A complete switch to electromobility in German passenger cars would increase electricity demand by almost 20 percent. Compared to a situation without an expansion of electromobility, this would require more power generation from fossil fuels - assuming that the availability of renewable energies is the same in both cases.
According to the study by the Institute for World Economy IfW, electric cars thus lead to greenhouse gas emissions that are 73 percent higher than those of modern diesel cars that comply with the Euro 6 standard. This is because it is more climate-friendly to use renewable energies to reduce the proportion of fossil fuels - especially coal - in the electricity mix than to use them to fuel electric cars.
Electric cars run on 100 percent coal-based electricity
»Nowadays, electric cars run de facto on 100 percent coal-fired power," says Prof. Dr. Dr. Ulrich Schmidt, who heads the "Social and Behavioral Economics Approaches to Solving Global Problems" department at the IfW. "This is because the share of renewable energies in the electricity requirements of electric cars is not available to displace fossil fuels elsewhere, and the increased demand for electricity requires the additional use of fossil fuels«.
In the Kiel Policy Brief »Electromobility and Climate Protection: The Big Miscalculation«, Schmidt has reviewed the climate balance of electromobility, taking into account the rising demand for electricity and the electricity mix. »Only when the energy turnaround is well advanced and the electricity is almost exclusively from renewable energies will the electric car be more climate-friendly than modern diesel vehicles«.
According to the Federal Motor Transport Authority, passenger cars alone will have covered a total of 630.84 billion kilometers in 2018. Assuming an average consumption of an electric car of 15 kWh per 100 kilometers, this would result in an electricity requirement that would correspond to 18.4 percent of the net electricity generation in Germany if the switch to electric mobility in the passenger car sector were complete, according to Schmidt's analysis.
Higher electricity demand often remains unconsidered
In two recent studies, which also give a positive assessment of electromobility in terms of climate aspects, the significant increase in electricity demand is not taken into account and thus leads to an improved picture of electromobility. »Even if the car is refuelled with 'its own' solar power, as one of the studies recommends, it would be more climate-friendly to feed it into the power grid and thus reduce the proportion of carbon-based electricity,« Schmidt writes.
The EU Commission estimates that even in 2050 the share of fossil fuels will still be around 40 percent. This means that even then, electric cars would still be running on 100 percent coal-fired power and emit around 300 g CO2 per kilometer, whereas modern diesel vehicles, according to an ADAC study, emit only around 173 g CO2.
Permitted emissions are legally limited
The emissions-driving effect of electric cars in the transport sector will at least be cushioned thanks to the European emissions trading system. This system limits the total emissions of the energy and industry sector upwards, while transport is not included. If emissions in the energy sector increase due to electric mobility, this forces a reduction in the industrial sector. Only through this effect can electromobility currently contribute to climate protection.