Energy can take four (4) forms:
- Liquid, one of the most known such as petrol, used daily in homes, cars and in the power sector
- Solid, such as coal which has powered the industrial revolution up until now
- Gaseous, such as natural gas, best known for heating homes
Electricity is not storable
The first three forms are easily storable energy. Petrol in your tank, coal and natural gas under the earth’s crust. The only form of energy that is difficult to store is electricity. Once you produce electricity from power plants or renewable energy sources, it must be consumed. The so-called supply meets demand paradigm. Today, however, the European Union is betting on an energy transition from fossil fuels (i.e.: stored energy) to renewable energy sources such as electricity from wind and solar. The issue is that renewable power generation is characterised by variability and intermittency (the sun does not always shine, and the wind does not always blow).
The need to store electricity in other energy forms increases
Yes, progress is being made in terms of increasing the reliability of wind data in advance so as for the maximum of power to be generated but as the renewables’ penetration increases, the problem of balancing supply and demand for operators of electricity networks also rises. Periods of non-consumption-oriented production of renewable energy are usually managed by curtailing renewable power sources because the electricity cannot be sold at the time of generation. the solution is therefore to develop storage. There are many different storage technologies such pump hydro, batteries, flywheels and hydrogen. Each have their own specific characteristics and capabilities to help balancing the power grid when there is too much or not enough renewable electricity generation. Below is a demonstration of such excess electricity in the summer months and the deficit in the winter in Germany in 2050:
Source: Hydrogen Council
Hydrogen through electrolysis can convert excess electricity into hydrogen during times of oversupply. The produced hydrogen can be stored over short and long times and in large quantities in underground caverns, natural gas grid, and in hydrogen refuelling stations (HRS) tanks where the electricity stored and hydrogen consumption for re-powering and other applications is therefore decoupled and more renewable energy can be produced and integrated into the power system.
Source: Hydrogen Council
The electrification-only pathway is not the silver bullet
However, more renewable energy is foreseen in other economic sectors (transport, heating & cooling, energy intensive industries, etc.). Some advocate for the electrification of transport through Battery Electric Vehicles (BEVs), others for the electrification of heating and cooling both at home and in industry. Finally, some indicate that the electrification of the entire European economy through renewable energy is the only way forward. These “electricity-only” proponent disregard completely the need for a second energy carrier such as hydrogen.
The role of hydrogen
The ability of Power-to-Hydrogen to access and integrate each sector of the energy system opens the opportunity for deploying and utilising renewables to a much greater extent as a cross-sectoral electricity-only focus will be difficult, costlier and put even more stress on the electricity grid. Hydrogen has the capacity to decarbonise liquid and gaseous sectors on top of the power sector.
Therefore, the Commission’s proposal to integrate more renewable energy in the other economic sectors such as in transport via the use of, inter-alia, Renewable gaseous and liquid fuels of non-biological origin (i.e.: hydrogen) and carbon-based streams is welcomed. However, limiting the possibility for hydrogen and hydrogen-based fuels to either a direct connection or measuring it via the EU’s average GHG intensity for only new plants is not enabling the potential that these fuels have in decarbonising the transport sector whilst increasing the share of renewable energy in the economy.
Thus, the possibility for these fuels to be recognised using different pathways is necessary and should be acknowledged. Such pathways could be through renewable power purchase agreements between renewable energy producer and an electrolyser / customer, through the use of guarantees of origin and through renewable electricity obtained in accordance with balancing needs in times of surplus energy associated to a time link (i.e.: when the “excess” electricity would have been otherwise curtailed/lost). These should be fully counted as renewable energy as it integrates more renewable energy in the various sectors as well as for various actors: hydrogen as a zero-emission fuel for vehicles (e.g.: cars, trucks, trains, ships), hydrogen as a raw material for low carbon industry (e.g.: steel production) and hydrogen as a low carbon energy carrier (e.g.: heating gas in homes).