How to Choose Carbon Accounting Software in...

Your CFO just told you to find carbon accounting software. You've got three months before ASRS Group 2 reporting starts, a shared drive full of utility bills nobody has touched, and a budget that won't stretch to a Big Four engagement. So you Google it. And every result on page one is a vendor ranking themselves first.

We build carbon accounting software. We're biased too. But our team spent 18 years inside enterprise data platforms at BHP, Rio Tinto, and Senex Energy before writing any product code. We've sat through NGER audits. We've watched companies sign contracts for platforms that couldn't read an AGL electricity bill. So this is the checklist we'd hand to a colleague before they evaluate anything, including us.

Here's the thing most buyers get wrong: they start with features and integrations. They should start with whether the software can actually handle the documents their business produces.

Start with the documents, not the dashboard

The hardest part of carbon accounting isn't the maths. Multiplying kilowatt-hours by an emission factor is arithmetic. The hard part is getting the kilowatt-hours out of a scanned PDF where the format changes every time your energy retailer redesigns their invoice.

Ask any vendor this question during a demo: "Can I upload a scanned fuel docket from a construction site, a multi-page AGL electricity bill, and a supplier invoice in PDF, and get emission calculations without manually entering anything?"

Most platforms will need you to extract the data yourself first, then upload a CSV or type numbers into a form. That's not automation. That's a spreadsheet with a login page.

What you actually want is a platform that reads the document itself. Not a template that expects data in column A and column B. A system that understands layout, context, and the relationships between fields on a messy real-world bill. When your retailer changes their format (and they will), you don't want to file a support ticket and wait for a template update.

At Carbonly, we built our AI document engine to handle eight file formats: PDF, CSV, Excel (including multi-sheet workbooks), Word, PowerPoint, RTF, and images including photos of meter readings taken on a phone. We process the document the way a human analyst would, understanding what the numbers mean in context, not just where they sit on the page. But regardless of which platform you choose, test it with your actual documents during the trial. Not their sample data. Yours. If it can't handle what your suppliers send you, the rest of the features don't matter.

NGER-native or bolted on?

This is the question that separates Australian-built platforms from global ones adapted for the local market. And the difference is bigger than most buyers realise.

NGER reporting requires per-facility tracking with specific activity codes aligned to the EERS (Energy and Emissions Reporting System). It requires NGA emission factors published annually by DCCEEW, which differ by state for grid electricity. Victoria's scope 2 factor (0.78 kg CO2-e/kWh) is nearly four times Tasmania's (0.20). Using a national average instead of state-specific factors can understate or overstate your emissions by 20% or more, depending on where your operations sit.

NGER also requires AR5 Global Warming Potential values for converting greenhouse gases to CO2-equivalent. AASB S2, by contrast, requires AR6. If your platform doesn't handle both, you'll end up maintaining parallel calculations or, worse, submitting inconsistent numbers to the Clean Energy Regulator and ASIC.

Global platforms built for US or European markets tend to bolt Australian requirements on as a regional module. That means NGA factors might lag behind the latest DCCEEW update. Facility-level tracking might not align with NGER's corporate group structure. Output formats might not map to what the Clean Energy Regulator actually expects.

When evaluating, ask specifically: "Which edition of NGA Factors does the platform currently use? How quickly do you update when DCCEEW publishes a new edition?" The 2025 NGA Factors were published with amendments for the 2025-26 reporting year, including updated scope 2 and 3 electricity factors and new scope 1 factors for hydrogen combustion. If a vendor can't tell you which edition they're running, that's your answer.

AASB S2 is not just emissions numbers

Here's where a lot of platforms fall short, and most buyers don't catch it until too late. AASB S2 mandatory climate reporting isn't only about calculating Scope 1 and 2 emissions. Group 2 entities (reporting from financial years starting 1 July 2026) need to disclose across four pillars: governance, strategy, risk management, and metrics and targets.

That means your software needs to support, or at least not obstruct, disclosures about how your board oversees climate risks, what transition plan you're working toward, how climate scenarios affect your financial position, and what targets you've set. Most carbon calculators handle the metrics pillar reasonably well. Very few help with the other three.

Under ASSA 5010, the assurance standard that applies to mandatory sustainability reports, Group 2 entities face limited assurance from Year 1 over governance disclosures, parts of strategy (specifically subparagraphs 9(a), 10(a), and 10(b) of AASB S2), and Scope 1 and 2 emissions. By Year 2, limited assurance expands to cover climate resilience assessments, scenario analysis, transition plans, risk management, Scope 3 emissions, and all metrics and targets. By Year 4, everything steps up to reasonable assurance.

