Solar net metering: how to sell electricity back to the grid

Net metering has changed the economics of rooftop solar in Bangladesh. Before SREDA's 2018 net-metering guideline, a home solar array could only offset its own load — anything unused was wasted. After the guideline, your meter can run backwards. Extra generation is exported to the grid, and the distribution company credits your next bill for those units. Eight years on the programme is fairly mature. The application path is now clear, if you know what to ask for.

How net metering actually works

In a net-metered system a bi-directional meter records two numbers: import (units taken from the grid) and export (units sent back). The bill is calculated on the net figure. 300 units imported and 250 exported means you pay your tariff slab on 50 units. If you export more than you import in a cycle, the extra becomes a credit on the next bill. At the end of the fiscal year (June in Bangladesh) any unused credit is paid out by the utility at the bulk supply rate, which is much lower than retail. The system is designed to incentivise self-consumption over banking.

Eligibility and limits

The 2018 guideline, amended in 2022 and again in 2024, permits:

• Residential, commercial, and industrial — all category connections (LT-A residential, LT-E commercial, LT-C1 small industry, MT-3 industry and HT-3 industry, for example).
• System capacity up to 70% of your sanctioned load. A 5 kW load home can install up to 3.5 kW of panels.
• AC-side connection through an approved string inverter that meets BERC-published interconnection standards, with automatic islanding protection.

If you want more than 70% of load, you'll need to apply for a sanctioned-load upgrade first — itself a three-week process. Build this into the plan before ordering panels.

Step-by-step application process

1. Pick an empanelled vendor

SREDA maintains a list of empanelled rooftop solar EPC contractors. You don't strictly have to use a name on the list, but going outside it triggers much heavier utility scrutiny, and your inverter brand must be on the separately approved list. Empanelled vendors significantly shorten the approval timeline.

2. Submit the joint application

The application goes to your distribution company (DESCO, DPDC, BPDB, NESCO, BREB) with a copy to SREDA. You'll need:

• The latest electricity bill
• National ID of the connection holder
• A site map and a roof load-bearing certificate
• A single-line diagram of the proposed system
• Inverter and panel datasheets

3. Technical inspection and bi-directional meter swap

The distribution company sends an engineer to inspect the installation and verify that the inverter passes the islanding test. On clearance, your existing one-way meter is swapped for a bi-directional meter, usually free of charge — though some zones charge a small swap fee. The final reading on the old meter is recorded on the closing bill so there's no overlap.

4. The net metering agreement

You sign a tripartite agreement with the distribution company and SREDA. The agreement is open-ended (no fixed term) and either party can terminate with 30 days' notice. There is no feed-in tariff: surplus at year-end is paid only at the bulk supply rate.

What a typical 5 kW rooftop earns

A properly installed 5 kW system in Dhaka generates an average of 500–620 kWh a month. Call it 6,500 kWh a year. A family that consumes roughly that amount over the year zeros itself out effectively, paying only demand charge, meter rent, and VAT on those lines.

For an LT-A family using 250 units a month, energy cost is 75 × 5.26 + 125 × 8.50 + 50 × 9.10 = ৳1,912. With 5 kW sanctioned load, 5% VAT and an illustrative ৳30 meter rent, the bill is ৳2,258.10. Fully offsetting that energy saves ৳1,912 × 1.05 × 12 = ৳24,091.20 a year; fixed charges remain. At an assumed turnkey cost of ৳3.5–4.0 lakh, simple payback is about 15–17 years, before maintenance, inverter replacement or any year-end surplus payout. Confirm the load limit for a 5 kW system before ordering. Use the calculator to model your post-solar bill and see which slab you'd land in.

Mistakes to avoid

• Over-sizing. If you install more than your load, most of your generation goes to the grid at bulk rates, not retail. Aim for 70–90% of annual usage, not over 100%.
• South-east shading. In Dhaka, a 10% shading loss reduces annual generation by roughly 8%. Observe roof shading across a full day before signing the contract.
• Wrong inverter. Hybrid inverters with battery backup are popular, but most are not net-metering certified. Verify the inverter is on the SREDA-approved list before buying.
• Skipping the load-bearing certificate. Structural engineer sign-off is mandatory, and many older RCC roofs don't pass without minor reinforcement.

What to ask the distributor

Before signing the contract, call your zonal office and confirm:

• Current bi-directional meter swap fee, if any
• Whether your sanctioned load supports your target system size
• The bulk rate at which year-end surplus will be paid
• The expected timeline from application to commissioning

Two of these answers — the bulk rate and the load limit — directly change the financial model. Get them in writing.

Maintenance and real-world lifespan

Solar maintenance is usually light, but not zero. A short routine should include:

• Panel cleaning. In Dhaka's dust, washing panels once every six months keeps generation about 5–8% higher. The monsoon does some of this work for you, so the dry season matters most.
• Inverter monitoring. Most modern inverters have a Wi-Fi/cloud app. One minute a week looking at the daily generation graph catches problems on day one.
• Inverter replacement. After 8–12 years the inverter needs replacing. That's about 15–20% of the original CapEx. Budget for it in the investment model upfront.

Net metering is one of the few policy levers in Bangladesh that lets a family cut both its own bill and the country's fuel import dependency at the same time. The application process is real work, but finite: most rooftops are commissioned within 60 days of application. Combine it with the bill-reduction tactics covered elsewhere on this site — especially our AC efficiency and 7 causes of bill spikes posts — and the savings compound. The math works. The paperwork is the hard part.