Your company reports Scope 2 under the GHG Protocol and covers part of its electricity with annual guarantees of origin. Your verifier checks the inventory against ISO 14064-1. Both sets of rules are changing. The GHG Protocol and ISO will publish one joint corporate standard. The new Scope 2 rules may also stop counting annual certificates from distant markets.
- Scope 2 guidance revision: the GHG Protocol proposed that certificates match energy use by the hour and come from the same grid.
- Joint standard: the GHG Protocol and ISO plan public consultation in mid-2027 and publication at the end of 2028.
- Current reports: stay valid and need no correction; the start date of the new rules is not known yet.
- Product footprints: a joint GHG Protocol and ISO standard for product carbon footprints is the first priority.
- Action now: check where your guarantees of origin come from and start collecting hourly data on energy use.
Two systems for one carbon footprint
For years, companies that calculate their emissions have worked with two parallel systems. They are consistent with each other, but separate:
GHG Protocol: developed by WRI and WBCSD and used by 97% of S&P 500 companies that report to CDP. It defines Scopes 1, 2 and 3 and gives guidance for companies and value chains.
ISO 14060 family: in particular ISO 14064-1 (organisations), ISO 14064-2 (reduction projects) and ISO 14067 (product carbon footprint). ISO standards put more weight on formal verification and are widely used in Europe.
The two systems agree on the basics but differ in details. These include terms, scopes, boundaries and how reports are checked. This caused practical problems:
- Companies in global markets had to check that they met both sets of requirements.
- Auditors and verifiers worked with different frameworks, so data was harder to compare.
- Supply chains had trouble sharing product carbon footprint (PCF) data between suppliers that used different standards.
- CSRD and ESRS required the GHG Protocol but also allowed ISO 14064-1, under conditions.
What is the ISO and GHG Protocol partnership?
On 9 September 2025, ISO and the GHG Protocol signed a strategic partnership. Its aim is clear: to merge both systems into one set of standards with both brands. It will become one global language for GHG accounting.
The COP30 Action Agenda named the partnership a key step towards carbon accounting that is reliable and comparable worldwide. The changes cover four areas:
- Shared terms and rules: the same definitions, ways to measure and rules to present data. Companies, auditors and regulators will use one set of rules in every country and sector.
- One standard instead of two documents: one text with both the ISO and the GHG Protocol logos. This applies at company, product and project level.
- A closer link to verification: the accounting rules will fit better with checks under ISO 14064-3 and ISO 14065/17029. This should lower audit costs and make reports more credible.
- Data that works across supply chains: a joint PCF standard should make it easier for suppliers and customers to share detailed, verified product footprint data. This matters, for example, for companies that report Scope 3, category 1 (purchased goods and services).
Three levels of cooperation
The partnership covers three levels of GHG accounting:
| Level | GHG Protocol | ISO |
|---|---|---|
| Corporate | Corporate Standard, Scope 2 Guidance, Scope 3 Standard | ISO 14064-1 |
| Project | GHG Protocol for Project Accounting | ISO 14064-2 |
| Product (PCF) | Product Life Cycle Accounting and Reporting Standard | ISO 14067 |
The new joint PCF standard is the top priority. On 27 October 2025, the partners opened a call for experts to join the Joint Working Group. On 9 February 2026, the GHG Protocol published the list of nominated members. The first call drew 459 experts from around the world.
When will the new standards appear?
Corporate standards: the carbon footprint of an organisation
On 29 July 2026, the GHG Protocol and ISO announced that they will merge the corporate rules into one joint standard. It will combine the Corporate Standard, the Scope 2 Guidance, the Scope 3 Standard and ISO 14064-1. The consolidated draft goes to public consultation in the second quarter of 2027. Publication is planned for the fourth quarter of 2028. The start date has not been announced yet.
The joint PCF standard: the carbon footprint of a product
The detailed timeline for the Product Carbon Footprint Standard:
| Stage | Expected date |
|---|---|
| Launch of the Joint Working Group | Q4 2025 – Q1 2026 ✓ |
| First draft | Q4 2025 – Q3 2026 |
| Internal consultation (ISB and the ISO committee) | Q3 – Q4 2026 |
| Public consultation | Q4 2026 – Q1 2027 |
| Joint approval for publication | Q2 – Q3 2027 |
| Publication of the final standard | Q4 2027 – Q1 2028 |
Scope 2 guidance revision: what is changing?
At the same time, the GHG Protocol is revising its Scope 2 guidance for the first time since 2015. This is a separate but linked process. For many companies it matters more in the short term. It can change how they report emissions from the electricity they buy.
Why does Scope 2 need to change?
The current Scope 2 Guidance (2015) was written for a different world. Renewable energy markets were smaller. Energy attribute certificates (EACs), such as guarantees of origin (GOs) and RECs, were only starting to spread. Tracking energy flows in real time was technically out of reach. Ten years later, the same rules apply to a very different market.
The key problem: annual certificates from distant markets. Today a company can buy a guarantee of origin from a solar plant in Spain. It can then match it with its night-time energy use in Germany and report zero Scope 2 emissions under the market-based method. This meets the current guidance. But it has little to do with the real emissions of the grid.