So if you're buying software today, you need it to support the full AASB S2 disclosure structure, not just an emissions calculator. Ask during evaluation: "Can your platform generate or structure disclosures for all four AASB S2 pillars? Or only metrics?" If it's only metrics, you'll need a second system (or a consultant) for everything else. And that defeats the purpose.

Carbonly's reporting module generates outputs aligned to NGER, GHG Protocol, and AASB S2 disclosure structures, covering the quantitative and qualitative components that auditors need to see. We're not going to pretend governance disclosures are easy to automate. They aren't. But the platform should at least give you the structure, the prompts, and the evidence trail so you're not starting from a blank Word document.

How much manual work does it actually eliminate?

"Automated" is the most overused word in this market. Every vendor claims it. Few deliver it.

Here's what real automation looks like in carbon accounting: you upload a stack of utility bills, fuel dockets, or supplier invoices. The platform reads each document, extracts the relevant data (consumption, units, billing period, meter number, site), matches the extracted activity to the correct emission factor from a maintained database, runs quality checks for anomalies (did that small office in Parramatta really consume 2.4 million kWh last quarter?), and produces an auditable emission figure linked back to the source document. No manual data entry. No spreadsheet wrangling.

What "automated" often means in practice: you can connect your Xero or MYOB account and the platform estimates emissions from spend data. Or you upload a pre-formatted CSV and the platform applies factors. Both still require someone to prepare the data first. That someone is usually your sustainability analyst, spending 300 hours a year copying numbers from PDFs into templates.

When running a trial, count the clicks. Literally. Upload ten real documents and see how many manual steps sit between "upload" and "emission figure in a report." If you're still selecting emission factors from dropdown menus, typing consumption values, or manually matching line items to activity categories, the platform hasn't solved the actual problem.

We built Carbonly's 5-tier material matching system specifically to eliminate that manual matching step. It tries exact name matching against our material library first, then factor code matching, then alias matching, then fuzzy text similarity, and finally AI-assisted matching with confidence scores for human review. The system learns from your corrections over time, so matching accuracy improves the longer you use it. We're still refining how this works for edge cases (some construction materials have dozens of trade names for the same product), but the core pipeline handles the bulk of matching without human input.

The audit trail question your auditor will ask

ASSA 5010 requires assurance over your sustainability report from Year 1. For Group 2, that means limited assurance over governance, parts of strategy, and Scope 1 and 2 emissions for financial years starting July 2026. Your auditor will need to trace every reported number back through a chain: reported figure, to calculation method, to emission factor applied (and which edition), to extracted consumption value, to the original source document.

If your software can't produce that chain in a few clicks, you'll pay for it in assurance fees. Limited assurance for a mid-market company typically costs between $30,000 and $80,000. But that assumes the auditor receives clean, traceable data. When they can't trace a figure, they do the tracing themselves, at $300 to $500 per hour. An extra 40 hours of auditor time reconstructing your evidence chain adds $12,000 to $20,000 to your bill. Every year.

Ask every vendor: "Can you show me the complete audit trail from a reported Scope 2 figure back to the original electricity bill, including which NGA Factor edition was applied, who entered or approved the data, and when?" Then actually watch them do it. In the demo, not in a slide deck.

Carbonly logs every step: who uploaded the document, what was extracted, which emission factor was matched (and at what confidence level), who reviewed and approved it, and when the calculation was finalised. That full chain is exportable and designed for the assurance process under ASSA 5010. We think audit trail depth is one of the most undervalued features in this category, because you don't feel the pain of a weak audit trail until your first assurance engagement, when it's too late to fix.

Multi-site, multi-project, and joint ventures

If you operate across a single site, most platforms will work fine. The complexity hits when you have 15 office buildings, 40 construction projects, or joint venture arrangements where emissions need to be allocated by equity share.

Construction companies in particular need per-project emissions tracking, not just per-entity. A Tier 1 contractor might run 200 active projects simultaneously, each with its own fuel consumption, waste streams, and material inputs. The platform needs to track emissions at the project level, roll them up to the entity level for NGER, and handle the fact that some projects are 100% owned while others are 50/50 joint ventures requiring equity-based allocation.

Most carbon accounting platforms were designed for corporate-level reporting. Per-project tracking and JV allocation are afterthoughts, if they exist at all. During evaluation, ask: "How do you handle equity-based emissions allocation for joint ventures? Can I track emissions per project and consolidate to corporate level?" If the answer involves a workaround with spreadsheets, that tells you something.

