Energy storage comes in all shapes and sizes. Condensers are convenient for peak storage, but they are exhausted within a few seconds. The same applies to flywheels. Water storage in reservoir lakes and pressurised gas storage in underground reservoirs can provide a buffer of several hours of energy use. Batteries and accumulators can even store energy for weeks. According to Professor of Energy Technology Bendiks Jan Boersma (Faculty of 3mE), however, chemistry is needed in order to store larger quantities of energy for longer periods ‘In the future, we will generate large amounts of inexpensive wind and solar energy, but fluctuations in production will mean energy storage is required. We will have to produce our own fuel. I think that methane is the best option, given the existing infrastructure’.
Electricity can be used to generate hydrogen, which can be combined with CO2 to produce methane, which must be diluted with nitrogen to make it compatible with the natural gas in the Netherlands. ‘The processes are known. The problem now is to use them efficiently and for large quantities’, observes Boersma. The production of synthetic gas is a good solution, as long as fossil fuels with CO2 emissions can also be used. ‘Although carbon dioxide is currently a social problem, the concentration is so low that we can’t extract it from the atmosphere’. We could thus face a shortage of CO2. Who would have ever thought that would happen?