Mr and Mrs Muster are killing the electricity system

The original article can be read in the “Weltwoche” 20/24 of 16 May 2024.

If all Swiss households adhere to the energy policy recommendations of politicians, the system will collapse.

What are the consequences if Swiss citizens behave as demanded by Energy Strategy 2050? This is illustrated by the example of an acquaintance who gave me an insight into his household’s energy balance sheet. As he wishes to remain anonymous, I will call him Mr Muster. This name is appropriate because, as a homeowner, he has implemented all the measures required to achieve the goals of our energy strategy in the private sector.

Heat pumps and Teslas

Mr Muster lives in a complex of several detached houses located on a sunny plain. A few years ago, he installed a photovoltaic system on his house that fully utilises the optimal side of the roof. Last year, he replaced the fossil-fuelled heating system with a heat pump and bought an electric Tesla to replace his combustion engine car.

How has electricity consumption changed during the critical winter period due to these new purchases? For that purpose, we compare December 2023 with December 2022, when no heat pump was installed and no electric car was driven. As the bills show, electricity consumption in this month increased from 483 kilowatt hours in 2022 to 1400 kilowatt hours in 2023: With the implementation of the decarbonisation measures recommended by the government, electricity consumption in the Muster household has therefore almost tripled.

But how much of this could be covered “green”, i.e. with the yield from the household’s own photovoltaic system? Although the Musters actually produced slightly more solar power in December 2023 than in the previous year, they were only able to cover 10 per cent of their own electricity consumption that month with their own production. But even this poor monthly average paints too positive a picture: it conceals the fact that there were many days on which the solar power input tended towards zero.

Obviously, the electricity was often generated at a time when it was not needed at all.

Only on one of the 31 days was the yield almost high enough to cover consumption. But only theoretically, because as the invoices show, around half of the self-generated electricity had to be fed into the public grid on this day. Obviously, the electricity was often generated at a time when it was not needed. And this also applies to the whole month: even in this winter month with very little solar power, it often flows at a time when there is no demand at all.

All the more reason why the Muster family had to cover their increased consumption with electricity from the public grid. As a result, the amount of electricity purchased from the local electricity company increased by a factor of 3.1 in our December comparison – even more than the consumption itself. If many other homeowners take the same measures as Mr Muster, this poses a major challenge for our public electricity system.

Of course, this only applies to this one winter month. But it is an example of the problems we face in the critical winter period from November to February, when there are many Muster households that clearly need more electricity during this time than without a heat pump or electric car. And as shown, a massive expansion of photovoltaic roof systems will not solve the problem. Nor would batteries or bidirectional e-vehicles help, because there is not enough surplus electricity to charge them. The accounts also show this: Only on five out of 31 days was there a small amount of electricity that would have been available to charge the batteries. However, in no case would this have been enough to even come close to supplying the batteries with electricity the next day.

Only continuous current solves problems

All model households that install a heat pump and buy an electric vehicle are therefore increasing the risk of us running into an electricity shortage in the cold winter months, which could ultimately lead to a blackout. Today, however, all of these sample households are dependent in winter on reliable electricity from nuclear power plants, electricity from storage reservoirs and run-of-river power plants as well as imported electricity: this is the only way to fill the electricity gap, which accounted for 90 per cent of Mr Muster’s demand in December, as shown.