has teamed up with Australia for a joint feasibility study around the hydrogen supply chain and with countries in northern Africa for hydrogen production, while Portugal and the Netherlands recently signed a memorandum of understanding on jointly advancing the development of ‘green’ hydrogen.
A symbiotic relationship between hydrogen and renewables is developing. As wind turbines and solar PV panels become cheaper, so does the cost of producing ‘green’ hydrogen from renewables through electrolysis. At the same time, as renewables begin to account for a high proportion of the energy mix, their variability poses a challenge. This means the need for large-scale energy storage to smooth out differences between supply and demand becomes more pressing. Hydrogen offers the potential for energy storage on a much greater scale than the battery solutions currently being used to provide flexibility to the grids. This is a particular advantage when there are large seasonal variations in the level of electricity generated by renewables and can help capture energy that might otherwise be wasted.
Another element required to enable large-scale storage and the increasing use of hydrogen in different industrial sectors will be the set-up and conversion of large-scale infrastructure (such as pipelines or caverns) to interconnect clusters of production with end users. Such schemes, like the ones being planned in Germany and the Netherlands, will also allow longer-term storage. Separately, intercontinental trade of green hydrogen will require intermediate forms like liquid ammonia to make transportation feasible and economic.
For example, hydrogen storage could be used to capture the excess electricity generated by offshore wind farms during the North Sea’s fierce winter winds, or it could take advantage of the longer summer days and additional electricity generated by solar PV farms in regions of the U.S. Mitsubishi Power, part of MHI Group, is taking part in developing the world’s largest renewable energy storage facility: the Advanced Clean Energy Storage project in Utah, US, which seeks to produce renewable hydrogen from solar power, later used for power generation using Mitsubishi Power’s hydrogen turbines.
The Hydrogen Council estimates that by 2030, 250 to 300 terawatt hours (TWh) of surplus renewable electricity could be stored in the form of hydrogen – that’s more than the entire annual amount of electricity generated by many major advanced economies, including Australia and Italy. In addition to this theoretical storage potential, independent research commissioned by the Japanese government shows that projected demand for ‘green’ hydrogen as a fuel, rather than just as a form of storage, could require up to 16TWh of renewable power generation by 2050.
As the Mitsubishi Power project in Utah highlights, using hydrogen as an effective form of renewable power storage relies on the ability to convert the gas back into electricity. This requires power plants capable of using hydrogen fuel and generating a steady supply of electricity. As well as realizing the stored hydrogen’s potential, these plants could help stabilize grids where there are high proportions of variable renewables in the system. The Hydrogen Council claims that more than 200TWh could be generated from hydrogen in large power plants.
It is clear that hydrogen can complement renewables and is a viable partner to batteries for large-scale seasonal energy storage, helping to maximize renewable energy production. But what is more, hydrogen will help to decarbonize those parts of the economy that renewables just cannot reach, particularly the hard-to-abate sectors. In Linz, Austria, a 6MW electrolyzer – one of the world’s largest – is operating at a site owned by steel manufacturer, voestalpine. Primetals Technologies, part of Mitsubishi Heavy Industries Group, is working with voestalpine to develop a process for replacing fossil fuels with hydrogen in steel production.
In combination with renewable energy, hydrogen is the most effective carbon-free fuel to replace or supplement fossil fuels. This is because in the field where fossil fuels are currently used, there is a high possibility that they can gradually be converted to carbon-free fuels while utilizing the equipment and systems used. The expansion of these applications will greatly expand the size of the hydrogen market, making a carbon-neutral society a reality.
MITSUBISHI POWER EUROPE
Emmanouil Kakaras is Senior Vice President and Head of Innovation & New Products at Mitsubishi Power Europe. Mitsubishi Heavy Industries, Ltd. (MHI), headquartered in Tokyo, is one of the world’s leading industrial firms with 80,000 group employees and annual consolidated revenues of around $38 billion. MHI delivers innovative and integrated solutions across a wide range of industries from commercial aviation and transportation to power plants and gas turbines, and from machinery and infrastructure to integrated defense and space systems.