Scope 2 Revision: What Does Hourly Matching Mean for YEK-G Users?

The rules of scope 2 accounting have stayed largely the same since 2015. Companies report the electricity they buy using two methods: the location-based method, which relies on the grid average, and the market-based method, which reflects their purchasing choices. Under the market-based method, consumption matched with a certificate such as a YEK-G (Türkiye's guarantee of origin) or an I-REC can be calculated with the emission factor of renewable energy. This arrangement is on the verge of change, but not as fast as many think. In this post we discuss what has been proposed, the outcome of the consultation, the timeline and what it all means for companies using certificates in Türkiye.

Today's rule: "as close as possible" and "the same market"

The 2015 Scope 2 Guidance requires all contractual instruments used in the market-based method to meet eight quality criteria. The two criteria targeted by the revision are:

• Criterion 4: The instrument must be issued and redeemed as close as possible to the period of energy consumption to which it is applied.
• Criterion 5: The instrument must be sourced from the same market in which the reporter's electricity-consuming operations are located.

In practice, "as close as possible" has allowed annual matching: certificates equal to the MWh consumed over the year can be redeemed regardless of the hour of generation. "The same market" has usually been interpreted as the national border or the scope of the certificate system. For how the location-based and market-based methods are applied today, see our post on correct Scope 2 reporting.

What was proposed?

In the formal process it launched in 2022, the GHG Protocol opened the proposals of its Scope 2 Technical Working Group, made up of around 45 experts, to public consultation in July 2025 with the approval of the Independent Standards Board. The consultation ran from 20 October 2025 to 31 January 2026. The core of the proposals:

• Hourly matching (Criterion 4): For large organizations, certificates would be issued and redeemed for the same hour as consumption. Organizations below a threshold would be exempt and could continue with monthly or annual matching. The options for the threshold were annual consumption (GWh) within a market boundary, a classification based on company size, or a combination of the two; the threshold value was left blank in the consultation document.
• Deliverability (Criterion 5): Certificates would have to come from generation that can reasonably be delivered to the point of consumption through electrical interconnection. The document says that in some countries national borders will approximate the deliverable boundary, while where grid operation differs from national borders, defined market boundaries will apply, citing the market operated by ENTSO-E as an example. Türkiye is not mentioned by name in the document.
• Feasibility measures: Standard load profiles for those without hourly meter data, exemption thresholds, phased implementation and a legacy provision for existing contracts.
• Other updates: Allocating electricity supplied under regulated tariffs (Standard Supply Service) to customers in proportion to their share, updating the definition of the residual mix, and falling back to a fossil-based factor instead of the grid average where no residual mix exists.
• Location-based method: A requirement to use the most precise accessible emission factor (free, publicly available and from a reliable source) and a hierarchy of factors by location and time.

What did the consultation say?

According to the GHG Protocol's summary of 29 July 2026, the consultation received around 1,100 responses from 56 countries; 62 percent of responses came from companies, industry associations and consultants. The main findings:

• The hourly matching and deliverability proposals received low support. On hourly matching, low support was most widespread among companies and industry associations; reporting programmes and data providers were more supportive.
• Participants split around two different "theories of change": one group believed strict rules would suppress voluntary renewable purchasing, while the other argued that hourly and geographic matching is essential for adding new clean capacity to the grid.
• Measures that would exempt most organizations from hourly matching, and a legacy provision for existing long-term contracts, received broad support.
• The residual mix, regulated tariff allocation and fossil-based fallback factor proposals received moderate support.

The next step is also clear: in April 2026 the Independent Standards Board decided first to review the feedback and set a direction; in July 2026 it asked for further work on multiple market-based reporting approaches reflecting the different theories of change and assigned this to the Technical Working Group. In other words, a single, strict hourly rule going straight into the standard is not on the agenda as things stand; but temporal and geographic matching remains at the centre of the debate.

