Mar 2023
by Institution of Gas Engineers and Managers

IGEM's response to the CCC report: Delivering a reliable decarbonised power system

IGEM warmly welcomes the new report from the Climate Change Committee which provides a series of recommendations for delivering a reliable, secure and decarbonised power system by 2035.
Much of the flexibility provided to the electricity system today comes from gas-fired generation. Increasing renewable generation and a gradual decline in electricity demand has reduced the annual share of generation from gas from 46% in 2010 to 40% in 2021. However, our reliance on gas generation capacity has increased, with the range of generation coming from gas having widened to 7-70% of the generation mix at any one time.
The CCC’s report reiterates that a reliable, resilient and affordable decarbonised power system is central to securely achieving Net Zero in the UK with reduced dependence on imported fossil fuels. The three key commitments this report asks from Government are:

  • New low-carbon back-up generation, with hydrogen-based power stations and some continued use of fossil gas, made low-carbon through use of carbon capture and storage.
  • Smart shifting of consumer demand, to help to smooth peaks in demand and absorb excess supply, especially through controlled timing of electric vehicle charging and use of heat pumps.
  • New storage solutions, beyond simply the use of batteries. Most critical is the use of surplus generation to produce hydrogen through electrolysis (‘green hydrogen’), providing long-term storage so it can later be used to generate electricity. 

It is positive to see the modelling having sought to capture the system dynamics of hourly supply and demand balancing, including increasing demand, extended periods of wind drought and climate change impacts, such as flooding and extreme weather that above ground assets tend to be more prone to. It is surprising, however, that distributed reciprocating engines that are prevalent today appear to have not been considered, which offer economic dispatchable electricity generation at low load factors and are available as hydrogen-ready now, and also how there is a reliance on interconnectors to supply electricity at times of peak demand. 
Coming through very strongly in the report is the significant infrastructure investment and delivery that is needed for the transport and storage of electricity, hydrogen and CO2 to support a decarbonised energy system. The Climate Change Committee specifically recommend the Government must commit to a long-term cross-sectoral infrastructure strategy that identifies low-regrets hydrogen and electricity infrastructure development. This includes consideration of hydrogen infrastructure developments, such as storage and transmission that are low-regret regardless of subsequent decisions on use of hydrogen for heating buildings, and that this should be used to inform a set of low-regret hydrogen and electricity infrastructure investments that can proceed immediately. We see this as being particularly important for the acceleration of progress at industrial clusters with simultaneous build-out of hydrogen production, storage and transportation in pipelines needed to provide for industry, large scale power generation and transport hubs, as well as hydrogen blending and subsequent gas grid conversion. 
Heat pumps are well supported in the report regarding their provision of flexibility to the electricity system, and hybrid heating systems do get mentioned for support to deploy in the near term; however, it is worth noting the increased flexibility offered by heat pumps in a hybrid system help to optimise system costs and allow high value, indefinite, demand shifting across energy vectors when required, such as through the provision of aggregated fast frequency demand response. Heat pumps utilised in hybrids are compatible with all boiler types today, and equally with hydrogen and hydrogen-ready boilers when they become available on the market. 

Imperial College’s recent ‘Flexibility in Great Britain’ report identified that coordinating hydrogen production capacity and associated infrastructure effectively has significant system benefits, and that there is a need to diversify hydrogen production routes and develop CCS infrastructure at scale to deliver hydrogen cost-effectively – which both seem to be reflected in this new CCC report. Imperial’s report also showed the total system cost benefit of using hydrogen in domestic heat, compared to full-electrification, in both low (£18.8b/yr annual saving) and high flexibility (£11.7b/yr annual saving) market conditions.

The CCC make reference in their report to the need to identify areas suitable for hydrogen linked to the policy decision for the decarbonisation of home heating. With spatial analysis undertaken by Element Energy for gas networks having previously identified 42% of gas grid connected homes within industrial cluster areas, the potential for a hydrogen heating choice for consumers with stand-alone boilers or as part of hybrid heating systems in these areas is substantial. Hydrogen transmission infrastructure and further distribution network rollout of hydrogen can provide a networked supply to non-cluster areas to extend this choice – not only to homes elsewhere across other regions, but importantly to distributed industrial facilities and to flexible power generation sites that are located amongst homes up and down the country.
And with the global mission, co-led by UK Government, to ambitiously bring down the cost of green hydrogen on a customer bill to $2/kg (~4.5p/kWh) by 2030, hydrogen could be a competitive fuel for all demand sectors sooner than we may expect.