Similarly, UK politicians must recognise that our geographic location, climate and weather patterns are major determinants of future energy policy and that they can try but will fail to alter them. The energy trilemma, a phrase that rightly suggests the difficulty in balancing the competing demands of affordability, reliability and sustainability, should be set against the UK’s particular energy needs.
As a result of natural gas abundance, the UK has the world’s leading gas grid infrastructure in place, directly supplying the energy to heat 85 per cent of UK homes. It would be a travesty not to use this existing infrastructure as part of the solution to the trilemma, and “green” gas could be the key.
Heat demand is seasonal – no surprise there – but its peaks during the winter either need to be met by supply or people will go cold, and no politician wants that. Switching away from gas heating will mean households face considerable up-front costs, which are simply unaffordable. A recent study of Bridgend, produced by Wales & West Utilities, suggests that 81 per cent of households simply do not have the cash at their disposal to make that investment without massive subsidies.
There is no definition of what “green” gas is. Indeed, this is part of the attraction, in that there is no winner or silver bullet but instead a range of green gases. Perhaps “low carbon” gas is a better description. First off the blocks is biomethane. This is the gas captured from waste processing, typically anaerobic digestion. The technology is proven, it has worked for years. Companies like Severn Trent clean up the biomethane from their Minworth sewage treatment works and inject the green gas into the grid.
BioSNG is next, a green gas that achieves its status because it uses waste materials, usually sent to landfill or incineration, to create the gas.
The process is technically complex, involving advanced plasma technology. Ofgem has recently awarded National Grid funding to develop a commercial scale plant in Swindon, having seen the success of smaller trials of the technology. The alternative use of waste gives the gas its green credentials. The Swindon plant envisages supplying gas for heavy goods vehicles but there is nothing to stop it being fed into the gas grid for everyday use once it is blended to reach the gas quality standards required.
Another green gas is hydrogen, currently produced from natural gas using steam methane reforming, where the carbon can then be captured. The question is how much hydrogen can be used and in what manner? It is possible, within existing gas quality guidelines, to mix up to 2 per cent of hydrogen into the blend that flows through the gas grid. Some studies suggest that up to 20 per cent might be feasible – remember this makes the overall mix of gas greener.
However, Northern Gas Networks is conducting a feasibility study into 100 per cent hydrogen through the gas grid. Its Leeds 21 study is arousing considerable interest within the industry on the basis that it envisages using the existing gas grid and conventional heating systems such as central heating in the home, but in a completely carbon-free way.
This article is not designed to reach the conclusion that one single option can solve the UK’s energy trilemma. There is no silver bullet.
However, green gas, whatever the source, offers a viable way forward using our existing gas infrastructure. It means not turning our back on gas but embracing it. Overall, it could prove to be the most cost-effective way of keeping people warm and meeting our international climate change obligations.