October 2, 2025
How Solar and EV Charging Work Together
Rooftop solar and EV charging are a natural pair. Solar panels produce power during the day, and your car is often parked at home or at the office during those same hours. Connecting the two means you can drive on sunlight instead of grid electricity, cutting both costs and carbon emissions.
The Basic Setup
A typical rooftop solar system in India ranges from 3 kW to 10 kW for residential installations. A 5 kW system generates roughly 20-25 kWh per day depending on location and season. If your EV consumes 15 kWh per 100 km and you drive 40 km daily, you need about 6 kWh to recharge. That is less than a third of your solar output.
The remaining solar energy powers your home or gets exported to the grid. With solar-to-EV charging, your fuel cost drops to effectively zero for daily driving.
Solar Excess Charging
The smartest approach is solar excess charging. Your home loads get first priority. Whatever solar production remains after serving those loads gets directed to the EV charger. This maximizes self-consumption and avoids exporting at low feed-in tariffs.
- Requires a smart charger that can adjust power output based on available solar
- RIOD chargers with Power Master integration do this automatically
- Charging speed varies throughout the day as cloud cover and home loads change
- Minimum charging threshold is typically 1.4 kW (6A single-phase) per EV standards
Adding a Home Battery
A home battery stores excess solar energy for evening and nighttime use. Without a battery, any solar production that exceeds your daytime consumption goes to the grid. With a battery, you can charge your EV after sunset using stored solar energy, achieving near-complete energy independence for your vehicle.
Battery costs are falling but remain significant. A 5 kWh home battery costs Rs 1.5-3 lakhs. Whether it makes financial sense depends on your grid tariff, feed-in rate, and how much of your EV charging happens at night.
Financial Returns
A 5 kW solar system costs roughly Rs 3-4 lakhs installed (after subsidies). If it offsets Rs 3,000 per month in electricity and Rs 3,000 per month in petrol costs (replaced by solar EV charging), the payback period drops to around 3 years. Without EV charging, the payback on the same system is 5-6 years.
Adding EV charging to an existing solar installation is one of the highest-return energy investments a homeowner can make.
Deploying EV charging?
Talk to our team about your project. We design, supply, and manage EV charging infrastructure across India.