FAQ

There are three fundamental issues with today’s Scope 2 accounting:
 

• Space (Delivery not required). Today, consumers can claim to be zero-carbon by buying EACs completely untethered from their own real consumption. One can be 100% renewable in New York based on RECs from Texas (which exports little electricity) or 100% Norwegian hydro-powered in Spain, despite little interconnection between these countries.
• Time (Delivery not on time). Today, a consumer can be “solar power all night long” or “wind-powered” based on wind-generated power six months prior. This is not accurate or transparent and stifles critical signals for flexibility and storage.
• Existing CFE Reliance (Delivery of what’s not yours). Today, a consumer can have zero emissions just by buying EACs from an asset they had no role in financing or refurbishing (e.g., 100% old hydro-powered). This is not a fair zero-emissions reflection.

Today, consumers can claim to consume clean power produced at any time of year and often from across a continent through the purchase of Energy Attribute Certificates. This is not representative of grid realities.

Granular accounting enabled by time-stamped Granular Certificates – ensures consumption is matched with clean energy in the same hour from a location where electricity can be delivered and encourages new clean energy supply – addresses the critical issues with today’s accounting. This will make carbon accounting and clean energy claims more transparent and more impactful.

Robust empirical research from the world’s leading experts (see next question) shows various critical benefits that Granular accounting brings:
 

1. Enables consumers to drive deep decarbonization of the grid – every hour.
2. Enables the production of clean products, like hydrogen, without any fossil reliance.
3. Provides more transparency by linking production to consumption in ‘real-time’.
4. Incentivizes storage and flexibility by providing a new price signal.
5. Enables more accurate & transparent carbon accounting.
6. Facilitates better risk management by avoiding volatile fossil-based electricity pricing.

There is growing scientific consensus of the benefits of Granular Certificates purchased following Granular Accounting principles:

1. Princeton University modelling on the effectiveness of electricity procurement strategies in the US shows that temporal matching “drives significant reductions in system-level CO2 emissions” while alternatives like annual matching and emissions matching “have zero or near-zero long-run impact on system-level CO2 emissions.”
2. The IEA show that in the India and Indonesia “shows that hourly matching strategies (as compared to annual) lead to a more diverse technology portfolio, including clean dispatchable generation and storage” the analysis also shows hourly matching is more accurate in terms of emissions and system cost allocation.
3. TU Berlin EU research shows that 24/7 matching “leads to lower emissions for both the buyer and the system.”
4. Princeton University research also shows that hourly matching with new clean supply for US Clean Hydrogen is needed to avoid “significant excess emissions” that appear if alternatives like annual matching and emissions matching are used for clean hydrogen accounting.
5. Modelling from MIT shows that, in cases where large volumes of hydrogen are at play, granular hourly matching is critical to avoiding the production of hydrogen with emissions intensity many multiples that of grey hydrogen.
6. Research of Princeton University demonstrates the benefits of 24/7 PPAs and GC trading.
7. The research of TU Berlin shows the need for 24/7 for EU Green Hydrogen to ensure zero-emissions and avoid significant power price increases.
8. The Florence School of Regulation Study shows significant benefits of 24/7 accounting for Green Hydrogen at little extra cost.
9. The research of the University of California Davis shows hourly accounting increases accuracy over annual accounting by up to 35%.

Granular Accounting and 24/7 CFE has support from a very broad set of global stakeholders including governments, international agencies, NGOs, corporates, and power system operators.

1. 1. The United Nations has a 24/7 carbon free energy compact to build demand for next generation procurement.
   2. It is a US Federal Government goal to procure at least 50% of the electricity required for its operations from carbon-free sources on a 24/7 basis by 2030.
   3. The EU Commission has proposed robust Granular Accounting requirements matching for green hydrogen.
   4. The EU most recent renewable energy law, published in 2023, encourages the rollout of Granular Guarantees of Origin in Europe and removes previous legal roadblocks to their implementation.
   5. C40 Cities, are launching a 24/7 Carbon-Free Energy for Cities program to empower cities around the world to run entirely on clean energy, every hour of every day with an initial focus on Paris, London, and Copenhagen.
   6. Leading corporates like Google and Microsoft and Iron Mountain have set targets to source clean power on a 24/7 basis.
   7. The EU’s transmission system operators have unanimously called for Granular Accounting which will lead to renewables being developed “in the right time and in the right geographical location.”
   8. Dozens of the world’s leading climate NGOs have signed onto letters supporting Granular Accounting for green hydrogen.

Energy Attribute Certificates (EAC) markets have existed for more than two decades. These are now well-established, mature markets, which have stood the test of time and played a key role in enabling consumer energy choice. Granular Certificates and accounting are a natural evolution of today’s EACs and annual matching and are a yardstick for ensuring deep grid decarbonization and more transparency and impact in clean energy markets.

Granular accounting is a refinement of today’s Scope 2 accounting rather than being a fundamental change of method.

