Your Head Contractor Wants Your Emissions Data: Scope 3 Requests for AU Construction, EPC and Solar Subcontractors (2026)

Oct 3

4 min read

Updated: Oct 7

If you build, install or maintain for a listed company, a tier-one builder, a utility or a large developer, expect a new kind of request in your inbox this financial year: a supplier questionnaire asking for your greenhouse gas emissions, your fuel and electricity use, and sometimes your climate targets.

It is not a fad and it is not going away. Australia's mandatory climate-related financial reporting regime is now in its second wave, and the companies at the top of your supply chain need numbers from the businesses underneath them. This guide explains why the requests are arriving now, what you are actually being asked for, and how to answer without hiring a sustainability team.

Why the requests are arriving now

Since 1 January 2025, large Australian entities have had to include climate-related financial disclosures in their annual reports under the Australian Sustainability Reporting Standards (AASB S2). The regime phases in by size:

Group 1 (the largest entities, broadly two of: $500m+ revenue, $1b+ gross assets, 500+ employees, or large NGER reporters) started with financial years beginning on or after 1 January 2025. For a 30 June year-end, that was FY26.
Group 2 (broadly two of: $200m+ revenue, $500m+ gross assets, 250+ employees, plus other NGER reporters) starts with financial years beginning on or after 1 July 2026. For a 30 June year-end, that is the year we are in now.
Group 3 (currently two of: $50m+ revenue, $25m+ gross assets, 100+ employees) starts from 1 July 2027. The 2026-27 Budget proposed lifting the Group 3 revenue and asset thresholds to $100m and $50m. Check where that proposal stands before you assume you are in or out.

Here is the part that matters for subcontractors. Reporting entities must disclose Scope 3 emissions, the emissions in their value chain, from their second reporting year. For a Group 1 company with a 30 June year-end, the second year started on 1 July 2026. Your emissions are part of their Scope 3. So they are asking you.

What you are actually being asked for

Most supplier questionnaires boil down to the same handful of questions:

Your Scope 1 emissions. Direct emissions from fuel you burn: diesel in plant and generators, petrol in utes, LPG, refrigerant top-ups.
Your Scope 2 emissions. Indirect emissions from the electricity you buy for your yard, office and workshop.
Activity data behind those numbers. Litres of fuel, kWh of electricity, sometimes kilometres travelled or tonnes of waste.
An allocation to their project. What share of your emissions relates to work done for them this year.
Targets and policies. Whether you have a reduction target, a renewable electricity plan, or anything else they can reference.

You are not usually being asked for your own Scope 3, a full sustainability report or third-party assurance. If a questionnaire asks for those, ask what they will actually use. Most heads of contract are happy to take a reasonable, documented estimate.

The good news: your accounting system already holds most of the data

Scope 1 and Scope 2 for a typical construction, EPC or solar subcontractor come mostly from three ledgers you already keep for BAS:

Fuel. Fuel card statements and fuel expense accounts give you litres by fuel type. If you claim fuel tax credits, you already track litres for eligible activities.
Electricity. Retailer bills give you kWh by site. Twelve bills per site is all you need.
Refrigerants and gases. Usually small, but trades with refrigerated vans or HVAC work should keep service records.

Multiply each activity by the current National Greenhouse Accounts emission factors published by the Department of Climate Change, Energy, the Environment and Water, and you have a defensible Scope 1 and Scope 2 figure. For most small and mid-sized operators, this is a spreadsheet, not a software project.

A five-step process we use with clients

Pick your period. Use your financial year so the numbers reconcile to your accounts.
Map the accounts. Tag the general ledger accounts that hold fuel, electricity and gas spend, and make sure fuel cards record litres, not just dollars.
Calculate and document. Apply the National Greenhouse Accounts factors and keep a one-page method note: sources, factors used, and any estimates.
Allocate to clients. Allocate emissions to each client by revenue or labour hours on their jobs. Revenue is simplest and most clients accept it; say which method you used.
Answer once, reuse often. Keep a standard response pack so the next questionnaire takes an hour, not a week.

Why this is a commercial issue, not just compliance

Tier-one builders and large energy developers are starting to score suppliers on climate data. A subcontractor who can answer quickly and credibly looks lower-risk at tender. One who cannot may simply not be asked back. For solar installers and renewables contractors, a clean emissions number is also a selling point you can put in your capability statement.

There is a finance-function angle too. If your fuel card data does not show litres, or electricity is buried in a general overheads account, the problem is not your climate maturity. It is your chart of accounts. Fixing it improves job costing at the same time.

Where TechEdge fits

We are a CPA-led outsourced finance team for Australian construction, EPC, solar, renewables and carbon businesses. We set up the ledger structure, calculate Scope 1 and Scope 2 from your existing records, and build the response pack you send to head contractors, as part of a Financial Controller or Head of Finance engagement.