If we want to get rid of fossil fuels nationwide, there is a lot to do.
If we want to get rid of fossil fuels nationwide, there is a lot to do. It will be a generation project, that much is clear. Empa researchers Martin Rüdisüli, Sinan Teske and Urs Elber have now calculated how long and steep the road to a sustainable energy system might be; their study was published at the end of June in the journal "Energies".
The researchers chose a conservative approach and initially collected real data on electricity consumption, heating requirements and hot water consumption in Switzerland. These data then served as the basis for a thought experiment. Switzerland's electricity requirements are still quite easy to determine: The Swiss grid operator Swissgrid provides detailed values for every quarter of an hour on every day of the year. Heating energy and hot water requirements are becoming more difficult. The Empa experts used data from the district heating supplier REFUNA, which supplies several communities in the lower Aare Valley with waste heat from the Beznau nuclear power plant. A data analysis showed that the heat requirement of the connected houses correlates quite well with the outside temperature - and at nights warmer than 18 degrees Celsius, the heat is therefore only used for process water and shower water.
Electrifying heating systems and cars
For their thought experiment, the researchers made various presumptions. Firstly, most Swiss residents behave like people in the lower Aare Valley and live in similar buildings. Secondly, in order to get away from heating oil and natural gas, the heating requirements of all buildings will first be reduced by around 42% through renovation measures; then 3/4 of the remaining heating requirements in houses and apartments renovated in this way will be realised with electric heat pumps. And thirdly: Mobility will be electrified to the extent that approximately 2/3 of all private car journeys can take place electrically, which corresponds to approximately 20% of all kilometres driven. Freight traffic and long-haul journeys, on the other hand, are not so easy to convert, which is why they were excluded from the electrification of mobility in the study.