Water demand in a hydrogen economy

In the decades ahead sustainable energy sources will gradually account for an increasing share of our energy supply, with fossil fuels fading in importance According to Van Wijk (2015), the underlying principles in this transformation are:

• All-electric: in both industry and homes.
• Locality: use of locally-available energy sources.
• Storage: under surplus supply (off-peak) conditions, provision of appropriate means for (temporary) energy storage.
• Conversion: if storage is not possible, conversion of the energy into another form for use in another way or at a later time.

The long-term ambition is to depend solely on renewable sources (solar, wind, tidal, hydropower, etc.) for the generation of energy. This will imply a need for the possible storage of the surplus electricity. In this context, hydrogen is expected to play a crucial role in the future as an energy carrier. The idea is captured succinctly in the term ‘hydrogen economy’. The concept of a hydrogen economy was developed over the last decades (Rifkin, 2004), and looks like it will be realised in practice in the decades ahead. The first hydrogen cars, with associated facilities, are already on the market, for instance in California, South-Korea, Japan, Denmark, the UK and Germany. In Germany one can already refuel at 1,650 locations, and more than 350 hydrogen stations are planned, so that motorists will be able to refuel every 90 km on the Autobahnen.

One ‘side effect’ of the hydrogen economy is the substantial level of water consumption it involves. Apart from cooling needs, every kilogram of hydrogen stoichiometrically involves 9 kg of water, both in the electrolysis (consumption of water) and in the fuel cell  (production of water). In short, the hydrogen economy is characterised by the crucial role played in it by water, with a widely varying scale of use and with an extensive branching of applications. This means that KWR can make a very meaningful contribution to the development of the hydrogen economy. The development is clearly also relevant for the drinking water sector. It is quite conceivable that drinking water companies will be playing a role of their own in the hydrogen economy.

This study examines how great the impact of a hydrogen economy would be on (local) water demand and the possible role of drinking water companies.

Source: V. Oldenbroek, A.J.M. van Wijk and L.A. Verhoef. Balancing national electricity and transport system with Fuel Cell Cars and Hydrogen. 21st World Hydrogen Energy Conference 2016. Zaragoza, June 2016.