☀️ Solar Net Metering & Billing

TNEB Solar Bill Calculator 2026

Calculate your Net Metering bill, solar generation credits, Feed-in tariffs, and network infrastructure charges instantly based on TANGEDCO’s latest solar utility rules.

Calculates Net Metering & Net Billing Mechanisms
Auto-estimates Network Charges (₹1.27/unit LT Connection)
Compares Solar Generation Exports & Feed-in Tariffs
100% Updated with the Newest 2026 TANGEDCO Orders
TNEB Solar Calculator
Domestic (Home) Commercial (LT) Industrial (LT-III-B / HT)
Net Metering Net Billing Gross Metering

What is the TNEB Solar Bill Calculator?

The adoption of rooftop solar systems in Tamil Nadu has grown rapidly. TANGEDCO has established specific billing frameworks to manage solar power grid-exports and imports. The TNEB Solar Bill Calculator 2026 is a specialized tool built to calculate energy bill adjustments, net billing credits, and network infrastructure fees instantly.

Calculations for rooftop solar systems differ based on whether you are a residential consumer or a business. Residential accounts rely on a unit-based adjustment system known as Net Metering, whereas commercial and industrial connections use a monetary-credit adjustment system known as Net Billing. Our calculator handles both methods accurately according to the latest TNERC directives.

Understanding TNEB Solar Billing Mechanisms

To understand how TNEB calculates your final bill, you must know which solar billing mechanism is applicable to your connection category:

1. Net Metering (For Domestic Consumers)

Net Metering is a unit-to-unit subtraction system designed specifically for residential houses and apartments under LT Tariff I-A.

  • How it works: The total units generated by your solar system (Export Units) are subtracted directly from the total units drawn from the grid (Import Units).
  • Net Units: You are only billed for the net consumption (Import – Export). If you import 400 units and export 300 units, you only pay for 100 net units.
  • Surplus Carry Forward: If you export more than you import (e.g., 400 exported vs. 300 imported), your net energy charges are ₹0, and the remaining 100 units are carried forward to your next billing cycle as a credit.

2. Net Billing (For Commercial & Industrial Consumers)

Net Billing applies to commercial (LT-V), industrial (LT-III-B), and HT connections. In this system, units are not directly subtracted:

  • How it works: Your consumed energy (Import Units) is billed at the standard commercial or industrial flat/telescopic rates. Separately, TANGEDCO buys your generated energy (Export Units) at a fixed **Feed-in Tariff** rate set by the government.
  • Monetary Credits: The monetary value of your exports is credited against your total import bill. If the import bill is ₹5,000 and your export credit is ₹3,000, your net payable bill is ₹2,000.
  • Feed-in Tariff Rates (2026): TANGEDCO pays a feed-in tariff based on your solar system capacity:
        – Systems ≤ 10 kW: ₹3.61 per unit
        – Systems 11 to 150 kW: ₹3.37 per unit
        – Systems ≥ 151 kW: ₹3.10 per unit

What are TNEB Solar Network Charges?

Even when you generate your own solar energy, you still utilize TANGEDCO’s electrical grid infrastructure, poles, and transformers to export surplus power and maintain grid stability. To fund this maintenance, TNEB levies **Network Charges** (also known as wheeling charges) on every unit generated by your solar system.

The network charge rates set by TNERC are:
• Low Tension (LT) Connections: ₹1.27 per unit of solar energy generated.
• High Tension (HT) Connections: ₹0.83 per unit of solar energy generated.
Note: Residential solar setups up to 10 kW may receive partial waivers on network charges depending on current TNERC policy updates.

Step-by-Step Guide on How to Use the Solar Calculator

Calculating solar net billing involves factoring in import tariffs, feed-in rates, capacity multipliers, and network fees. Follow these simple steps to calculate your bill:

01

Select Consumer Category

Choose “Domestic (Home)” if the system is installed on a residential property, or “Commercial” / “Industrial” for business lines.

02

Choose Billing Mechanism

Select “Net Metering” (residential unit subtraction) or “Net Billing” (monetary credits based on feed-in rates).

03

Enter Plant & Unit Details

Input your solar plant capacity (kW), import units drawn from TNEB, and export units sent back to the grid.

04

Calculate & Review

Click “Calculate Solar Bill” to display a detailed breakdown of grid import charges, solar export credits, network charges, and the final net bill.

Check Our Other Free TNEB Utilities

Check your bills or perform tariff assessments instantly using our specialized free tool variants:

Domestic Calculator

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Commercial Calculator

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Shutdown Tomorrow

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Chennai Power Cuts

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Frequently Asked Questions (FAQ)

1. What is the difference between Net Metering and Net Billing?

Net Metering is a unit-subtraction system designed for residential connections. Exported units are subtracted directly from imported units. Net Billing is a monetary-credit system designed for commercial/industrial connections. Consumed units are billed at commercial slab rates, while exported units are credited at TANGEDCO’s fixed feed-in rate (₹3.61/unit up to 10 kW).

2. What are network charges, and why do I have to pay them?

Network charges are wheeling fees charged by TANGEDCO for utilizing the state grid infrastructure to export surplus power and draw electricity when solar generation is low. For low tension connections, it is set at ₹1.27 per unit generated.

3. Can I carry forward surplus solar energy credits to the next month?

Yes. If your solar export exceeds your grid consumption, the surplus units (under Net Metering) or monetary credits (under Net Billing) are carried forward to your next billing cycle. They will be adjusted against your future electricity bills.

4. What is the maximum solar plant capacity I can install for my property?

As per TANGEDCO rooftop solar guidelines, you can install a solar plant capacity up to **100% of your sanctioned load** capacity. For instance, if your sanctioned load is 5 kW, your solar plant capacity cannot exceed 5 kW.

5. Are there any government subsidies available for rooftop solar in Tamil Nadu?

Yes, the central government offers subsidies for residential rooftop solar installations under the PM-Surya Ghar: Muft Bijli Yojana. Subsidies range from ₹30,000 to ₹78,000 based on capacity (1kW, 2kW, or 3kW+ systems), provided the installation is done by an empanelled vendor.

6. Does the solar calculator include fixed demand charges for commercial connections?

No, this solar calculator focuses on estimating your energy charges, solar export credits, and network charges. If your connection is commercial or industrial, you must add the standard fixed demand charges (based on sanctioned load) to get your final bill. You can check these fixed charges using our Commercial EB Calculator.

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