Exponential effects of public purchasing subsidies: a full-sample analysis of electric vehicle adoption in Germany

• First study to use a complete national-level dataset. • Combines web-scraped specs with registration data for 69 M individual vehicles. • Finding exponential effects of public subsidies. • No subsidy drops adoption rate to 1.2%; max of €9,000 could have raised it to 20%. This is a first study to employ a national full sample dataset for a socioeconomic analysis of the adoption of electric vehicles (EVs). We use the most recent vehicle registration dataset from the Federal Motor Transport Authority of Germany, which includes the complete underlying population of German vehicle owners. Combining web-scraped data covering all vehicles available in the German market with actual registration data allows a unique analysis of the individual decisions to purchase an EV. While most studies on EV adoption rely on surveys assessing a few hundred to several thousand respondents, our novel approach introduces a method to transform the official German vehicle registration database into a choice experiment format comprising five million observations representing ex-post revealed vehicle choice preferences. We confirm results of earlier studies finding that financial incentives are a most relevant factor for EV adoption, but innovate by finding exponential effects. An average subsidy of approximately €7700 resulted in EVs accounting for 12% of newly registered private vehicles. We estimate that this share would be 1.2% in the absence of subsidies. However, adoption rates would have increased exponentially to 20% if a uniform maximum subsidy of €9000 had been implemented over the entire observation period from 2011 to 2023.