The end of gas boilers: Challenges of switching to electricity and evaluating the government's plan

In the previous blog, I outlined how a more efficient technology may provide a heating solution that meets the government’s zero carbon strategy; electric heating provided via an air source heat pump (ASHP). But what are the practical challenges we face to making this a realistic prospect?

Heat pumps are pricey

A major financial problem is that the cost of an ASHP can be around £8,000 to £16,000, while a gas boiler may be only around £2,000 to £3,000. Asking people to pay five times more for their heating system is not going to be popular either, and the government are gambling on the price of ASHP being cut in half by industry, though it is not clear if this will be possible, enough, or even acceptable for householders.  In response, the government are proposing to provide a £5,000 grant for the first 30,000 households to install an ASHP over the next three years. Currently, however, we already installing over 30,000 ASHP per year in the UK; so, it is possible this support will simply subsidise those households who were already going to install an ASHP, rather than stimulate new demand to drive down costs. If they do not drop, the purchase price of ASHP may scupper the entire strategy. However, there are more problems to consider beyond increased cost of heat.

It’s not simply swapping the boiler

We need to change how we think about heating our homes; currently, with our gas boilers, when we are cold, we turn on the heating and a few minutes later we are warm. With a low temperature ASHP we need to get used to slow response times and turning heating on in advance of when we want to be warm, to give the system a chance to respond. This is a concern since heating controls are already notoriously mis-understood, and there is the potential that households will be uncomfortable if they do not adapt how they use their heating.

The UK electricity grid is not ready

The main technical problem with mass electrification of heat is that the UK electricity grid is sized and designed to supply only our appliance and lights in our homes as well as some industrial applications and a limited amount of heating. The UK’s electricity annual use profile is therefore relatively steady throughout the year fluctuating around 500 GWh per day. The annual consumption profile for gas couldn’t be more different; the gas grid has been designed to provide almost no gas during most of the year but to provide an excessive spike in demand, up to 3,000 GWh per day, when we all turn on our heating on cold winter’s mornings, so called “peak heat”. Thus, the UK electricity grid needs to be upgraded to be able to provide perhaps 6 times greater capacity, something that is not practically or financially viable. Conventionally therefore, it is agreed that houses need to have their energy efficiency improved, to reduce peak heat, before nationwide switching to electric heat may be possible. 

Not enough money

To stand a chance of succeeding, the new government zero carbon heat strategy needed long term support in the order of tens of billions of pounds per year for decades. It also needed to be under an umbrella of a National Retrofit Strategy to ensure the fabric first issues could be addressed. The indications from the published strategy document are that the government is only willing to provide short term three-year support in the order of several billion pounds, gambling that industry can pick up the short fall. The government has provided £60m of innovation funding as part of the announcements to allow industry to react, though in terms of industrial research, this money will not stretch very far.

New jobs for plumbers?

The Government are quick to point to the predicted 240,000 jobs that electrifying heat could bring, however, it is not clear if these may be new jobs or simply retraining existing gas engineers to be ASHP engineers. If the latter, there was little detail around the financial support needed for retraining the industry. In the short term when skills may not match the new needs there is likely to be a problematic transition period, similar to that suffered by other new and emerging industries which could have reliability and trust implications for householders. Other new technologies in the housing industry where this transition period caused problems was the installation of mechanical ventilation systems, for which reports suggesting that in its early days, almost all new systems were not installed or commissioned properly. 

Conclusion

One thing is clear, the Government’s strategy hasn’t fixed the problem. The issue of zero carbon heat will not go away and more policy and strategies will keep coming back over the next few decades. The second thing that is clear is that the scale of funding and support provided by this strategy is clearly inadequate, so this is a missed opportunity to give the industry and householders a clear guide and framework to achieve zero carbon heating. The potential that decarbonised electricity and electrified heat can provide is exciting and could provide a significant support perhaps providing zero carbon heat to millions of homes, though this will depend on the future costs of ASHP themselves and the cost of electricity. It is not clear how this can provide a solution for all 28 million homes in the UK. The potential of hydrogen is huge as are the uncertainties that surround it, which have not been properly explored in this strategy. Some solutions have not been considered at all in this strategy, for example, the potential for greater local storage of electricity in the grid, perhaps through house batteries, to supply the problematic peak heat to people’s homes. Meanwhile, some solutions have not received as much support or attention as they should, for example, the lack of funding for and description of a national retrofit strategy is perhaps the biggest omission of them all. Thus, the current strategy released today is simply the first few steps, it may be several years or decades before a clear route to zero carbon heat for all can be drawn.