These systems are currently smaller but increasing in size and number due to their ability at accept fluctuating power input, such as is available from solar and wind, and deliver hydrogen at high purity and pressure. As it is a relatively new technology, cost reductions are expected with time and increased scale.
Other technologies are also being developed such as Anion Exchange Membrane (AEM) and Solid Oxide Electrolysis (SOE). AEM systems currently tend to be small but have the potential to be ‘racked’ together to increase output. SOE systems are high temperature (from 600 to 900°C) and if waste heat is available then this can be used to improve the energy needed for hydrogen production. These systems offer advantages in different sectors