Sustainability and energy in Indian factories: grid, solar and the reporting chain

Energy comes before the badge

A sustainability questionnaire usually asks for a policy, a target and a number. The policy is easy to write and the target is easy to set. The number is where programmes fail, because it depends on metering, on a boundary and on a calculation that the supplier may never have done.

For most Indian metal and electrical factories, the dominant operational emission is purchased electricity. Presses, compressors, furnaces, plating rectifiers, chillers and lighting all draw from the same supply. Fuel for heat treatment, paint drying or generators adds a smaller but significant line. Transport and purchased materials sit outside the operational boundary but often dwarf both.

Reading the Indian grid

India's grid is improving but remains coal dominated. The Central Electricity Authority publishes a carbon dioxide baseline database that gives an emission factor for the grid, and the figure has been falling as renewable capacity grows. The national average hides a wide spread between states with hydro, nuclear or wind and states that depend on coal.

For a supplier, the practical consequence is that location and supply contract matter. A plant in a state with a cleaner generation mix has a lower scope two figure for the same consumption. A plant that buys renewable power through open access or a group captive arrangement can report a lower factor, provided the contractual chain supports the claim.

Solar, open access and the contract behind the claim

Rooftop solar is the simplest intervention to verify. The panels sit on the supplier's roof, the generation meter is visible, and the share consumed on site can be calculated against the load profile. The limitation is roof area and the match between generation and shift patterns. A plant that runs at night consumes little of its own solar output.

Open access allows a consumer to buy power from a generator elsewhere and wheel it across the grid. It can be cheaper and cleaner than the local tariff, but it comes with transmission charges, cross subsidy surcharge, banking rules and a contract term. The carbon claim depends on the contractual instruments and on how the units are settled.

The efficiency measures that pay first

Compressed air is usually the quickest win. Leaks, oversized compressors, unnecessary pressure and poor control waste a large share of the energy that goes into the system. A leak survey and a pressure reduction cost little and show up on the meter within weeks.

Motors and drives come next. Replacing an old motor with a higher efficiency unit, or adding a variable speed drive to a pump or fan, cuts consumption in proportion to the load profile.

Thermal processes are harder. Furnace insulation, burner tuning, heat recovery and loading practice all matter, but the capital is larger and the interruption is longer. Plating lines offer a different set of wins: rectifier efficiency, rinse water heating, evaporation control and the power factor of the installation.

• Compressed air leak survey and pressure set point
• High efficiency motors and variable speed drives
• Furnace insulation, door discipline and burner tuning
• Plating rectifier efficiency and rinse heating
• Power factor correction and demand management
• Chiller set points and cooling water recovery
• Sub metering by department or by process

Measuring and baselining

A carbon number without a baseline is a snapshot that cannot be managed. The baseline needs a period, a boundary and a method. A full year is better than a quarter because it captures seasonality, but a shorter period can work if the production mix is stable and the reading is normalised.

Normalise to output. Energy per kilogram of good parts, or energy per part, lets a buyer compare months with different volumes and lets a supplier show that a reduction is real rather than the result of a quiet order book. The normalisation also exposes the months when a plant is inefficient because it is running at low load.

Sub metering is the single most useful investment. A plant that knows what the compressor, the plating line and the press shop each consume can target the biggest load.

The reporting chain a buyer actually needs

European buyers increasingly ask for product level figures, driven by customer requirements and by regulation such as the carbon border adjustment mechanism for certain goods. The direction is clear: the figure has to be traceable to the production route.

In India, larger listed companies report under the business responsibility and sustainability reporting framework, but most small and medium suppliers do not report publicly.

Ask for scope one and scope two separately, the grid factor and its year, the meter readings or utility bills behind the total, the production volume used for normalisation, and the boundary. Then ask what changed since the baseline.

1. 01

   Boundary

   State which site, which processes and which fuels are included.

2. 02

   Meter data

   Collect utility bills or meter readings for a full period.

3. 03

   Factor

   Name the grid factor, its source and its year.

4. 04

   Normalise

   Divide by output so the figure can be compared over time.

5. 05

   Report

   Separate scope one and scope two and state the method.

6. 06

   Verify

   Check the arithmetic and the source documents before using the number.

The limits of a supplier claim

A renewable claim can be legitimate and still be small. For illustration, if a plant meets a tenth of its demand from rooftop solar, the scope two reduction is a tenth, not a transformation. The rest of the footprint sits in purchased material, which is often the largest part of a product footprint and the hardest to trace.

Material is the next frontier. Copper, aluminium and steel carry embodied carbon from mining, refining and casting. A supplier that buys recycled copper or aluminium with a verified content can offer a lower product footprint, but the claim depends on the chain of custody and on the alloy.

What to put in the supplier conversation

Start with a request for data, not a request for a policy. Ask for twelve months of electricity bills, the fuel used by process, the production volume and the grid factor.

Then agree a reduction plan with a baseline and a review date. A leak survey, a motor replacement and a solar feasibility study are concrete steps with dates and owners.

Finally, connect the reporting requirement to the commercial relationship. If a buyer needs a product level figure for a regulated market, say so at the RFQ stage and say what data will be required each year.