# How much electricity does a CNC turret punch save over a conventional punch in a Bangalore machine tools unit?

Canonical: https://senseible.earth/answers/bangalore-sheet-metal-cnc-turret-punch-kwh

Per tonne, a lot; on the bill, little. BEE's SAMEEEKSHA project report for the Bangalore machine tools cluster cuts specific energy from 975 to 575 kWh per tonne with a CNC turret punch, while output rises from 130.5 to 228.375 t a year. Total power use barely moves; the gain is more tonnes for the same kWh.

## What the report assumes

- Conventional turret punch: 975 kWh per tonne, 130.5 t a year.
- CNC turret punch: 575 kWh per tonne, with output 1.75 times higher, 228.375 t a year.
- Saving counted: 400 kWh per tonne on 228.375 t; the report puts the CO2 cut at 68.51 t a year.
- The machine punches 6 mm mild steel or 4 mm stainless, on sheets up to 1,270 x 3,000 mm, without re-tooling.

## The cluster

About 100 machine tool units in Bangalore, making from 1.5 t to 1,050 t a year. BEE audited 30 of them, 10 in detail. Grid electricity is their main energy.

## What to tell a buyer

Report the change as kWh and CO2 per tonne, not as a cut in total emissions. Your total can stay flat or rise with output while each part gets cleaner, which is what a buyer's product footprint uses.

## Worked from the report's figures

- Before: 975 kWh x 130.5 t = 127,238 kWh a year
- After: 575 kWh x 228.375 t = 131,316 kWh a year, slightly more in total
- Counted saving: 400 x 228.375 = 91,350 kWh; at 0.675 kg/kWh (CEA, FY 2025-26) = 61.7 t CO2
- The report's 68.51 t implies about 0.75 kg/kWh, an older grid factor
- Per tonne: 975 x 0.675 = 658 kg CO2 before, 575 x 0.675 = 388 kg after

## What Senseible does here

Senseible reads your monthly electricity bills at 0.675 kg CO2 per kWh for FY 2025-26; add your despatched tonnes and the per-tonne figure before and after a new machine follows from your own records.

- [Your MSME carbon number](https://senseible.earth/msme-carbon-number)
- [Bangalore machine tool units: power saving](https://senseible.earth/answers/bangalore-machine-tool-units-grid-power-saving)
- [CNC lathe replacing conventional lathes](https://senseible.earth/answers/cnc-lathe-replacing-conventional-lathes-kwh)

Sources: [BEE SME programme (SAMEEEKSHA), Detailed project report: CNC turret punch, Bangalore machine tools cluster](https://sameeeksha.org/pdf/dpr/Bangalore_machine_tools_cluster/Conventional_turret_punch_machine_with_CNC_turret_punch_machine_BNG_MTC.pdf), [CEA CO2 Baseline Database User Guide, version 22.0](https://cea.nic.in/api/cdm-report-version/view-pdf/en/82)

Last reviewed 2026-11-03.