Net Metering in Andhra Pradesh: How Your Meter Runs Backwards

People often say a solar meter runs backwards. A modern digital meter does something more precise: it records grid electricity used by your building and surplus solar electricity sent out from your roof in separate registers. Your bill then applies the approved net-metering rules to those readings.

During daylight, appliances can use solar power directly. If production exceeds what you are using, the remaining units go to the grid. At night or during a cloudy spell, you import electricity as usual. This is why the meter, grid approval and billing terms matter as much as the panels.

For a home on-grid system or a business rooftop plant, ask your DISCOM or installer which metering arrangement applies to your connection. The APSPDCL examples below show what to check in Andhra Pradesh.

What a bi-directional meter records

An ordinary meter measures power arriving from the grid. It is not suitable for recording an approved solar export. If surplus electricity flows through an unsuitable meter, that energy might not be credited correctly and could even be counted as consumption. The DISCOM must test and approve the replacement before grid synchronisation.

A bi-directional net meter gives you readings for each direction:

• Import register: Units your building takes from the grid at night, in poor sunlight or whenever demand exceeds solar output.
• Export register: Surplus solar units sent to the grid after your appliances have used what they need at that moment.
• Net calculation: The difference used in the billing example is Net Consumption = Import Units minus Export Units. Check how the current bill treats carried-forward credits as well.

Read imports, exports and banked units on your bill

APSPDCL serves the Tirupati, Chittoor, Nellore, Kadapa and Anantapur areas cited in this guide; APEPDCL serves other parts of the state. Under the APERC framework described here, the energy banking year runs from 1 April to 31 March. Current tariff orders and your connection agreement govern the detailed settlement. See our Tirupati solar page for the local project context.

Your DISCOM records the import and export readings for each billing cycle. Three examples show the difference between units used, units carried forward and the year-end settlement:

When you import more than you export

Suppose your home imports 450 units in a summer month and a 3 kW system exports 350 units. The example's net billed energy is 100 kWh, calculated as 450 minus 350. Energy charges apply to those 100 units under the relevant tariff, with fixed customer charges added. Do not assume a particular slab without checking the bill.

When you export more than you import

Suppose you import 250 units in December and export 350 units. The example leaves 100 surplus units. Energy charges for net consumption can fall to zero, while the minimum fixed connection charge may still apply. Those 100 units are banked for later use within the permitted period rather than disappearing at month end.

Settlement at the end of March

At the close of the 12-month banking period on 31 March, remaining units are settled under the applicable APERC order. For planning, use roughly ₹2.50 to ₹3.00 per unit as an indicative average power purchase cost, with the value credited against later bills. Confirm the current rate and credit treatment with your DISCOM; do not treat that estimate as a guaranteed payment.

Choose the metering arrangement that fits your connection

Net metering, gross metering and zero-export operation send different amounts of solar energy through the utility meter. The approved arrangement depends on connection category, plant size and current AP rules. Ask which application and meter your project needs before equipment is ordered.

For many homes, net metering can be valuable because exported units offset imported units at the applicable retail tariff. That does not make it automatically best for every roof. Compare daytime self-use, sanctioned load, meter rules and the current tariff. Larger plants have different approval questions; see our factory solar guide.

Follow the APSPDCL approval sequence

Net-meter approval protects the grid and confirms that the equipment is safe to connect. A PM Surya Ghar home application uses the national portal; business projects may have a different DISCOM route. Ask your installer to show the actual approval status at each stage.

1. Register and verify: For a home claim, enter the APSPDCL service connection or USC number and verify the applicant's Aadhaar-linked mobile on the portal.
2. Submit feasibility: The EPC partner provides the proposed kW capacity, inverter details and roof layout. APSPDCL checks the local distribution transformer, or DTR, and available export capacity.
3. Receive clearance: Allow roughly 5 to 10 working days as an indicative feasibility window. Wait for the actual DISCOM approval before construction; the status determines the capacity you may install.
4. Install the plant: Ray2Volt fits modules and inverter to the approved design. For a subsidised home project, the modules must meet ALMM and DCR requirements.
5. Submit completion records: The installer uploads the Work Completion Report, inverter test documents and earthing results. The bi-directional meter goes to APSPDCL's Meter Relay Testing division for calibration.
6. Complete joint inspection: The APSPDCL Assistant Executive Engineer checks the site, the approved meter replaces the old one, and the plant is synchronised with the grid.
7. Record commissioning: The signed Joint Inspection Report and Commissioning Certificate are uploaded. For an eligible PM Surya Ghar home, these records support the later DBT subsidy release to the verified bank account.

Our guide to applying for PM Surya Ghar covers the documents a homeowner needs at each stage. Keep your own copies of the approval, meter test and commissioning certificate.

Safety checks before the meter is fitted

The DISCOM checks more than the meter display. The inverter, disconnects and earthing must let utility crews isolate the plant safely. Have your installer show the test records, not just a brochure saying the equipment is grid-ready.

• Anti-islanding protection: The grid-interactive inverter must stop feeding a failed grid. For a voltage or frequency failure, check the installed model's test certificate for the cited disconnection limit of 2 seconds under IEEE 1547 and IEC 62116.
• Earthing and lightning protection: Separate protection for DC surge paths, AC equipment and the lightning arrester helps limit fault and surge risk. Have the resistance measured and recorded before inspection.
• Accessible isolation: A lockable external AC disconnect near the meter lets DISCOM staff isolate the solar plant during line work. Its position should be shown on the submitted single-line drawing.

Avoid three common commissioning delays

In local applications, these issues can cause extra visits or a revised submission. Check them while the design can still be changed.

Starting work before feasibility approval

A proposal or a portal acknowledgement does not reserve grid capacity. If the transformer cannot accept the requested export, APSPDCL may require a smaller system or a different arrangement. Wait for written feasibility clearance before mounting panels.

Proposing more than the sanctioned load

The proposed solar capacity must fit the approved load under the applicable APSPDCL rules. For example, a requested 5 kW plant with a 3 kW single-phase domestic connection calls for a load enhancement and possibly three-phase conversion before meter approval. Start with your bill and our guide to sizing a solar system, then confirm the DISCOM requirement.

Buying a meter before checking approval

The meter must meet the DISCOM's approved model and DLMS/COSEM communication requirements and pass testing. An unapproved unit can delay the site visit. Ray2Volt sources utility-approved meters and coordinates the lab check; ask who is responsible for procurement in your contract.

For roof conditions and weather in this service area, read our Tirupati and Srikalahasti solar guide. Generation estimates still need an audit of your own site.

Frequently asked questions

Net-metering tariffs and procedures are indicative and can change under APERC and DISCOM orders. PM Surya Ghar currently runs to 31 March 2027; confirm your own eligibility and the current export settlement terms before applying. Ray2Volt provides engineering and liaison support, not tax or investment advice.

Ray2Volt Solar Private Limited

We design, install, and service rooftop solar for homes and businesses across Tirupati district and Andhra Pradesh, from PM Surya Ghar residential systems to commercial and industrial plants. Every enquiry starts with a free power audit.