The main proposed changes
The first public consultation covered five main changes:
- Hourly matching: certificates would have to match energy use hour by hour, not only over a year. A certificate from a given hour would cover only the energy used in that hour. This would end the annual "offsetting" of night-time use with daytime solar output. The proposal does not require hourly matching from all companies at once. Companies without the right meters would get easier options.
- Deliverability: certificates would have to come from generators connected to the same grid as your site. Certificates from markets far from the place of use would no longer count. The aim is that the market-based method reflects the electricity really available on the grid at a given place and time.
- A new order of emission factors: the location-based method would prefer more precise data. An example is hourly grid factors instead of annual national averages. This applies only where such data is available free of charge.
- Scope 2 as a standard, not guidance: the document would become a full standard. This means stricter requirements and a closer link to verification.
- Dual reporting stays: companies still report both the location-based and the market-based result.
In July 2026, the GHG Protocol summarised the feedback. It found strong interest in transparency and in claims that match the reported results. But stakeholders see the climate impact of buying electricity in different ways. So the GHG Protocol will explore whether several reporting approaches can reflect these views. The final shape of the Scope 2 rules is still open.
Debate and industry views
The public consultation (October 2025 – January 2026) caused a heated debate. The main concerns were:
- Cost for smaller companies: EY, KPMG and many business groups said that most companies cannot meet hourly matching today, for technical and financial reasons. This is true above all outside the US and Western Europe. Companies might then choose simpler but less accurate methods.
- Risk for the renewable energy market: the Center for Resource Solutions (CRS) warned that strict rules could make companies buy fewer certificates by choice. In the US, such buying drove 60% of new renewable capacity outside legal quotas.
- Annual certificates in question: some companies base market-based Scope 2 on annual GOs or RECs, with no hourly or geographic matching. They may not be able to count them under the new method.
Timeline of the Scope 2 update
| Stage | Date |
|---|---|
| First public consultation | October 2025 – January 2026 ✓ |
| Summary of the consultation (about 1,100 responses from 56 countries) and decision on a joint standard with ISO | July 2026 ✓ |
| Public consultation on the consolidated draft, including Scope 2 | Q2 2027 |
| Publication of the joint GHG Protocol and ISO corporate standard | Q4 2028 |
What does this mean for reporting companies?
Do current reports need correcting now?
No. Reports made under the current GHG Protocol or ISO 14064-1 stay fully valid. The joint GHG Protocol and ISO standard is due in the fourth quarter of 2028. The start date and any transition period have not been announced yet.
What should you do now?
If you use the GHG Protocol: your method is the basis of the new joint standards. Review your approach to market-based Scope 2 first. Check whether the GOs or RECs behind your market-based result meet geographic criteria. Also check whether your metering can support hourly matching in the future, or at least plan how to get there. The second Scope 2 consultation, announced earlier for 2026, has been replaced. The draft that covers Scope 2 goes to the consolidated consultation in the second quarter of 2027.
If you use ISO 14064-1: your documentation fits the new direction. But remember that ESRS E1 uses the GHG Protocol as its basis. ISO 14064-1 can support it, but cannot replace it.
If you calculate product carbon footprints (PCF): focus on the new joint PCF standard. Companies in supply chains that already collect PCF data from their suppliers will gain directly from one shared method.
For everyone: document your method and data quality well now. The future PCF standard will probably ask for more verification and more data sharing in the supply chain.
Scope 2: audit your energy certificates
Step 1: list the GOs or RECs behind your market-based Scope 2. For each certificate, check:
- Does it come from the same grid that supplies your site? (deliverability)
- Does it match a whole year, or shorter periods?
- Will its registry be accepted under the new method?
Step 2: check how the new method could change your result. You may use annual certificates bought on the national or EU market with no hourly check. Then your current market-based Scope 2 may need recalculating under the new rules. This does not mean your past reports were wrong. But it can affect how your past data compares with future data. You can run your own simulations with statistical data. They show how much hourly coverage your current guarantees give.
Step 3: talk to your energy and certificate suppliers. Ask your PPA or GO supplier whether you can move to certificates matched by hour, or at least by month. In Europe, some registries and platforms already test certificates with hourly time stamps, for example under the EnergyTag standard. This market is still developing.
Step 4: keep reporting the location-based method. Dual reporting remains mandatory. If you do not calculate both methods yet, start now. The location-based method does not depend on certificates. It gives you a stable baseline, whatever happens to the market-based method.
Sources
- ISO press release, 9 September 2025: ISO and GHG Protocol announce strategic partnership
- GHG Protocol, September 2025: ISO-GHG Protocol Partnership: Frequently Asked Questions
- GHG Protocol, April 2026: ISO and GHG Protocol finalize Joint Working Group to develop a product-level standard
- GHG Protocol, October 2025: Upcoming Scope 2 Public Consultation: Overview of Revisions
- GHG Protocol, 29 July 2026: GHG Protocol Announces Key Standard Development Updates