Utility Week

22 | 26TH OCTOBER - 1ST NOVEMBER 2018 | UTILITY WEEK Operations & Assets Analysis T he UK is doing a lot on decarbonisa- tion. For one thing, the country has a target to reduce emissions by 57 per cent by 2030 against a European Union goal of 40 per cent. It is committed to an even more ambitious 80 per cent reduction by 2050. However, most decarbonisation up to this point has concentrated on the relatively "low-hanging fruit" of electricity generation. Very little progress has been made on the decarbonisation of heat. The plan – for better or worse – was to decarbonise electricity and then elec- trify heat, as well as other sectors such as transport. However, it may not be that sim- ple. At approximately 300GW, aggregate peak demand for heat is roughly five times greater than that for electricity, according to Ofgem. Currently, 80 per cent of UK homes are heated by gas, with heat accounting for around one-third of UK CO2 emissions. "The volatility of heat demand is enor- mous and extremely difficult to deal with," says Malcolm Keay, a senior research fellow from the Oxford Institute for Energy Studies. "There is no real alternative at the moment to fossil fuels for seasonal storage. The easi- est way to do it is by great big piles of coal – that's not acceptable any more, we have to move on to something else." Speaking at the Low Carbon Networks and Innovation conference – held in Telford by the Energy Networks Association – Keay argued that hydrogen is key to the decar- bonisation of heat. However, he warns, from a political perspective it is the "wrong sort of technology". Renewable heat Alternatives are few and far between. "Energy efficiency is certainly going to be an option in terms of the decarbonisation of heat, but there is still a question about whether it can deliver on the scale required – an 80 per cent reduction or 100 per cent reduction," says Keay. "Renewable heat brings big environ- mental and economic problems. If anything, there are moves at the moment to reduce the amount of renewable heat in the UK because of the impact of wood burning. "District heating is, frankly, pretty expen- sive, and it's not really clear if it's compat- ible with the move towards energy efficiency because there is so much capital cost involved – if heat demand is lower, the result will be a higher cost for the individual users of heat. "Heat pumps have been mentioned as a large part of the solution, but frankly they've been pushed for a long time and have not proved very successful in consumer terms or in economic terms. I think it's rather optimis- tic to see them as a part of the solution." "Hydrogen could, in principle, form part of a sustainable energy economy," he says, adding that the fuel could complement intermittent renewables, it could be used in transport – it is the current frontrunner for freight transport – and it could be used in fuel cells. "If that were the case, you might conceivably be able to achieve whole-system co-ordination more easily, by using home fuel cells to provide heat and generate elec- tricity," he says. The existing gas pipeline system is, to a large extent, already compatible with hydro- gen, because the distribution mains are in the process of being converted to polyeth- ylene. What's more, the consumer impact would be "relatively manageable", compared with other options. "People could use basi- cally the same equipment. They might have to replace the burners in that equipment in the way they did when the UK moved over from town gas to North Sea gas." Keay asks whether heat decarbonisation – which is inevitably going to affect gas – can be managed more smoothly. One of the main points is that decarbonising heat via electric- ity is pretty difficult. He says: "I'd argue that the main alternatives would also present problems. One of the frontrunners at the moment – and I agree it's not the only one – is using hydrogen from methane reforming." But is a hydrogen solution deliverable? Bad politics Keay believes that politically the argument for hydrogen "doesn't work". "I'm afraid the policy challenge is far and away the biggest one, and that's what has to be looked at. It's not enough to look at the pure economics and the technical aspects of it if a solution will not work politically." He adds: "From a political perspective, it's the wrong sort of technology, it's got the wrong sort of economics and it's the wrong sort of policy. What it's competing with – unless the government intervenes and forces consumers to change – is gas. And there's a huge gap [in cost]." The Oxford Institute for Energy Stud- ies carried out research looking at the ways in which the "green gas" option might be taken forward in order to emerge as a "fully- realised policy option". The group suggests it could only be delivered on the basis of a "major strategic decision by the govern- ment" and a "clear vision of the future low- carbon energy system". "What's happened in the electricity industry has basically turned the whole Hydrogen left in mid-air Heat is a hot topic in the energy sector. But there are fears that a lack of political will is blocking one of the most likely paths to this decarbonisation – hydrogen. Lois Vallely investigates. ANNUAL ADDITIONAL COSTS (£) VERSUS CONSUMPTION (MWH) Hydrogen District heating high Heat pump District heating low Direct electric Storage heating Source: NEA £800 £700 £600 £500 £400 £300 £200 £100 £0 5MWh 10MWh 15MWh 20MWh

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