The Mystery of the “Electric Bill”

When you buy a petrol bike, the math is visible. You hand over a ₹500 note at the petrol pump, and the machine displays exactly how many liters you get. It is a transactional, transparent exchange.

Electric Vehicle (EV) charging, however, happens behind closed doors. It is buried inside your monthly electricity bill, mixed in with your fan, AC, and refrigerator usage. This invisibility breeds skepticism. Many potential buyers in 2025 worry: “Will my electricity bill skyrocket? Will the electric company move me to a higher commercial slab? Is public charging a rip-off?”

This article demystifies the economics of the electron. We have analyzed electricity tariffs across major Indian states (Maharashtra, Karnataka, Delhi, and UP) for the financial year 2025-26 to give you the precise, rupee-for-rupee cost of fueling your ride.

1. The Basics: Understanding “Units” and Battery Size

To calculate cost, you must speak the language of the electricity board.

• 1 Unit of Electricity = 1 Kilowatt-hour (kWh).

• Battery Size: Most popular high-speed electric scooters in India (Ola S1 Pro Gen 3, Ather 450 Apex, TVS iQube ST) have battery packs ranging from 3 kWh to 4 kWh.

The Simple Math: If you have a 4 kWh battery, it takes roughly 4.5 units of electricity to charge it from 0% to 100%. (The extra 0.5 unit accounts for charging losses—energy lost as heat during the AC-to-DC conversion process).

2. Home Charging: The Cheapest Fuel in the World

90% of EV charging in India happens at home. This is where the savings are generated. However, the cost depends entirely on which state you live in and which “Slab” your household falls into.

The “Slab” Effect (2025 Tariff Analysis): Most Indian states use a telescopic tariff structure.

• 0 – 100 Units: ₹4 to ₹5 per unit (Subsidized).

• 101 – 300 Units: ₹7 to ₹8 per unit.

• 300+ Units: ₹9 to ₹11 per unit.

Adding an EV to your home adds roughly 40 to 60 units to your monthly bill (assuming 30 km daily riding).

• Scenario A: The Minimalist User. If your current household consumption is low (e.g., 150 units), adding an EV keeps you in the middle slab.

  • Cost: 50 units × ₹7.50 = ₹375 per month.

• Scenario B: The Power User. If you run ACs and your bill is already 400+ units, every unit for your EV will be charged at the highest slab rate.

  • Cost: 50 units × ₹11.00 = ₹550 per month.

State-Wise Cost of a Full Charge (4 kWh Battery) in 2025:

• Delhi: Subsidized EV tariffs and low domestic rates make it the cheapest. A full charge costs roughly ₹25.

• Maharashtra: With recent tariff hikes, the top slab touches ₹12/unit. A full charge costs ₹54.

• Karnataka: BESCOM rates typically average ₹8.50/unit. A full charge costs ₹38.

The Verdict: Even in the most expensive scenario (Maharashtra top slab), riding 100 km costs ₹54. Doing the same distance on a petrol scooter (at ₹105/liter and 45 kmpl) costs ₹233. Home charging is consistently 75% to 90% cheaper than petrol.

3. Public Charging: The Cost of Convenience

In 2025, India’s public charging network has matured significantly, with Charge Point Operators (CPOs) like Tata Power EZ Charge, Ather Grid, and Ola Hypercharger covering highways and city centers.

However, public charging is Commercial, not Residential.

• AC Slow Charging (Public): Usually found at malls or offices. Rates average ₹14 – ₹18 per kWh.

• DC Fast Charging: Found on highways. Rates average ₹20 – ₹25 per kWh.

Why is it expensive? CPOs have to pay “Commercial Industrial” electricity rates (often ₹14/unit base) plus invest in expensive hardware, land leases, and 18% GST (though GST on charging services is lower, the input costs remain high).

Real-Life Cost Calculation (Public DC Charger):

• Battery: 4 kWh.

• Rate: ₹22 per kWh.

• Full Charge Cost: ₹88.

Is it worth it? Even at ₹88 for 100 km, the cost per kilometer is roughly ₹0.88. Petrol cost per kilometer is roughly ₹2.30. So, even expensive public fast charging is still 60% cheaper than petrol.

4. The “Hidden” Costs: Phantom Drain and Efficiency

To be ultra-realistic, we must account for the energy that vanishes.

Phantom Drain: Modern EVs are “smart” devices. They are always connected to the internet (4G/5G) to sync with your mobile app. This consumes battery even when parked.

• Average Drain: 3% to 5% per week.

• Cost: Negligible (₹10 per month), but it means your range might be slightly lower if you leave the bike parked for 10 days.

Charging Efficiency: No charger is 100% efficient. When you pull 1 kWh from the wall socket, only about 0.85 to 0.90 kWh enters the battery. The rest becomes heat.

• Impact: Your electricity bill reflects what you pull, not just what you store. This efficiency loss is already factored into our estimates above (the “4.5 units for a 4 kWh battery” rule).

5. The “Solar” Hack: Riding for Free

In 2025, the PM Surya Ghar Muft Bijli Yojana (Rooftop Solar Scheme) has exploded in popularity. For homeowners who install a 3kW solar system:

• Generation: ~12 units per day.

• EV Requirement: ~2 units per day.

• Net Cost: Zero.

If you have rooftop solar, your EV effectively runs on sunlight. This is the “Holy Grail” of transportation economics—absolute zero marginal cost for movement.

The Rupee-Per-Kilometer Reality

Let’s summarize the data for 2025:

Fuel Source	Cost for 100 KM	Cost Per KM
Petrol (110cc Scooter)	₹233	₹2.33
Public Fast Charger	₹88	₹0.88
Home Charging (Top Slab)	₹54	₹0.54
Home Charging (Delhi/Low Slab)	₹25	₹0.25
Home + Solar	₹0	₹0.00