How can smart charging steer electric vehicle uptake in India?

The government of India announced ambitious energy transition plans at COP26, saying it will deploy 500 GW of renewable electricity generation capacity by 2030 and sign up to the global EV30@30 campaign.

The renewables plan would triple India’s renewables capacity and the campaign calls for electric vehicles to make up at least 30% of new vehicle sales by 2030.

These two ambitious targets are closely connected. Shifting the country’s vehicle fleet from internal combustion engines to electric motors will further trim emissions if accompanied by an accelerated decarbonisation of India’s power sector. At the same time, electrifying road transport will unleash a tremendous number of distributed energy sources, which – if properly piloted and managed – could help absorb surplus solar and wind generation, reduce costs for consumers and utilities, and further incentivise EV adoption.

Beyond spurring EV sales, policy support for charging infrastructure and incentives for grid-friendly charging are essential to realise this potential, in particular to encourage daytime charging to absorb abundant solar output during the day.

Scaling up solar PV and EVs presents potential challenges and opportunities for power systems. Large amounts of PV capacity can lead to excess generation availability during the day, resulting in curtailment.

At the same time, the natural tendency to recharge cars after returning home from work can add significantly to evening peak loads just as the sun is setting, stressing grid capacities and boosting required generating capacity, which may be met by fossil fuel generators.

On the other hand, these two technologies can complement each other if EVs can be charged during daylight hours with cheaper, cleaner electricity, at the same time helping integrate solar generation

Time of use tariffs are currently one of the main measures to incentivise system-friendly EV charging patterns. In today’s India, time of use tariffs incentivise night-time charging, there by reducing peak loads. However, as solar generation plays an increasingly large role in the power mix, the key will be to shift charging to the daytime when solar output is high.

In order to illustrate the impacts of different charging strategies in a future Indian power system, we modelled several different charging cases in the context of the World Energy Outlook’s Announced Pledges Scenario in India for 2030 using the IEA’s India Regional Power System Model. The Announced Pledges Scenario includes all recent major national announcements as of September 2022 for 2030 targets and longer-term net zero and other pledges.

For this assessment, 80% of plug-in light duty vehicles and 2-to-3 wheelers are assumed to follow one of four different charging patterns: baseline, night, day, and dynamic (optimised) charging. This evaluation aims to illustrate the potential benefit of specific charging approaches if adopted by most eligible vehicles, with 20% of the fleet remaining on the baseline pattern to account for limitations in the availability of vehicles for charging. Commercial vehicles and trucks are excluded because of their tighter time constraints for charging, especially during the workday.

We look at three types of impact that EVs can have on the system: increased peak electricity demand costs, operational costs (e.g. power plant fuel consumption) and CO₂ emissions associated with charging. The first finding is that while night charging in this scenario can substantially reduce the peak electricity demand impact of EV charging, it has only a small benefit for operating costs and even less for emissions. This is because increased night-time demand is met primarily by coal, so while it avoids the need for increased capacity it still entails similar operating costs and emissions.

By contrast, a fixed charging pattern with EV load concentrated during the daytime results in the same reduction in peak costs accompanied by a much larger reduction in operating costs and a substantial reduction in the emissions associated with EV charging. If the benefit were entirely passed on to EV users, this would translate in a reduction in energy component of the charging cost from 0.41 to 0.29 USD per kWh. This illustrates that even a fixed time of use tariff structure could deliver large benefits, but the key will be to ensure that the timing is aligned to hours of high solar production rather than focusing only on peak load reduction. There is also the need with time of use tariffs to manage the risk of creating new load peaks due to coincident charging, where a specific tariff encourages too many users to charge EVs at the same time.

Further improvements in managing the EV fleet and ensuring their active participation in system balancing and emissions reduction can be achieved through vehicle-to-grid approaches. Vehicle-to-grid allows for both managed charging and discharging of EVs and, with the right tariff structure, can contribute to both balancing the power system as well as reducing EV owners’ charging bills.

EVs with vehicle-to-grid capabilities could potentially provide a large contribution to the power system. The services they can provide encompass both the ability to meet peak demand and an improved ability to provide ancillary services since each vehicle’s battery can both charge and discharge to smooth fluctuations in demand or supply, in effect acting as distributed storage.

Enabling vehicle-to-grid EVs in India faces similar challenges to smart charging, as well as additional barriers. These include complex value chains, the need for strong communication networks and protocols for linking with the grid, consumer acceptability and a need for mechanisms to reward providing ancillary services.

This work forms part of the Digital Demand-Driven Electricity Networks Initiative, supported by the Clean Energy Transitions Programme, the IEA’s flagship initiative to transform the world’s energy system to achieve a secure and sustainable future for all.