At last, heat has made it to the front page. The Cinderella of energy decarbonisation (electricity and transport being the two ugly sisters) now seems to be being taken far more seriously. Much discussion swirls about just how far heat is lagging in decarbonisation targets, and what needs to be done about it, with some renewed emphasis on heat decarbonisation strategies by the Committee on Climate Change and (I hope) some greater urgency on reshaping the Renewable Heat Incentive so that decarbonised heat options can be supported and progressed.
But what about Cinderella’s even more neglected twin, cooling? What is being done, or should be done about cold? And, by the way, is it a problem that ought to register on the decarbonisation radar? The problem recognition dial certainly still flickers around the zero mark, but a problem it certainly is. And as the climate changes, it will register more. This is because we’re living more and more in a world characterised by cooling demand – air conditioning in offices and shops, refrigeration for transport of food and perishables, and, of course, straightforward refrigeration in homes. Pretty much all cooling is undertaken by very old technology, vapour compression refrigeration, which uses refrigerants – usually hydrofluorocarbons (themselves a potent greenhouse gas) and huge amounts of electricity and sometimes even diesel to drive the refrigerants around to do their work.
The use of this old technology is already expanding fast as evidenced by the number of refrigerated vans driving around, spilling out far higher levels of NOx and particulates from their refrigeration units than the truck itself actually does. TheDemand for these technologies is projected to expand much further.
Already, air conditioning and refrigeration account for about 20 per cent of electricity supply, and this looks set to rise sharply as the UK increasingly adopts US levels of domestic air conditioning penetration. National Grid expects the UK’s use of domestic air conditioning to rise from a few thousand units today to perhaps six million by 2040, entailing a huge rise in electricity demand, along with seasonal and daily demand spikes that will distort present patterns of electricity use.
So, quietly, many of the gains we look set to make in energy efficiency and lowering our use of electricity may be offset by our appetite for cold – an appetite that somewhat ironically is likely to grow as the world heats up.
The debate on heat has swung markedly in recent years away from the earlier assumption that heat (delivered mostly by mineral fuels) could be decarbonised by electrifying everything. Awareness of the huge daily and seasonal variation in demand and the barely conceivable amount of new electricity capacity we would need to reliably supply all heat demand by electrical means has prompted a re-think in several quarters.
This has caused many to now see decarbonising heat as a portfolio job – some green gas injection, some electricity, some efficient district heating, and perhaps a move in the longer term to a hydrogen-based gas economy. However, creeping up behind all this effort looks to be the next possible consumer of improbable levels of new electricity demand: cooling. And at present there is next to no discussion (Prof. Toby Peters and Birmingham University, I honourably exclude you from this) on whether and how it might be possible to defuse this trend, other than by telling everyone that air conditioning will be banned and perhaps we should stop refrigerating all our food to boot.
There are possible ways forward for cooling that change the paradigm of refrigerants plus electricity, and come out at a far lower carbon cost. These include changing the refrigeration motors on vehicles to cold producing engines run on liquid gas, or capturing the cold from the transport of liquefied natural gas and reusing it for domestic cooling purposes, or engineering ‘night storage’ of cold during low demand hours for use at high demand times.
But right now, in the absence of any plan on cold decarbonisation or incentives like the RHI to aid their development and deployment, they will probably fall by the wayside as the march of electrically-generated, greenhouse gas-based refrigeration and aircon continues unchecked. Perhaps after the heating strategy and the RHI we should look to a Cooling Strategy and an incentive to get changes underway – I’ve come up with the ‘Inhibiting Cooling Electricity Carbon Ramping Incentive Measure’ (ICECRIM)… but maybe someone out there has got a better acronym.