Grid Integration of Electric Vehicles

Preparing institutions for the shift to electric mobility

To ensure the shift to electric mobility happens efficiently, it is helpful to prepare institutions to take advantage of various synergies. Electric mobility touches many sectors, not only mobility and power, but also the building and real estate sectors. To engage efficiently across these sectors and support planning, silos in ministries as well as in the industry need to be broken down.

Policymakers should start creating multidisciplinary working groups, serving as focal points for stakeholders to learn about the concerns and motivations of other parties. Here, common frameworks can be developed to help push electric mobility forward.

Silos can be broken by establishing co-operation at the policy-making level and designating contact persons to be in charge of cross-sectoral co-ordination in order to maximise synergies.

Assessing the impacts of electric mobility on the power sector

EVs will impact the power system based on their power and energy requirements and on the grids from which they are charging. Problems may not be encountered when EVs charge simultaneously or fast charge in commercial or industrial areas, but may be encountered in residential areas. When EV charging reaches peak electricity consumption, even with sufficient network capacity, this will increase marginal generation requirements and result in additional system costs.

If the charging infrastructure is available, most commuters with personal EVs mainly recharge in the evening at home or during the day at work. E-buses and e-trucks require high charging power for overnight charging at depots and even higher power for mid-travel stops. Therefore, it is important for policy makers to develop an electric mobility strategy that considers all of these factors to determine the vehicle electrification priorities and accompanying charging solutions.

Data on travel needs and charging patterns can be obtained through travel surveys. Besides this, GPS technologies and charging databases can provide insights for policy makers and aid in modelling EV uptake and charging profiles. However, there are always forecasting uncertainties. To anticipate these, policy makers can use mobility scenarios when assessing the impacts on the grid to ensure that decisions on grid investments can adapt to possible changes in the landscape.

Moreover, dedicated studies are necessary to adequately assess and plan for grid impacts as a result of variations in local mobility and power system contexts.

Deploying measures for the grid integration of EVs

To help policy makers prioritise charging strategies according to the conditions of their EV uptake and power system needs, this manual provides a simple framework for EV grid integration. The framework is structured around four phases that correspond to increasing volumes of flexible EV load and increasing system demand for flexibility.

• The main strategy is to maximise the amount of managed charging, as opposed to unmanaged charging. Cost-effective charging solutions that help accelerate the shift to electric mobility should be accommodated by the grid, but opportunities to maximise the share of managed charging should be pursued when possible.
• Individual EVs may be too small to participate in most power markets, but this can be resolved through standardisation and interoperability measures, thereby aggregating sufficient numbers of vehicles.
• Electric mobility is also an unprecedented opportunity to grow the share of variable renewables in the power system. EV charging can be co-ordinated with variable renewable energy generation through incentives and measures to allow the contracting of renewables capacities.
• Finally, with all of the potential benefits of managed charging, policy makers should incentivise the smart-readiness of ecosystems through minimum communication and control requirements.

Improving power system planning

To ensure the power system is ready to accommodate and take advantage of the electrification of transport and its potential cost savings, a fundamental improvement in planning practices is required.

Integrated and co-ordinated planning practices are becoming essential to ensure power sector plans are well co-ordinated with other sectors. Grid planning needs to be proactive and anticipate various needs for expansion, instead of responding to new requests for connection.

The full value of EV charging needs to be reflected in the scenarios and plans for the power sector. Revisiting regulatory design to reduce bias on capacity expenditure grid operators can put more focus on leveraging available flexibility and reducing costs for everyone. Moreover, revisiting criteria for grid expansion and system planning can help ensure that the cost savings from EV charging flexibility are recognised and accounted for when developing grids.