To start with, Fraunhofer ISI collected fleet data from carsharing and ride-pooling providers across Germany – in metropolitan regions as well as rural ones. Based on the reference year 2020, the experts estimated the so-called modal split, how the proportion of shared car services could develop in future in relation to the total volume of traffic. In addition, for the first time at national level, it was analyzed how economically viable the business models are under different regulatory scenarios, and how much greenhouse gases they can save.

The study models the impacts of policy measures in a reference scenario, which assumes a tripling of carsharing vehicles and a quadrupling of ride-pooling vehicles by 2030. Another scenario assumes a doubling of vehicle densities, while a different model estimates the impacts of much cheaper user fees for shared mobility services.

"Our new kind of forecast model shows that mobility services definitely have high potential as an alternative to car ownership, especially in rural areas,” explains Dr. Claus Doll, who researches sustainable mobility at Fraunhofer ISI. "However, it must be carefully monitored which offerings can survive financially in the medium to long term, and make a real contribution to more sustainable transport. The development must be accompanied by a mix of funding and regulation policies.”

How much can the share of carsharing and ride-pooling grow?

If the general framework conditions in terms of charges, subsidies and environmental costs remain the same, the proportion of carsharing in the modal split is expected to grow by 32 percent by 2030. This could double under supportive policy measures, and significantly cheaper user fees could more than triple these trips.

It is expected that ride-pooling could double or even triple for Germany as a whole and in metropolitan regions. In small towns and rural areas, Fraunhofer ISI even calculated increases to almost twenty times today’s offer, which indicates a significant backlog of demand, but also the large potentials of new forms of mobility compared to fixed-schedule rural public transport, which is often unprofitable.

Under extremely favorable conditions with significantly denser services, strongly reduced fares and high prices for using private cars, the model results suggest that it is possible to increase the modal split of shared mobility services to more than two percent in Germany or up to 3.5 percent in cities.

What are the relevant factors for the development of carsharing and ride-pooling?

Crucial factors for the success of carsharing schemes are, above all, mileage-based duties on car use like taxes on CO₂ and fuel, but also waiving the purchase incentives for private cars. These have a much larger impact on the demand for carsharing than parking fees or city tolls that do not depend on the distance driven, regulatory measures or improved public transport. Policy instruments have less overall impact on the modal split of carsharing in rural areas than in cities.

Rising costs for private car use also have positive effects on the success of ride-pooling. However, the decisive factor here is the density of offers. Significantly improving existing public transport is, on the other hand, in clear competition with ride-pooling services.

How economically viable are carsharing and ride-pooling schemes in Germany?

Fraunhofer ISI was able to roughly estimate the economic viability of the ten analyzed scenarios with the help of a broad analysis of cost and revenue indicators inside and outside the transport sector.

This revealed that the best economic conditions for carsharing providers result from supporting public transport and raising environmental prices such as CO₂ and fuel taxes. Radically reducing user fees without any financial compensation is the worst economic option. In particular, fixed membership fees help station-based carsharing to cover its operating costs in contrast to the average of the so-called free-floating schemes.

Ride-pooling offers, on the other hand, do not achieve a promising cost-revenue ratio or a positive operating result in any of the scenarios.

Can supporting carsharing and ride-pooling save greenhouse gas emissions?

On the one hand, car-based mobility services promote car use and make this easier, and thus essentially cause greenhouse gas emissions to rise. On the other hand, depending on the occupancy rate, carsharing and ride-pooling result in more efficient vehicle use compared to private cars and, under favorable framework conditions, have the potential to support the model split towards lower emission modes of transport.

In addition, they promote the use of local public transport by moving away from the perception of cars as the ideal mode of transport for all purposes. The framework conditions that favor them are equally effective in reducing greenhouse gases overall.

In several of the scenarios modeled by Fraunhofer ISI, combining higher costs for using private cars with improved and cheaper public transport achieves an emission reduction of 15.6 megatons or 17.3 percent in 2030 compared to the reference case. Correspondingly, effective climate policy can go hand in hand with support for car-based mobility services.

Recommendations for how to promote carsharing, ride-pooling and sustainability in Germany

The most effective leverage for car sharing services is to set stringent environmental prices. This primarily concerns setting a CO₂ price, which is significantly higher than the currently discussed target of 65 euros per ton of CO₂ equivalent.

If the decision is made to forego a strong increase in the CO₂ price, then stringent charges must be levied for using private cars. Here, town and city councils could make use of local design options given the appropriate legal framework conditions. Sharing services would have to be exempted from local charges such as parking fees and city tools to keep them competitive.

New forms of mobility can compete with traditional public transport, especially if they are promoted via lower prices. Positive effects can be expected, on the other hand, if carsharing and ride-pooling are integrated into the existing public transport system.

Shifting walking and cycling to car-based mobility services should be avoided in order to promote health and sustainability. In addition, legislation should consider accompanying instruments, such as an obligation for local emission-free drives, or a legal minimum occupancy rate for ride-pooling.

The Fraunhofer Institute for Systems and Innovation Research ISI analyzes the origins and impacts of innovations. We research the short- and long-term developments of innovation processes and the impacts of new technologies and services on society. On this basis, we are able to provide our clients from industry, politics and science with recommendations for action and perspectives for key decisions. Our expertise is founded on our scientific competence as well as an interdisciplinary and systemic research approach.