We built Carbonly's JV collaboration module specifically for this. Multi-organisation consolidation with equity-based allocation, so each party sees their proportional share without duplicating data entry. We're not aware of another Australian carbon platform that handles JV allocation natively. It was one of the first features our team designed, because it's exactly the problem we kept hitting in mining and construction over 18 years of enterprise data work.

What happens when emission factors change?

The NGA Factors workbook is updated annually by DCCEEW. State-based grid emission factors shift as the energy mix changes (more renewables coming online, coal plants retiring). When the 2025 edition dropped, it included updated scope 2 and 3 electricity factors and, for the first time, scope 1 factors for hydrogen combustion.

In a spreadsheet world, someone has to notice the update was published, download the new workbook, manually update every factor in the calculation file, and hope they didn't miss one. We've seen organisations submit NGER reports using factors from two years prior because nobody updated the reference table.

Your software should maintain its own emission factor database, update it when new editions are published, and flag which reporting periods used which factor versions. That way, if an auditor asks why your 2025-26 Scope 2 figures differ from 2024-25, you can show it was because DCCEEW updated Victoria's grid factor, not because someone changed a formula.

Ask: "When was your emission factor database last updated? Do you track which factor version was used for each calculation?" This sounds like a minor detail. It isn't. The Clean Energy Regulator can and does issue compliance actions for incorrect factor application.

Pricing models that penalise growth

Software pricing in this market typically follows one of three models: per-seat (you pay for each user), per-entity or per-site, or per-project.

Per-seat pricing works for companies with large sustainability teams. But most mid-market companies have one or two sustainability staff managing dozens of sites. A 200-project construction contractor with three sustainability analysts doesn't need 200 logins. They need three people to manage 200 projects. Per-seat pricing is fine for them. Per-project pricing penalises them for growing their business.

Some platforms charge by revenue band, which at least aligns cost with company size. Others bundle everything into annual contracts with implementation fees that can run $50,000 to $150,000 for enterprise platforms before you've calculated a single emission.

Carbonly uses per-project pricing, which means the cost scales with how much you actually use the platform, not how many people need access. A growing construction company adding projects shouldn't face a step-change in software costs every time they win a tender. Contact hello@carbonly.ai for specific pricing, but the model is designed so that a 200-project contractor and a 20-project contractor both get access to the same full platform, just at different scales.

We'd encourage you to get pricing details from every vendor you evaluate. Ask for the total annual cost including implementation, training, and ongoing support. Don't just compare licence fees. A platform that costs $15,000 per year but requires $40,000 in implementation consulting isn't cheaper than one that costs $25,000 with onboarding included.

The one thing we'd check that nobody talks about

Consultants are a major part of this market, and good ones are worth every dollar. Many sustainability consultants use carbon accounting software to scale their practice, serving more clients without proportionally growing headcount. So when evaluating platforms, ask whether consultants can work within the system alongside your internal team.

A platform that locks out your consultant, or makes it difficult to share project-level access, creates friction you don't need during reporting season. And a consultant who can see the raw data, the extraction results, and the audit trail inside the platform can add more value than one who's rebuilding everything in their own spreadsheet.

We don't know every buyer's situation. Some companies will be better served by a consultant-led engagement with software as the backbone. Others will run it internally from day one. The point is, the platform shouldn't force that choice. It should support both.

Before you sign anything

Run a real trial with your actual documents. Not their demo data. Not a curated sample set. Your messiest electricity bill, your worst scanned fuel docket, a supplier invoice that even your own team struggles to read.

Then check these things:

Did the platform extract consumption data without manual entry?
Were the correct NGA emission factors applied automatically?
Can you trace the reported figure back to the source document in under a minute?
Does the output structure align with NGER and AASB S2 requirements?
Can you see exactly which factor edition and GWP values were used?
Does multi-site or multi-project tracking work without spreadsheet workarounds?

If the answer to any of those is no, keep looking. Because the regulatory environment isn't getting simpler. ASRS Group 2 reporting starts for financial years beginning 1 July 2026. ASSA 5010 requires limited assurance from Year 1. The ACCC doubled maximum greenwashing penalties to $100 million per contravention in March 2026. Your numbers need to be right, traceable, and defensible.

We built Carbonly to meet every criterion on this list. But don't take our word for it. Run the trial. Upload your documents. See what comes back. That's the only evaluation that matters.

Reach out at hello@carbonly.ai if you want to test it with your own data.

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