Timeline: a combined revision running to 2028

The first announcements in 2025 expected the revised Scope 2 Standard to be published at the end of 2027. In July 2026 the plan changed: the GHG Protocol is merging the Corporate Standard, the Scope 2 Guidance and the Scope 3 Standard into a single standard (Corporate Standard Version 3.0) to be developed jointly with ISO. The estimated timeline in the Standard Development Plan: the combined draft opens for public consultation in the second quarter of 2027 and is published in the last quarter of 2028. Effective dates are not yet known; the GHG Protocol had previously stated that the new rules would be phased in after publication.

In short, the rule that applies to 2026 and 2027 inventories is the 2015 Scope 2 Guidance. Communications presenting hourly matching as "now mandatory" are wrong.

The one actually moving fast: the SBTi

While the GHG Protocol deliberates, the SBTi has acted. The Net-Zero Standard V2.0, published in June 2026 and effective from 1 February 2027:

• Requires Category A companies to calculate and report, for every activity pool with annual consumption of 10 GWh or more, what percentage of scope 2 electricity is matched hourly with low-carbon electricity. This is a transparency requirement, not a target.
• Requires market instruments used in target implementation to come from plants commissioned or repowered within the 15 years preceding the consumption period, and to be matched to consumption within 12 months.
• Requires activity pool boundaries to be defined by deliverability zones, and grants a legacy provision for existing long-term contracts.

The SBTi also notes that it will carry out a targeted review of its own rules once the GHG Protocol's deliverability zone definitions are clarified. For details, see the SBTi Net-Zero Standard V2 guide.

What it means for Turkish companies using YEK-G and I-REC

Two certificate systems are used in Türkiye. YEK-G, launched by EPİAŞ (Türkiye's energy exchange operator) on 1 June 2021, certifies every 1 MWh of renewable energy fed into the grid by the licensed generation facilities registered in the system, and was developed within the framework of the EU guarantee of origin system and the AIB's European certificate rules. On the I-REC side, according to a 2021 interview published by the I-REC Standard, Türkiye gained a local issuer in July 2020.

Since there is no finalized rule, the following is not a "compliance" checklist but risk management advice:

1. Prioritize domestic certificates. Whatever form deliverability takes, matching consumption in Türkiye with certificates backed by renewable energy generated in Türkiye is the lowest-risk option. Claims based on certificates sourced from abroad will be the most heavily questioned.
2. Inventory your hourly meter data. Map out now which sites give you access to hourly consumption data. Whatever form the proposal finally takes, hourly data is the first requirement both for SBTi reporting and for any new rules.
3. Check the 10 GWh threshold. If you are SBTi Category A, identify the activity pools in which you exceed 10 GWh a year; hourly matching percentage reporting applies there.
4. Ask about the timing and plant behind your certificates. Ask your supplier or the system operator which plant, which commissioning year and which time resolution the certificates you buy come from. The SBTi's 15-year plant age rule applies from today.
5. Set up document management for long-term contracts. The legacy provisions, both those debated by the GHG Protocol and the one accepted by the SBTi, will require you to prove the date and scope of existing contracts.
6. Don't neglect physical reductions. Location-based scope 2 is not affected by certificates, and SBTi V2.0 sets target ambition against the location-based physical inventory. Efficiency and self-consumption (rooftop solar) projects keep their value whatever the rule turns out to be.

For how to use certificates under today's rules, see our post on how to use renewable energy certificates; for where scope 2 sits in the inventory, see the scope 1, 2 and 3 guide.

Conclusion

On scope 2, the direction is clear but the pace is not. Hourly matching and deliverability are being debated as proposals at the GHG Protocol and have moved onto a timeline running to 2028 with the combined standard. The SBTi, meanwhile, has already introduced hourly reporting and the plant age rule. The smart course for Turkish companies is to keep reporting correctly under today's 2015 rules while preparing their data infrastructure and certificate portfolio for potentially stricter rules. In our inventory work at Alalëa, we build scope 2 with both methods and keep certificate and contract documentation verification-ready; for details, see our carbon footprint service.