Installing solar panels can lower your electricity bill, but many people still wonder what happens to the power they do not use. This is where a net meter helps. It records the electricity your home takes from the grid and the extra solar power your system sends back.
A net meter is a two-way digital electricity meter. A regular meter records only the power you use. A net meter tracks power in both directions, which makes it a key part of an on-grid rooftop solar system.
What is a net meter?
A net meter connects your home solar system to the local electricity grid. It records two types of power:
- Import: Electricity your home takes from the grid.
- Export: Extra solar electricity your home sends to the grid.
The meter keeps a record of both figures in units, also called kilowatt-hours or kWh. Your electricity provider uses this data to work out your monthly bill.
How does a net meter work during the day?
Solar panels produce electricity when sunlight falls on them. Your home uses this power first. Fans, lights, refrigerators and other appliances can run on solar energy during the day.
If the panels produce more power than your home needs, the extra electricity flows into the grid. The net meter records these units as exports. This can happen when the family is away, when fewer appliances are running or when the sun is at its strongest.
For example, your solar system may produce 5 units in an afternoon while your home uses 3 units. The remaining 2 units can move to the grid. The meter records those 2 units as exported power.
What happens at night or during cloudy weather?
Solar panels produce little or no power at night. They may also produce less electricity on a cloudy day. At these times, your home draws power from the grid as it did before the solar installation.
The net meter records this electricity as imported power. In an on-grid system without batteries, the public grid works like a shared power bank. You send extra power to it during the day and draw power from it when your panels cannot meet your needs. There is no giant battery hiding under the bed, which is good news for both space and cost.
How is the monthly bill calculated?
The basic calculation is:
Net consumption = Imported units minus exported units
Suppose your home imports 300 units from the grid in one month. Your solar panels export 250 units during the same period. Your net consumption will be 50 units.
In this case, the energy charge may apply to 50 units instead of 300 units. If your exported units are higher than your imported units, the extra credit may carry forward or may be paid under the rules set by your state electricity regulator.
Keep in mind that a lower energy charge does not always mean a zero bill. Fixed charges, meter charges, taxes and other fees may still appear. The exact billing method differs across states and electricity distribution companies in India.
Net metering and gross metering are not the same
Net metering adjusts the power you export against the power you import. Gross metering works in a different way. Under gross metering, the electricity provider may buy all the solar power your system produces at a set rate, while you pay for the electricity your home consumes.
The available option depends on local rules, system size and the policy of your distribution company. Ask the provider which method applies before you place an order for a solar system.
How to get a net meter for your solar system
The process can vary by state, but it often includes these steps:
- Choose an approved solar installer.
- Apply to your electricity distribution company for grid connection and net metering.
- Submit documents such as identity proof, address proof and property details.
- Install the approved solar system after receiving permission.
- Allow the electricity company to inspect the system.
- Get the old meter replaced or upgraded with a bidirectional net meter.
The system must include safety devices such as an inverter, earthing and protection from excess current. The inverter changes the direct current from the panels into the alternating current used by home appliances and the grid.
Important points to check before installation
- Check the net metering rules in your state.
- Confirm the approved solar capacity for your connection.
- Ask about fixed charges and credit for extra exports.
- Check the expected time for approval and meter replacement.
- Review the warranty for panels, inverter and installation work.
- Read the first few bills to confirm import and export readings.
A net meter does not store electricity for later use. It records the movement of electricity between your home and the grid. For homes with frequent power cuts, an on-grid solar system may need a battery or backup inverter, since most grid-connected systems shut down during an outage to protect workers repairing the lines.
