Hydrogen is in the news regularly these days - see my last few posts. Some are quite keen on it - see the recent hydrogen champion report. Others are pretty hostile, seeing it as mostly a fossil fuel ploy. Well that certainly is where blue hydrogen comes from, with carbon capture and storage to clean it up a bit. Others think hydrogen has been oversold, including green hydrogen for heating: Michael Liebreich says ‘it will take until 2030 to rein in the current bout of hydrogen mania… cult deprogramming takes time'
The UK Climate Change Committee (CCC), an independent government advisory body, is less severe. In its new report on ‘Delivering a reliable decarbonisation system’ it sees hydrogen production, use and infrastructure as important: ‘It will be needed for hard-to-decarbonise sectors such as industry and shipping and is expected to have a role in power generation, although the scale of this remains uncertain.’ It also adds that it is likely to provide flexibility in the power sector ‘to store excess power and generate on-demand to back up variable renewables’.
However, it too offers bad news. It says that fossil-fuel derived blue hydrogen will have to be favoured up to around 2035, since there won’t be enough renewable output until then for green hydrogen production by electrolysis. So, up to 2035, ‘zero-carbon electricity must be prioritised for displacing unabated fossil generation and meeting increasing demands from electric vehicles and heat pumps.’ But after that, green hydrogen could expand and even lead. Though for now, focus on Blue. Despite the higher emissions.
It takes quite a hard line on this, a bit surprisingly given that some green hydrogen projects are underway. Some of them are for home heating, which the CCC does not favour since it is seen as much less efficient than heat pumps. But it also opposes the use of renewables to make hydrogen for other uses at this stage: ‘Due to the priority of decarbonising the power grid, green hydrogen produced from dedicated renewables projects should only be based on extra zero-carbon electricity capacity or from zero-carbon electricity sources where it is not possible to connect to the grid. Existing zero-carbon electricity capacities and commitments must not be allocated to dedicated hydrogen production’
Well maybe that makes sense, if there will not be enough spare for a while, but CCC also note that whereas ‘green hydrogen produced from a dedicated source of offshore wind has been estimated to cost around £80/MWh in 2035 falling to around £70/MWh in 2050, ..in contrast, hydrogen produced from curtailed electricity is estimated to cost £46-53/MWh in 2035 and £42-50/MWh in 2050.’ So it’s cheaper if we use surpluses rather than dedicated supply, with CCC quoting ~£50/MWh for blue hydrogen .
However, the CCC report says ‘It appears implausible that all UK hydrogen demand could be met from domestic non-fossil production by 2035, given likely limits on the rate at which renewable generation capacity can feasibly be built’. Well that’s not totally clear. We could aim for massive expansion of renewables. For example, National Grid ESO, the UK system operator, has fully decarbonised scenarios with wind at up to 115GW GW by 2035. And with PV solar added, LUTs scenario has renewables providing about two thirds of UK power supply by then.
The CCC says it has ‘not attempted to define the appropriate balance of hydrogen and gas CCS for low-carbon back-up capacity, but a mix of the two is likely to be sensible. At least until the 2040s, additional hydrogen demand at the margin might need to be met through blue hydrogen production.’ It adds ‘While the precise balance between use of hydrogen-fired turbines and fossil gas plants with CCS in the power sector remains uncertain, some use of some hydrogen to provide on-demand power to meet peaks and back-up renewables appears necessary. This is likely to lead to a very variable demand for hydrogen in the power sector, necessitating the use of hydrogen storage to ensure that the necessary hydrogen is available.’
A second report released by the CCC, entitled ‘Net Zero Power and Hydrogen Capacity Requirements for Flexibility’, written by engineering consultant Afry, confirms the view that ‘blue hydrogen is expected to remain the dominant source of hydrogen production until 2035’ in the CCC’s central scenario. But it says that green hydrogen will become dominant over blue in the years between 2035 and 2050 due to ‘a faster increase in renewable and nuclear generation as compared to electricity demand’. Even so, the main CCC report says that ‘it is unlikely that any contributions from green hydrogen imports, or electricity imports for domestic green hydrogen, would remove the need for blue hydrogen on a 2035 timescale,’ given that ‘the build rates required for the Government’s existing ambitions for zero-carbon electricity mean that further zero-carbon capacity for dedicated hydrogen production is not expected to be available at significant scale by 2035.’
Well we shall see. Certainly the government could have problems getting funding for a big renewables expansion if also it sticks with nuclear and CCS expansion. But as Hydrogen Insight’s useful coverage shows, the hydrogen debate continues, with some seeing the drive for green hydrogen as be pushed forward by booming offshore wind projects. Of course, that may take time and may not happen. Meantime though, there’s the idea of blending hydrogen with fossil gas as an interim option for the gas grid. The GMB Union back blending as a short-term way forward, with a full switch to green hydrogen presumably later. However a green lobby group led by consultants E3G, object to this: they worry that it leaves fossil fuel still in the game, perhaps helped by labelling gas boilers ‘hydrogen ready’, and that this will be more costly than heat pumps. They also challenge some of the claims about problems with heat pumps in the Hydrogen Champion report.
Views do seem to differ. That report noted that, although hydrogen for heat can’t have any meaningful role to play until after 2030, ‘scale-up could be swift beyond 2030, with heating (for both domestic and commercial purposes) potentially accounting for up to around 40% of total hydrogen demand by 2050.’ E3G says ‘this 40% claim is highly disputable, and is much higher than the Climate Change Committee’s scenarios. Recent modelling for Shell suggested that hydrogen for heating will only represent 0.4% of the total hydrogen demand. A high hydrogen for heating scenario does not represent a strategic use of a limited resource, and could detract from other sectors where hydrogen could play a vital role in meeting net zero, such as power, steel and aviation’. The debate goes on: most agree that hydrogen will play a key role, and green hydrogen is best, but for heating it’s much less clear.
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