How to Track Energy Consumption for ESG Reporting: A Practical Guide

Nearly every ESG questionnaire asks about energy consumption. Customers want to know how much electricity and fuel you use, whether you've set reduction targets, and what your carbon footprint is. For many small and mid-sized suppliers, this is the first time anyone has asked to quantify energy use beyond just paying the bills.

The good news: you already have the data. You just need to know where to find it, what units to use, and how to organize it for reporting.

Where to Find Your Energy Data

Electricity: Your utility bills contain monthly consumption in kilowatt-hours (kWh). If you have multiple sites or meters, you'll have separate bills for each. Log into your utility provider's online portal—most allow you to download 12-24 months of consumption data as a CSV file, which saves manual data entry.

Natural gas: Also on your utility bills, but the units vary by country. In the UK, gas is billed in cubic meters (m³) or sometimes kWh. In the US, it's typically therms or CCF (hundred cubic feet). You'll need to note which unit your supplier uses.

Heating oil or propane: Check delivery invoices if you use oil or LPG for heating. These are typically measured in liters or gallons. You'll need all delivery receipts for the reporting period.

Fleet fuel: If you operate company vehicles, pull fuel card statements or petrol receipts. Track diesel and petrol separately—they have different carbon emission factors.

Renewable energy: If you generate solar power or purchase renewable electricity, this still counts as energy consumption. Note it separately so you can report both total energy use and renewable percentage.

Understanding Energy Units: kWh vs MWh

Energy consumption is typically measured in kilowatt-hours (kWh) or megawatt-hours (MWh).

1 kWh = 1,000 watt-hours (enough to power a 100-watt bulb for 10 hours)
1 MWh = 1,000 kWh

For ESG reporting, most SMEs report in MWh for consistency across electricity, gas, and fuels. If your annual electricity consumption is 450,000 kWh, that's 450 MWh.

Natural gas conversions: If your gas is billed in cubic meters, you need to convert to kWh or MWh for reporting:

In the UK: 1 m³ of natural gas ≈ 11.1 kWh (this varies slightly by gas composition; check your bill for the exact conversion factor)
In the US: 1 therm = 29.3 kWh; 1 CCF ≈ 103.7 kWh

Fuel conversions: Liquid fuels like diesel and petrol need conversion to energy units:

1 liter of diesel ≈ 10.0 kWh
1 liter of petrol ≈ 9.0 kWh
1 liter of heating oil ≈ 10.0 kWh

These are approximations; exact values depend on fuel composition, but they're accurate enough for ESG reporting.

Setting Up a Simple Monthly Tracking Spreadsheet

You don't need complex software. A basic Excel or Google Sheets tracker works perfectly well for most SMEs.

Create columns for:

Month
Electricity (kWh)
Natural gas (m³ or therms)
Natural gas (kWh) — converted
Diesel (liters)
Diesel (kWh) — converted
Petrol (liters)
Petrol (kWh) — converted
Total energy consumption (MWh)

Add a row at the bottom for annual totals. This gives you the data you need for 90% of ESG questionnaires.

Practical tip: Assign someone to update this monthly—don't wait until year-end. It's much easier to track down a missing utility bill in February than to reconstruct 12 months of data in December when a customer questionnaire arrives.

Converting Energy Consumption to CO2 Emissions

Many customers want to know your carbon footprint, not just energy consumption. To convert energy use to CO2 emissions, you multiply by an emission factor.

Emission factors vary by country and energy source. Here are approximate figures for 2026:

Electricity:

UK grid electricity: ~0.22 kg CO2e per kWh
US grid electricity (average): ~0.40 kg CO2e per kWh
EU grid electricity (average): ~0.28 kg CO2e per kWh

Natural gas: ~0.18 kg CO2e per kWh

Diesel: ~2.7 kg CO2e per liter

Petrol: ~2.3 kg CO2e per liter

Check your national emissions database for exact factors—they're updated annually. In the UK, use BEIS (now DESNZ) conversion factors. In the US, use EPA emission factors.

Example calculation: A manufacturer uses 450 MWh of electricity annually in the UK.

450,000 kWh × 0.22 kg CO2e/kWh = 99,000 kg CO2e
= 99 tonnes CO2e

Add up emissions from all energy sources to get total Scope 1 (direct fuel combustion) and Scope 2 (purchased electricity) emissions.

What About Renewable Energy?

If you purchase certified renewable electricity or generate your own solar power, you can report lower Scope 2 emissions. There are two methods:

Location-based method: Uses the average grid emission factor (as above).

Market-based method: Uses emission factors based on your contractual purchases. If you buy 100% renewable electricity with REGOs (UK) or RECs (US), your electricity emission factor is effectively zero.

Most SMEs report using the location-based method unless they've made significant renewable investments. Be consistent year-over-year in whichever method you choose.

Common Mistakes to Avoid

Mixing units: Don't report electricity in kWh and gas in m³ without conversion. Convert everything to the same energy unit (MWh).

Forgetting fleet fuel: Many suppliers only track facility energy and forget vehicle fuel. If you're reporting Scope 1 emissions, fuel must be included.

Using old emission factors: Emission factors change annually as the electricity grid gets cleaner. Always use factors for the reporting year.

Not tracking monthly: Waiting until year-end to gather data is painful and error-prone. Monthly tracking takes 15 minutes; annual reconstruction takes days.

Reporting Energy Data in ESG Questionnaires

When customers ask for energy consumption, they typically want:

Total annual energy use (MWh)
Breakdown by source (electricity, gas, fuels)
Year-over-year change (%)
Any energy efficiency initiatives undertaken
Total Scope 1 and Scope 2 emissions (tonnes CO2e)

If you're completing multiple customer questionnaires, consider using ESG Passport to store your energy data centrally and auto-populate responses across different formats, saving hours of repetitive data entry.

Moving Beyond Tracking: Setting Reduction Targets

Once you have 2-3 years of baseline data, customers will expect to see reduction targets. A simple target might be "reduce electricity consumption by 10% by 2028 compared to 2025 baseline" or "reduce carbon emissions by 15% by 2030."

Even small changes add up: LED lighting, building insulation, equipment timers, vehicle route optimization, and equipment maintenance all reduce energy use and costs. The companies that succeed in ESG aren't necessarily those with the lowest starting point—they're the ones showing continuous improvement.

Final Thoughts

Tracking energy consumption for ESG reporting doesn't require sophisticated systems or consultants. Start with your utility bills, set up a simple spreadsheet, convert to consistent units, and update monthly. Within a year, you'll have robust data to answer customer questionnaires confidently and identify opportunities to reduce both costs and environmental impact.