Written Evidence Submitted by Greenpeace
(HNZ0063)
Greenpeace is an international environmental organization with a longstanding interest in a clean energy system, publishing analyses and evidence for at least 3 decades
For a zero carbon economy, zero carbon hydrogen will be essential.
Greenpeace believes this needs to be green hydrogen from electrolysis from renewable electricity. Blue hydrogen is not zero carbon because of emissions both from the capture process - which can be expected to be around 90% efficient - and from fugitive emissions from gas extraction. There may be means of getting the higher than 90% capture but the technology and costs of delivery are far from certain. As Energy Systems Catapult say
“Without speculative innovation measures, methane reforming at a 95% capture rate is too high carbon to meet net-zero.”
Using hydrogen
What should hydrogen be used for? It should be prioritised for uses where there are no alternatives because supply of truly clean hydrogen is likely to be limited. Hydrogen has serious limitations in many applications, and quoting from Bloomberg’s Michael Liebreich:
“as an energy storage medium, it has only a 50% round-trip efficiency – far worse than batteries. As a source of work, fuel cells, turbines and engines are only 60% efficient – far worse than electric motors – and far more complex. As a source of heat, hydrogen costs four times as much as natural gas. As a way of transporting energy, hydrogen pipelines cost three times as much as power lines, and ships and trucks are even worse.
“What this means is that hydrogen’s role in the final energy mix of a future net-zero emissions world will be to do things that cannot be done more simply, cheaply and efficiently by the direct use of clean electricity and batteries”
This is reinforced by CCC analysis in their 6th carbon budget report (p146), showing why hydrogen production - which is used for the 2 applications on the right of this diagram - is not the best use of clean power if it can be used in other ways (although clearly better than curtailment)
Thus we should only use hydrogen where it is near-impossible to reduce demand or use electricity directly. As a leading analyst at CCC has put it:
“In our view, you should be looking to electrify wherever you can. Where that’s prohibitively expensive, or where it’s not feasible, that’s the role that you’re looking for hydrogen.”
The main uses for which hydrogen has been identified as having a potentially viable role are:
● for industrial processes needing high temperature heat like chemicals or glass
● Industrial processes which need hydrogen as part of the chemical process like in steel or fertiliser (and some chemicals)
● power system management esp long-term storage
● more speculative tech (though theoretically possible) like producing synthetic fuel for ships or planes with no net CO2 emissions
● Heavy transport like trains or HGVs
● Building heat
The CCC have estimated that using fossil gas plus CCS for home heating only reduced CO2 emissions by 60-85% compared to a gas boiler, presumably meaning additional land would need to be used for tree planting or nature to compensate for those emissions. Greenpeace does not see this as a good use of land compared to absorption of emissions for which there are currently no good alternative options e.g. food production.
Our own estimate of hydrogen use needed just for heating homes would equate to 120GW of dedicated offshore wind to produce sufficient green hydrogen - direct use of that electricity via heat pumps would be much more efficient. Hydrogen should not be prioritized for building heat.
The EU Energy Cities network has actually put together a hierarchy of uses for hydrogen which seems a good starting point.
Costs of different options
Although the International Energy Agency say, “the relative costs of producing hydrogen from different sources in different regions, and how they will compete in the future, are unclear”, Bloomberg’s (Michael Liebreich) project that “ ‘green’ hydrogen will be cost-competitive with ‘blue’ hydrogen in around a decade and competitive with ‘gray’ hydrogen by 2050”.
Liebreich estimates that batteries will be more cost effective for applications in ALL transport, and for all building heat. Meaning that hydrogen is more limited in being the cost-effective supply option for high temperature industrial heat, grid balancing and aviation and shipping fuel.
In conclusion, it is important that:
- government does not lock in high cost options which suit industrial lobbies like the gas industry, but which would be sub optimal from an emissions perspective.
- government appreciates that, whilst green hydrogen is vital, it will not be available in infinite quantities and is not a panacea for all the delivery challenges and investments that need to be made across buildings, transport and industry