Source: Energy & Management Powernews, February 22, 2022
The climate footprint of electromobility depends largely on the charging current used. Researchers investigated how widespread green electricity is among electromobilists.
If one bases the calculations of the ecological footprint of e-vehicles on the CO2 emissions of the German power grid, various studies already show a high saving in greenhouse gas emissions. If, on the other hand, the electricity used in the charging process consists exclusively of renewable energy sources, the emission value is reduced again significantly to up to 75% compared to conventional vehicles.
With this in mind, the Fraunhofer Institute for Systems and Innovation Research ISI and Dresden-based "Energy Systems Analysis Associates" (ESA2 GmbH) analyzed the extent to which drivers of electric vehicles really think green.
For this purpose, the researchers took three things as a basis: the proportion of green electricity contracts for charging firstly at the home wallbox, secondly at work and thirdly at public charging stations. They also looked at the ecological claim of the green power contracts concluded. They also compared the values for Germany with the EU average. The survey included responses from a total of 867 respondents. They were asked about their preferred charging locations and whether they use green electricity for charging.
High proportion of green electricity at all three charging locations
The results of the survey show that 59% of respondents in Germany prefer charging at home. The EU average is 64%. 84% of electric vehicle users have a green electricity contract (EU: 63%). According to the survey, this is well above the average for German households, of which only 30% had such a contract in 2020.
As reasons for the higher proportion of green electricity customers among electric vehicle users, the study points to their greater environmental awareness as well as the government subsidy for wallboxes, which in 2021 was linked to the conclusion of a green electricity contract.
According to the survey of fleet managers, charging at the workplace, which applies to 14% (EU: 18%) of charging processes, is also linked to green electricity contracts with similar frequency. Here, Germany comes in at 81% and Europe at 60%.
This also applies to public charging points, as the evaluation of various data sources shows: for example, the contractually agreed green electricity share at public normal charging stations in Germany is at least 85% (EU: 62%) and at public fast charging stations at least 75% (EU: 57%). The share of green power contracts thus turns out to be very high at all three charging locations (home, workplace, public charging station) in Germany.
Ecological claim of the contracts varies greatly
According to Fraunhofer, however, major differences were evident in the black-and-white print of the green power contracts: Thus the ecological requirement of the contracts begins already with the recourse to Herkunftsnachweise, whereby usually old plants for the production of renewable river without spatial or temporal relation to the current acceptance are assigned to the Ökostromvertrag. In contrast, ambitious green power contracts with high ecological standards, which can be proven via externally certified green power labels, would be the case.
Many of the respondents, according to another result of the survey, did not provide any information on the labels or did not know anything about them. Fraunhofer justifies this with the varying requirements and the multitude of different labels. State specifications could provide here for more transparency and a larger acceptance of fastidious green electricity contracts, it is said on the part of Fraunhofer.
In addition to the green electricity contract, e-car drivers use their own photovoltaic system with their own electricity storage during their charging process at home. Thus, at 48%, almost half of those surveyed said they also owned a PV system.
Public charging is gaining ecological significance
When looking to the future, the researchers consider both directions possible in the development of green power contracts.Sabine Preuß, coordinator of the survey at Fraunhofer ISI, believes that on the one hand it is conceivable that the share of green power in charging will continue to increase. The reason: green electricity is becoming the social norm and is playing a decisive role in shaping environmental awareness.
However, on the other hand, the proportion of people who have fewer opportunities to fall back on self-generated renewable electricity sources when charging their e-cars is also rising - "for example, because they live in rented apartments and cannot install PV systems. Therefore, a declining share of green power contracts is equally conceivable," Preuß concludes. In this case, charging at the workplace and at public fast and normal charging stations could increase, and the green electricity tariffs there could gain relevance for the ecological footprint of electric vehicles.
Author: Davina Spohn