Dave Elliott: The National Infrastructure Commission (NIC), the UK government’s advisory body, recently said that the government “should not agree support for more than one nuclear power station beyond Hinkley Point C before 2025”, since renewables were getting cheaper and could prove a safer investment. See my earlier post. The NIC’s view was backed up by a study by the Aurora consultancy. Aurora looks at the implications for power sector decarbonization of two different approaches to reducing emissions in the heat sector – electrification and hydrogen /greener gas, though its green gas comes mostly from fossil sources, with CCS. It concludes that a green gas/hydrogen heating route would need a 30% increase in 2050 power generation, whereas an electrification approach, with heat pumps being used, would require a 67% increase in power generation, as well as grid reinforcement. It notes that “Hydrogen-based heating puts less strain on the electricity system.” A similar conclusion emerges from another study of green heat options and costs done for the NIC, by Element Energy and E4Tech, in even more detail. It says it is still tentative, but the “hydrogen-led heat decarbonisation pathway could be lower in cost by several tens of billion pounds than an electrification-led or hybrid gas-electric”. But, like Auroa, the study sticks to the fossil CCS route to hydrogen – it sees P2G as too expensive. Interestingly though, while both this study and Aurora’s conclude tentatively that the hydrogen route may the cheapest, as I’ve noted before, Imperial College London has produced a report for the Committee on Climate Change (CCC) looking at hydrogen gas grids and domestic electric heat pumps, which says a hybrid mix may be the least-cost option, with the “hydrogen alone” route being the most costly. And, like the NIC, it seems to ignore heat grids. Looking so far ahead is fraught with difficulties, so specific technology choices for specific end-uses will be hard to make, but some sort of consensus seems to have emerged on the wider picture: if we want to go that way, renewables can supply the bulk of our power by 2050, and also heat and transport fuel, as demonstrated by National Grid’s new Community Renewables scenario. In that, wind and solar dominate power supply (75% by 2030!) and it uses hydrogen for some heat and transport, and also some hybrid electric-gas heat pumps/boilers for heat. Biomass use is limited mostly to power, with a few local heat networks, while there is under 6 GW of nuclear. Fascinating stuff – a mostly non-fossil future. But perhaps not something most oil companies would recognize; see my next (much delayed/held over) post.
Physics World 8th Aug 2018 read more »