# Can I use smart meter or sub-meter data instead of electricity bills for carbon reporting?

Canonical: https://senseible.earth/answers/smart-meter-data-vs-bills-for-carbon-reporting

Yes for a discom smart meter, because it is the revenue meter your bill comes from. Use your own sub-meters to split electricity between lines or products, not to set the total. The site total should match the discom meter, and any gap between the sub-meters and the bill needs to be explained.

## Discom smart meters are billing-grade

Smart meters fitted under the Revamped Distribution Sector Scheme replace the discom's revenue meter. Their readings are what you pay for, so they are as good as a bill for Scope 2. On a prepaid smart meter with no monthly bill, the discom's consumption statement becomes your evidence; the prepaid page linked below sets out how to get it.

## Your own sub-meters are for splitting, not totals

- Sub-meters are often not calibrated to billing accuracy, and they miss losses, lighting and loads nobody metered.
- Use them to allocate the bill to production lines, buildings or tenants, or to support a product footprint.
- Keep calibration or test records, and note any meter replaced during the year.

## Reconcile before you report

1. Take the total kWh from the discom meter for each month.
2. Add up the sub-meters for the same period.
3. Treat the difference as losses and unmetered load, and spread it in proportion to each sub-meter, or show it as a separate line.
4. If the gap is large, look for a faulty sub-meter or an unmetered load before you report.

## What an auditor will ask

Auditors trace the reported total to an external document, which is the discom bill or statement. Interval data from a sub-meter or an energy monitoring system is useful supporting evidence, but on its own it is your own record, not the supplier's. The GHG Protocol and ISO 14064-1 both expect you to describe data sources and manage this kind of uncertainty.

## Worked example: splitting one month across lines

- Discom meter: 120,000 kWh; sub-meters add up to 112,800 kWh
- Gap: 7,200 kWh (6% of the bill), spread in proportion
- Line A sub-meter: 48,000 kWh, share 48,000 / 112,800 = 42.55%
- Line A allocated: 48,000 / 112,800 x 120,000 = 51,064 kWh
- Line A Scope 2: 51,064 x 0.710 = 36,255 kg CO2
- Site Scope 2: 120,000 x 0.710 = 85,200 kg CO2

Factor: 0.710 kg CO2 per kWh, CEA CO2 Baseline Database, version 21.0, location-based.

## What Senseible does here

Senseible reads your electricity bills for the site total and applies the CEA grid factor. Meter and sub-meter feeds can be added too, set up with the Senseible team for each customer, so the split by line sits next to the billed total.

- [Smart prepaid meter with no bill](https://senseible.earth/answers/smart-prepaid-meter-no-bill-scope-2-data)
- [Sub-metered electricity in a rented unit](https://senseible.earth/answers/sub-metered-electricity-rented-unit)
- [Allocating factory electricity to products](https://senseible.earth/answers/how-to-allocate-factory-electricity-to-products)
- [Do I need smart meters for Scope 2?](https://senseible.earth/answers/do-i-need-smart-meters-for-carbon-reporting)

Sources: [GHG Protocol Corporate Standard, Chapters 6 and 7](https://ghgprotocol.org/corporate-standard), [ISO 14064-1:2018, Greenhouse gases, organization level (iso.org)](https://www.iso.org), [Ministry of Power, Revamped Distribution Sector Scheme (powermin.gov.in)](https://powermin.gov.in)

Last reviewed 2026-10-16.