One of the main biases in international mitigation strategies is related to what I believe is a wrong perception of the role of electrons versus molecules in our energy system. Currently, some 80% of energy delivered worldwide to end-users is by way of molecules (mainly oils, gases and biomass) and only around 20% through electrons (power). Yet, most of the subsidies and innovation to make the system greener is focused on electrons (renewable power production), while the replacement of grey by green energy in the ‘world of energy molecules’ is proceeding much slower (mainly the slowly progressing green fuels/gases and co-firing).
Some stakeholders and policy makers believe that this issue will be solved automatically, because we are moving towards an all-electric world, but this is probably a huge mistake. Even if the complete energy system were green, then still a substantial part of it will be based on (green) molecules, because: many industries need molecules to produce physical goods; storing and transporting electrons are and will remain at least 10 times more expensive than storing and transporting molecules; intensive heavy transport systems can probably not economically be serviced by electrons only.
That is why power-to-gas (P2G), i.e., converting renewable electrons into green energy molecules in whatever form, seems an indispensable technology option for realising a more equal greening process between electrons and molecules. This leads us to a second bias in our mitigation strategies. While literally billions of euros are spent per year on subsidies to produce green electrons (in the EU alone already some €50 billion per year), close to zero subsidies are available for converting these electrons into the sometimes optimal form with, e.g., P2G technologies. It is difficult to understand this, but it anyhow contributes to the difference of speed in which electrons versus molecules are greened.
Another bias that is difficult to understand in this respect is related to the prime P2G output: green hydrogen. Currently, some 140 million tonnes of hydrogen are produced worldwide via steam conversion, mainly for fertilizer and other chemical production. Compared to this, the production of green hydrogen still is negligible. The CO2 footprint of hydrogen production is enormous, because 1 tonne of grey hydrogen produced with conventional technologies results in 10 times more tonnes of CO2 emissions! Consequently, worldwide hydrogen production is responsible for 1.4 gigatonnes CO2 emissions, or roughly 10% of the ‘Paris-gap’ (about 12 Gt) for reaching the 2oC target. Why does the world accept this, if converting renewable energy surpluses into green hydrogen is such an obvious component of a low-emission energy transition?
Catrinus J. Jepma's Blog - Uploaded on 04/11/2016
Professor Energy and Sustainability at the University of Groningen
Chair of JIN Climate and Sustainability
* The viewpoints expressed are those of the authors.