Keralam Plans 100-EV Vehicle-to-Grid Pilot With IIT Bombay — Homes Could Cut Bills 30 Percent

EVs as Power Banks

Keralam is preparing a pilot that would connect more than 100 electric vehicles to the grid, testing whether their batteries can supply power to homes and, eventually, back to the network. The Keralam State Electricity Board signed a memorandum of understanding with IIT Bombay in July 2025 to explore the technology, and the pilot would use the state's EVs as a distributed energy resource.

The idea has two forms. Vehicle-to-Home, or V2H, lets an EV battery power a house. Vehicle-to-Grid, or V2G, goes further and lets the battery feed electricity back into the grid during peak demand. IIT Bombay's Grid Integration Lab has spent three years running experiments, and in one trial a car was charged using solar power during the day and then supplied electricity to a professor's home at night, trimming that household's bill by around 30 percent.

What the Tests Found

The key question for any EV owner is battery wear. Professor Zakir Hussain Rather of the Grid Integration Lab said the trials found no significant impact on battery life from supplying electricity to homes. Battery health, measured as State of Health, typically starts at 100 percent on a new pack, and the researchers reported it fell by only about 1.5 percent over two years of use in the study.

Element	Detail
Partners	KSEB and IIT Bombay Grid Integration Lab
Pilot size	More than 100 EVs
Bill reduction in trial	About 30 percent for one household
Battery health impact	About 1.5 percent decline over two years

The technology also solves a second problem: storing surplus solar power. An EV could soak up cheap daytime solar and return it at night, when demand peaks. That is exactly the kind of flexibility India's grid will need as it adds more renewable capacity.

The Roadblocks

The biggest hurdle is hardware and rules. Most EVs sold in India are not configured for V2G, and IIT Bombay is working on the technical modifications needed to make selected models capable. There is also no regulatory framework for two-way power flow, which is why the pilot is a test rather than a scheme. Two-way chargers cost more than standard home units, and the economics depend on how utilities price the power they buy back.

What This Means for Buyers

Nothing changes for an EV buyer today. But the direction is worth noting. India's EV count is climbing fast, and FADA data shows electric vehicles reached roughly 13 percent of overall registrations in September 2026, with EV penetration in passenger vehicles at 8.45 percent. As that fleet grows, its batteries become a national asset, not just a private one. If you are buying an EV now, the ability to support V2G later could become a resale and utility feature rather than a gimmick. You can estimate your own EV running costs on our EV calculator and track adoption trends on our sales dashboard.

(Sources: KNN India, IIT Bombay Grid Integration Lab, Keralam State Electricity Board, FADA September 2026 retail data. Images: Wikimedia Commons, CC BY-SA 4.0)

::KEY_NUMBERS:: Pilot size | 100+ EVs Bill reduction in trial | about 30 percent Battery health drop | about 1.5 percent over two years MoU signed | July 2025 ::TLDR:: KSEB and IIT Bombay will connect 100-plus EVs in a vehicle-to-grid pilot In a trial, a car charged on solar by day and powered a home at night The household bill fell about 30 percent Battery health declined only about 1.5 percent over two years ::CHART:: type: line title: Battery state of health over two years (percent) labels: Start,Year 1,Year 2 values: 100,99.3,98.5 source: IIT Bombay Grid Integration Lab trial ::GLOSSARY:: V2G | Vehicle-to-Grid, feeding power from an EV battery back into the grid V2H | Vehicle-to-Home, using an EV battery to power a house SoH | State of Health, a measure of how much battery capacity remains ::PULLQUOTE:: If a car battery can run a house at night without ageing much, the case for treating EVs as power infrastructure writes itself. ::PROS:: Could cut household electricity bills Uses surplus daytime solar Trials found limited battery ageing No extra public chargers needed for the test ::CONS:: Most Indian EVs are not configured for V2G No regulatory framework yet Needs two-way chargers, which are costly Still only a pilot, not a nationwide scheme ::POLL:: Would you let your EV battery power your home? || Yes, to cut bills || No, battery life worries me || Only if paid for it ::SOURCES:: KNN India, IIT Bombay Grid Integration Lab, KSEB