The EU has set a target for reducing its greenhouse gas emissions: 40% below 1990 levels by 2030. In the transport sector, CO2 emissions is responsible for largest share of total greenhouse gas emissions.
A comprehensive policy package including mandatory CO2 emissions standards and an increase in fuel taxes in all EU member states, would yield an estimated 14% overall annual reduction in CO2 emissions by 2030 compared to 2005. To achieve these objectives, the states are developing the electric vehicle network. The incentive goes so far as to qualify most electric cars as "zero- emission" vehicles. It is also at 0 g CO2/km that EVs are compatibilized for the manufacturers!
The explosion in the number of EVs will increase the demand for electricity. The CO2 emission reduction potential of these transport solutions depends directly on the energy mix involved in the vehicles' charging. If we consider the comparison between Germany and France, we notice that charging a car in France mainly involves nuclear electricity production. On the other hand, large fluctuations in the electricity supplied by photovoltaic and wind turbines can be observed in Germany. The potential for reducing CO2 emissions is directly linked to the production method, and thus becomes relative to the time and place of the charging.
If we focus on France and Germany, the forecasts of these states remain optimistic as to the increase in the number of electric cars. To estimate electricity consumption in the medium term, all the scenarios assume a massive diffusion of electric vehicles. For France, a fleet of 15.6 million electric vehicles is planned in RTE's "high" trajectory and corresponds to a purposely optimistic hypothesis compatible with the objectives of the Climate Plan announced in July 2017... In Germany the objective is as follows: an existing stock of about 500,000 vehicles is established by 2020, to be increased to 3 million vehicles by 2030. By 2050, 25 million vehicles will be on the road, meaning that 37% of the kilometres travelled will be powered by electricity by that year.
With a market simulation algorithm (PowerAce, “analyses the impact of different market designs energy-only-market, strategic reserve, capacity markets”), it has been possible to conduct an analysis of the distribution of CO2 emissions caused by the load of EVs over the regions of France and Germany. A fleet of electric vehicles imposes a load on the energy grid relative to an EV diffusion scenario over time. Investment decisions should therefore be influenced by the presence of EVs and the demand they impose over time. By 2030, some regions will see the number of EVs impose a new and significant load that could cause emissions peaks if no anticipatory measures are taken. Now that CO2 emissions have a price, the incentives are greater. These observations should motivate new investments in the network or the introduction of financial measures to encourage users to adapt their use of EVs (in terms of charging behaviour) and reduce emissions.
Introducing renewable production solutions is a challenge in dense residential areas. Indeed, the ground area is limited, and demand is very high. The potential renewable energy created on the outskirts of cities must therefore be transported, at high cost, inside cities. It was noted that some areas on the periphery close to the cities emitted a great deal of CO2 at late hours, which corresponds to users’ return home from work. These lower-density regions have greater potential for renewable energy production. If EV demand is still located on the periphery, it is conceivable to incentivise users to recharge their cars at home late at night in order to relieve the city where these people work. This is a case where recharging during the day (at work) does not seem to be a winning solution from the point of view of CO2 emissions. In France, it was also observed that the presence of significant nuclear production makes it possible to reduce CO2 emissions from EVs. Because EV are going back home late in the day, households begin to consume less when cars are plugged in. Nuclear plants are getting involved in the production (maintaining a steady power) for EVs and emissions remains low even with a significant demand.
Focusing the study on the organisation of the territory, it can be noticed that although some cities emit a significant amount of CO2, the largest proportion is distributed over the entire territory in regions that have a density of between 100 and 1,000 inhabitants per square kilometre:
Density-based ranking of German emissions:
Density-based ranking of French emissions:
Electric mobility solutions offered by car manufacturers now include fast-charging options. Loading powers are expected to be around 150 KW by 2020. Increasing the loading speed is often considered to be one of the main conditions for the wider use of electric cars in Europe. Such scenarios are therefore often accompanied by greater load power than the usually simulated 3.7 KW power. However, home charging will remain within an order of magnitude of this power and this remains the largest proportion of the charging cycles. If the diffusion is partly indexed on the means of the users and the fast loading is democratised, we must expect very high requests during travel for holidays for example. Electric vehicles are therefore likely to cycle loads outside their normal journeys and will cause high peaks in demand, and local power along highways will be needed.
In the end, it is important to note that fast charging can also bring an extra dimension to the smart charging configuration. This short-term capacity should make it possible to store energy at a time when production is too high. The opportunities for cities and mobility management are as high as the expectation. Utilities, Car manufacturers, government should work close from one another to take on these strategic challenges.
European Commission Publications Office, "Share of EU energy consumption from renewable sources, 2005-2050".
EEA, "Renewable energy shares by sector in the EU," 2017
The International Council of Clean Transportation, "2020–2030 CO2 standards for new cars and light-commercial vehicles in the European Union," 2016.
RTE, "Bilan prévisionnel de l’équilibre offre-demande d’électricité en France," 2017.
infas, "Mobilität in Deutschland 2008," 2008. [Online].
M. Wann-Jiun, G. Vijay and T. Ufuk, "Distributed Charging Control of Electric Vehicles Using Online Learning".
C. Carolina Perpiña, S. Filipe Batista e and L. Carlo, "An assessment of the regional potential for solar power generation in EU-28".