Set up in 2007, the Energy Technologies Institute (ETI) brings together researchers at Loughborough, Nottingham and Birmingham universities and elsewhere to look at system-level energy issues in a £400m UK industry–government partnership. That scheme finishes at the end of this year.
So, although we will no doubt hear more from the ETI in its last year, and from the various Catapult groups that have emerged, the Institute has brought together some of its conclusions into something of an early “goodbye” overview of the various options. The report is based on the ETI’s Clockwork and Patchwork scenarios, now revised since their original publication three years ago, for example taking account of the downward trends in energy service demand, which the ETI says “tend to make carbon targets easier to meet”.
The high-level conclusion is that “a balanced, multi-vector approach can deliver an affordable, low carbon UK energy transition, with costs rising to around 1% of GDP by 2050”. But it says “without certain key technologies, meeting carbon targets would be much harder, jeopardizing industry and severely limiting lifestyle choices”. Although it warns that, given the potential for innovation across a range of technologies, “we cannot be prescriptive about the precise mix over a 30-year period”, it does push some ideas forward, and adopts quite a challenging approach.
Hydrogen: the word from the UK’s Committee on Climate Change
For example, the ETI notes that “sustainably grown biomass has the potential to become a critical resource for the UK energy system”, since it can be burned directly for heat and power, or converted into low-carbon gases and liquid fuels to decarbonize hard-to-treat sectors. That’s not a popular view, given the land-use constraints and biodiversity issues. It’s more usual these days to look to farm, food and municipal bio-wastes as a bio-energy source. The ETI also says that “carbon capture and storage (CCS) offers a versatile solution with applications across power, industry and hydrogen production”, arguing that “without CCS, UK carbon abatement costs could be double by 2050”. Given the low state of CCS work at present that’s also provocative.
However, the ETI overview’s major theme is that “bioenergy and CCS are especially valuable in combination”. It says that, “together, they offer the potential for negative emissions to counterbalance the continued use of fossil fuels in difficult sectors like aviation. Without negative emissions generated in the UK, achieving a ‘net zero’ emissions target will require the prohibition of certain industrial activities and lifestyle choices or reliance on imported carbon credits from other countries.” So, like the IPCC, the ETI backs BECCS. But with CCS at a low ebb, that seems optimistic.
ETI seems to be on safer ground when it says “system flexibility requirements will change, and new approaches will be needed. Storage of electricity, heat and gas (including hydrogen) will all have a role to play, along with backup generation in power and hybrid systems for heat”, although the institute’s approach to green heat is quite challenging. “Low carbon heat solutions exist but consumer experience is key,” it says. “Most UK households have relied on gas boilers for more than a generation. Low carbon alternatives will require powerful consumer propositions that match, if not exceed, current experiences”. That could be taken as a challenge to the government’s initial focus on fossil gas decarbonization via electric domestic heat pumps, although in the ETI’s Clockwork 2050 scenario, heat pumps make up 20% of all building heating capacity, and supply over 50% of UK space & heat production. So the “electrification” approach is still in there.
Heat time
However, the ETI also backs heat networks. In its Clockwork scenario, large district heat networks are also rolled out from 2030 onwards in urban areas, with a range of technologies deployed to supply the heat to these networks, beginning with smaller gas combined heat and power (CHP) plants, while medium-term, low-carbon sources include heat recovery from large-scale thermal electricity plants. But, more dubiously, it says “in the longer term, new and extended networks are fed by heat offtake from small modular CHP nuclear reactors”. Though the institute also adds “commercial-scale marine heat pumps also make a sizable contribution by 2050”.
The ETI continues “in those areas where heat networks are not economic, there is a recognition that full electrification — to the extent required to cope with extreme cold weather — would place undue stress on electricity networks. For this reason, existing gas networks in these areas are maintained but energy throughput is much reduced, with gas boilers now playing a supplementary role in support of electric heat pumps, as part of a hybrid solution.” That is very much the CCC’s line, heat pumps backed up by gas boilers, some of the latter running on hydrogen.
So ETI says “some areas undergo conversion of the gas distribution network to deliver hydrogen to buildings. In areas anticipating hydrogen conversion, advanced notice ensures end-of-life gas boilers are replaced with hydrogen-ready models, minimizing the risk of stranded assets”. It adds “thanks to a concerted effort by government and gas network operators, around one third of the remaining gas network in 2050 is fully converted to hydrogen distribution, delivering over 55 TWh of hydrogen annually. The other two-thirds of the remaining distribution network continue to supply natural gas, but reduced gas boiler operation means that annual delivered energy is actually lower than from hydrogen”.
Finally, in addition to industrial take-up of green energy and hydrogen, the ETI says electrification of transport can begin to deliver significant carbon dioxide cuts from 2020 onwards. The speed of transition is uncertain, but it says whole-system coordination can ensure we make best use of existing electricity system capacity, minimizing the need for investment in grid upgrades to support mass electric vehicle (EV) adoption. Well, we’ll see.
Growth patchwork
In the ETI’s Patchwork scenario, in which growth and wealth are at higher levels, there is much less government co-ordination, slower decarbonization, but more diversity. Less CCS, hydrogen, and nuclear, but more CHP and local photovoltaics (PV), with electric heating and heat storage being popular. Lots to debate about that! And, indeed, about the whole ETI approach. Its acceptance of renewables as major players is welcome and its commitment to hydrogen is interesting, but its promotion of nuclear and CCS, including BECCS, seems a little surprising. More understandable is its hedging of bets on green heat – the “pipes versus wires” debate continues!
The ETI concludes by saying “we have refreshed Clockwork and Patchwork as part of the ETI’s legacy of insights and evidence. The scenario team now takes this work forward within the Energy Systems Catapult. We hope that this publication will once again stimulate discussion with stakeholders across the energy system as we continue to learn together about the key options and choices facing decision-makers across the UK”. Amen to that.
