Power-to-Gas is a technology that converts energy, mainly electricity, into hydrogen and oxygen through electrolysis and then into methane through a chemical reaction called methanation. The resulting product is a type of synthetic natural gas or substitute natural gas (SNG), also known as e-gas. It shares the same properties as natural gas and can be used, stored and transported exactly like the latter. The process functions as an efficient energy storage system. If the electrolysis is powered by
renewable energy and the methanation uses carbon capture, the resulting gas is a carbon-neutral energy source.
Why does renewable energy require storage systems?
For a reliable energy network and permanent security of supply, the availability of and demand for power must constantly be in equilibrium. In reality, this doesn’t just happen automatically. Production has to be ramped up when demand outweighs supply. Unfortunately, renewable power largely relies on natural factors that can’t be controlled as easily as fossil-fuel based sources. Photovoltaic power is generated by solar radiation during the day, wind power only when it’s windy, hydropower when there is enough water. Geothermal power is the only form of renewable energy that is completely immune to fluctuations. Currently, non-renewable energy kicks in when no renewable power is available, while surplus green energy goes to waste when supply exceeds demand. To achieve a fully renewable energy supply, storage systems have to bridge the gap at times when natural energy availability is low, but demand is high.
Is Power-to-Gas the future of grid energy storage?
The energy storage of the future has to fulfil several requirements: Its energy efficiency should be as high as possible, and the required resources should be minimal, renewable and non-toxic. Including initial investment (both financial and in terms of resources used and emissions generated), the entire environmental impact should be as small as possible. Tried-and-tested forms of energy storage that meet some of the main requirements include thermal (heat stored in air, water or stone), mechanical (such as compressed air, hydroelectric and pumped energy storage) and kinetic (flywheel or gravitational storage). Power-to-Gas offers two advantages over these methods. The methanation process can employ carbon capture and the resulting gas can be fed directly into the natural gas grid, where energy is transported with less energy loss than through the power grid.
Effectively managing surplus energy
MAN Energy Solutions provides technologies to solve various challenges of the energy transition. To successfully combat global warming, these solutions must all go hand in hand. Hydrocarbon-based energy, which is still indispensable, must become cleaner, its utilization needs to be more efficient and the resulting emissions have to be reduced. At the same time, as renewable energy production is ramped up, it has to be saved, distributed and managed, as well as supplemented when needed. Energy storage is one part of the sustainable energy puzzle.
For the first time ever, the international community has set a climate target. We want to play our part in helping to achieve it.
Power-to-X carbon neutral energy storage
MAN Energy Solutions sees enormous potential in Power-to-X technology. It can be used to convert renewable energy into synthetic fuels such as synthetic natural gas. The company is offering a 50 MW complete solution on an industrial scale which could supply 19,800 natural gas-powered cars, each driving 15,000 kilometers annually. Marc Grünewald, Head of Business Development, Power and New Energies, explains the benefits to all, and especially the environment: “With the help of Power-to-X, climate-neutral synthetic gas can be produced which reduces the carbon footprint in a wide range of applications without the need for major infrastructural investment.”
Cutting-edge energy storage in a modern Power-to-Gas plant
German automotive industry giant Audi is pioneering a cutting-edge energy storage technology – with help from MAN Energy Solutions who delivered the methanation reactor. The Power-to-Gas reactor combines three building blocks of a successful energy transition. It harnesses surplus renewable energy, thus preventing waste and storing it in a different shape, making it available for use in sectors other than electricity.