FAQ-page on the carbon footprint of e-cars


Question: E-cars have an efficiency of 80%. Then surely they must be more environmentally friendly than conventional cars?

Answer: Not if you consider electricity generation. E-cars do charge average electricity. But this has to be replaced again in the power grid:

  • Wind turbines and PV systems are not adjustable, i.e. they do not produce more electricity when needed. The green electricity contained in the charging current is taken away from other consumers!
  • Because nuclear power plants practically always run at full load, their share must also be balanced by fossil power plants.

The charging current is thus completely replaced with fossil electricity, and not only in Germany will the primary energy of the compensating current continue to be the particularly dirty coal for a long time to come. The think tank AGORA reported on the crisis year 2020, when electricity demand fell due to Corona:
„In particular, coal-fired power generation reached a new low since holistic record-keeping began in 1990. …The drop in demand affected fossil-fuel generation almost exclusively, as they are behind renewables in the merit order – the deployment order of power plants when selling electricity on the exchange – and thus are the first to reduce their generation.

If the carbon footprint of e-cars is correctly done with coal-fired electricity, they perform worse than cars with internal combustion engines – see the book.

This means:

  1. Who subsidizes E-cars, promotes de facto the sales of fossil electricity.
  2. Every euro invested in electromobility is money lost for climate protection.


Question: Do e-cars perform better than combustion engines when the last coal-fired power plants are shut down?

Answer: No, because if the balancing power in the grid is generated with gas-fired power plants, it’s fair to compare e-cars with combustion engines that are also powered by natural gas. Then the emissions are about the same – see the book. Even then, e-cars have no environmental advantages.

Question: But when the last gas-fired power plants are also shut down, will e-cars finally have an advantage?

Answer: No, because even after that there will be no surplus green electricity.

Reason: The industry must defossilize its production processes and, to this end, partly electrify and partly convert to hydrogen. In Germany, for example, the steel industry is estimated to require 176 TWhi , the chemical industry 645 TWhii, and refineries 82 TWhiii. These three industries alone will require more additional electricity than was consumed net in all of Germany in 2019 (574 TWhiv).

Additional electricity will then only be able to be generated by reconversion of imported synfuels. Generating this electricity in power plants, distributing it via the grid, charging heavy batteries, and carrying them with you on the road all the time does not seem to make much sense. Serial hybrid vehicles with highly efficient internal combustion engines on board would

  • reduce the load on the grid
  • avoid the known raw material bottlenecks and new geographical dependencies due to battery production
  • reduce vehicle weight
  • reduce energy consumption compared to BEVs v and
  • completely eliminate the enormous cost of charging infrastructure.

Question: All the latest studies say that e-cars have much lower greenhouse gas emissions. Surely they can’t all be wrong?

Answer: I am not in a position to say whether they are really „wrong“. The favorable ratings are easy to explain and come from the systematically incorrect application of the average electricity mix.

In this context, the Federal Environment Agency had still clearly stated in 2016 that for the climate balance of the BEV, not the average power mix, but (quote) a „charging power mix“ is to be applied, based on the „power plant park that is actually used for refueling electric vehicles under otherwise identical conditions.“ The UBA explicitly speaks of a „marginal mix, i.e., the power mix that can be concretely assigned to the ‚refueling‘ of electric vehicles, assuming that they join them as an additional market segment under otherwise identical conditions.“
If you now look at the flood of publications in recent years, you come across the phenomenon that these recommendations are consistently ignored. Even the UBA itself has now folded and condones the average mix approach in more recent studies. However, it has never attempted to justify this shift.

Until about 2015, German institutes mostly did a solid job in preparing climate assessments of electromobility (see book). However, the marginal power approach made it impossible to provide policymakers with the desired legitimacy for billions in subsidies to the auto industry. For me, there is no question that it was only abandoned for this reason.

Question: Why should the marginal power approach only be correct for e-cars, but not for fans and coffee machines?

Answer: E-cars are additional electricity consumers. For climate balances of additional consumers, it is necessary to investigate what changes result from their introduction. Average electricity emissions are irrelevant for this; what is decisive is how the power grid reacts to the additional demand. And that is clear: Since Nuclear Power Plants always run at full load and Renewable Energy Electricity cannot be regulated, additional demand can only be compensated by fossil power plants.
Fans and coffee machines are not additional consumers because neither their introduction nor their elimination is under discussion. Ergo, the marginal power approach makes no sense for these products.

Question: Can’t more green electricity simply be produced for e-cars?

Answer: The claim of additional RE expansion specifically for e-cars is a pseudo-argument, because it cannot be refuted that only fossil power plants would reduce output if all e-cars were disconnected from the grid. Moreover, the expansion of renewable energy is de facto independent of the expansion of electromobility.
This truth cannot be shaken: E-cars lower the green power quota. RE expansion reduces greenhouse gas emissions, electric cars increase it again.

Question: Shouldn’t the marginal approach also apply to combustion engine fuels?

Answer: The objection with „marginal fuels“ is misleading, because in Europe there is no difference between the emissions of average or marginal fuels: a marginal additional demand is not served by other sources than the average. There is, nevertheless, a very large difference between emissions of average or marginal electricity. All recent studies try to cover up this difference.



i https://www.derstandard.at/story/2000114434250/neues-verfahren-ermoeglicht-klimafreundliche-stahlherstellung; for the Austrian steel industry, 33 Twh/a are stated there. The ratio of crude steel volumes produced between Germany and Austria in 2019 was 39.6 to 7.42.

ii Roadmap Chemie 2050, https://www.vci.de/vci/downloads-vci/publikation/2019-10-09-studie-roadmap-chemie-2050-treibhausgasneutralitaet.pdf, accessed 26.2.2021

iii Nord/LB, Sector Strategy, Wasserstoffwirtschaft: Chancen, Herausforderungen und Grenzen, https://www.nordlb.de/meine-nordlb/research-dokument-847?cHash=9e803ecf8c7b8daa99764b24f829408c, accessed 21.6.2021.

iv https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy.html

v See „Hochwirkungsgrad Hybridantrieb für nachhaltige Elektromobilität“; Georg Brasseur, Institut für Elektrische Meßtechnik und Sensorik, Technische Universität Graz; https://epub.oeaw.ac.at/0xc1aa5576_0x003b46cd.pdf

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