• mmbuildingtectonic

The energy generation conundrum

Updated: Feb 23

I would be very pleased to receive the thoughts of others on the following, especially if backed up by statistical data or some logical reasoning.

We all know that as a country we are trying to wean ourselves off fossil fuels, and so understandably there is much discussion about the future of electricity generation, possible methods for the storage of electricity and ways to reduce energy demand. There is also an emphasis by the energy industry and the UK Government on heat pump technology. It is primarily this last bit that concerns me, and I lay out below why I am so concerned. Kindly note that I am using hastily assembled figures upon which I base my argument, but I think the problem is so manifest that even if I am 50% out with my figures, my reasoning will still stand and my concerns would still be justified.

At the moment, less than 5% of houses in the UK are purely heated by electricity from the grid, with most of the other 95% being heated by piped gas or stored gas/petroleum. The government is talking about banning domestic gas boilers in due course for new houses, and so the inference is that eventually, we will all be heating our buildings with electricity generated without burning fossil fuels.

Great stock is being placed on solar energy. Clearly, we will need huge wind farms and fields of solar panels if we are to ramp up enough generation to heat the 95% of housing that at the moment are heated by gas and oil boilers. I am willing to concede this may be possible, but only while the sun is shining or the wind is blowing. So the other great necessity is that we can store electricity in times of surplus and meter it out the rest of the time. The methods suggested involve huge banks of batteries or pumping water uphill to drive hydroelectric turbines etc. It's hard to imagine the scale of this endeavour given we would need to generate twenty times more electricity at peak times for heating than we do now. Except that the consumption will be reduced by heat pumps- at least this is the hope of the government it seems; and this is my major concern.

We are also being told that heat pumps will ease the burden on energy consumption because a heat pump uses electricity to extract heat from the surrounding air or ground. For instance, for one watt of electricity input, you may be able to extract say five watts of heat from the surroundings. However, this is only true when the surrounding substance is relatively warm and this ratio (called the coefficient of performance, COP for short) drops off when these surroundings are cold.

So during a sustained cold period of say 3 or 4 days when the air temperature has remained at about zero and the ground temperature is near freezing, the heat pumps extracting heat from below ground have chilled the surrounding soil to near zero, so the COP of our heat pumps has dropped to 2 (one watt of energy in to get 2 watts of heat out - and according to some studies even this may be optimistic). In this case, we will not be able to rely upon anything like the benefit lauded by the heat pump industry. Okay, it will help, and we may only need to generate ten times the electricity we do at the moment. It's also worth noting that when the demand will be at its greatest and the heat pumps are least able to help, it may also be a dark windless night; so no solar power would be available.

Let me go through this again- crudely, I accept. Say we have just enough electricity consumption at present when demand is at maximum, the 5% of buildings heated through electricity have been joined by the other 95%, so that is 20 times more electricity needed for heating. Even if this was mitigated because we all have heat pumps, it would still require 10 times as much electricity to be produced. Where is it going to come from? Banks and banks of batteries or reservoirs of water with infrastructure to match- I don't think so.

So what is the answer? I don't know and so this is why I am worried about this. I notice we are also being softened up as a nation in respect of the nuclear option, and new nuclear power stations are being considered such as smaller cheaper ones made by Rolls Royce. This may be our only answer but here is the dichotomy for me, given that nuclear power is difficult to turn on and off and the huge cost is in the building of the infrastructure and not the running of it, why bother with solar power. We will be producing excess power when it's sunny and windy from the equipment we needn't have bothered with.

Now, don't get me wrong, I would prefer the solar option but I think we are being sold a pup by the government and the heat pump industry, and I do not see the above arguments being aired anywhere. So please let's discuss this.

Further points for discussion may be the bigger picture of our energy infrastructure, such as how we are going to keep our industry competitive or even still operating with a shortage of electricity generation. Also whether there is a place for Blue or even Green Hydrogen and the possible retention of our gas pipe and home boilers infrastructure. Upgrading the insulation of our housing stock must also be on the agenda, but in the light of the massive shortfall of energy supply we are facing, this is no overall solution. Regardless it does need to be addressed in my view.

I am really looking forward to getting this discussion going.

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