Yes,  global certificate systems are rapidly shifting toward hourly standards, driven by major policy frameworks like the EU’s Renewable Energy Directive III (RED III), which mandates Granular Guarantees of Origin; U.S. registries such as M-RETs and PJM, which already issue hourly Energy Attribute Certificates; and Taiwan’s T-REC system, which has operated on 15-minute intervals since 2017. In parallel, the I-REC Standard is enabling hourly Granular Certificates in over 50 countries. This global transition is supported by organizations like EnergyTag, international agencies like the IEA, and leading academic institutions, including Princeton, TU Berlin, and MIT, all of which provide the technical and scientific foundation for hourly carbon-free energy accounting.

Marginal emissions accounting is unreliable for Scope 2 reporting because it estimates avoided emissions based on hypothetical scenarios, lacks verifiability, ignores long-term system impacts, and can lead to misleading claims, similar to carbon offsetting.

EnergyTag is currently developing a robust standard for storage accounting, which meets the challenges associated with avoiding double-counting and ensuring credible storage claims.
 
Among the topics that being addressed in the standard are:
 

1. Treatment of energy losses in various energy storage systems.
2. Allocating granular certificates to stored energy in a climate-credible and storage-operable way.
3. Implementing the storage standard in a granular certificate registry.

The EnergyTag Standard allows for tracking electricity coming from all sources, and EnergyTag remains technology-agnostic. This means that nuclear power can be tracked, and since it generates carbon-free electricity, it can be classified as a clean energy source for the purpose of carbon accounting.

Nevertheless, EnergyTag does not, and never will, force the use of nuclear power to achieve net-zero goals, and the technology choice remains dependent on national/regional regulations and customer preferences. Moreover, projections from the International Energy Agency and other leading institutions show that, while Nuclear will have a role in a net-zero economy, the energy transition will be dominated by renewables.

Only certificate registries or issuing bodies that meet the EnergyTag Standard and have been accredited by EnergyTag can issue Granular Certificates (GCs).

These entities typically include national or regional energy certificate registries, transmission system operators (TSOs), and trusted third-party platforms with the technical ability to issue time-stamped certificates based on verified hourly metering data.

EnergyTag is a non-profit organization that sets a voluntary standard for hourly matching and Granular Certificates. It does not, however, issue or sell Granular Certificates or perform any demonstration tracking projects, nor does it develop dedicated software. Therefore, granular or time-stamped certificates cannot be sourced through EnergyTag directly but rather through our partners listed in the Use Cases section of this website.

Other hourly matching projects active around the world are based on agreements between energy suppliers, consumers, led by software providers etc. You can see a list of some of them on our website.

If you are interested in setting up an hourly tracking demonstration project, or would like to have your hourly matching scheme audited against the EnergyTag Standard, contact us at killian@energytag.org.

Accreditation ensures that Granular Certificates are issued consistently, transparently, and credibly, helping buyers, regulators, and stakeholders trust the environmental claims associated with hourly matching.

By independently verifying compliance with EnergyTag’s Granular Certificate Standard, the accreditation process reduces greenwashing risk, supports credible Scope 2 reporting, and encourages investment in clean, time-aligned energy.

Accreditation is granted based on compliance with the EnergyTag Granular Certificate Standard, which includes key criteria such as:

• Time granularity, typically hourly or sub-hourly.
• Geographic deliverability of energy.
• Data integrity from trusted metering sources.
• Prevention of double-counting.
• Transparent registry governance.
• Support for 24/7 matching and additionality.

The complete list of criteria can be found in the Accreditation documents.

Yes absolutely, and there are many examples of this today. EnergyTag’s Case Studies prove GCs are a technical reality, with over 1 TWh of hourly tracking already performed to date. Some specific examples:

1. Since its inception, the Taiwanese REC system has only ever performed 15-minute tracking. Leapfrogging many systems around the world proving that Granular tracking at a country level is possible.
2. Google are doing hourly tracking with T-EACs (i.e. GCs) across their global operations.
3. M-RETs already offers hourly tracking across the US doing its first hourly REC retirement in 2021.
4. PJM is also providing time-stamped energy certificates since March 2023.
5. FlexiDAO is working with various partners on Granular Certificate schemes.
6. Energy Track and Trace – three European transmission system operators offering an hourly matching product.
7. Nord Pool and Granular Energy are setting up a GC spot market in the UK.

The next key step is full scaling-up of registries to offer hourly tracking to all clients. M-RETs (the US’s largest) predicts this can be done in about 12 -18 months.

TU Berlin and Princeton modelling shows that up to 90-95% 24/7 matching is not much more expensive than 100% annual matching, although it is acknowledged that cost premiums will increase to get to 100%. This is normal, as the technologies needed to achieve 100% matching are still expensive, and will need to be incentivized to drive down costs. Studies have shown that new long-duration energy storage technologies or clean-firm resources like geothermal greatly improve the competitiveness of 100% hourly matched solutions.

If getting to 100% matching was no more expensive than annual matching, everyone would be doing it, but it wouldn’t bring the right benefits for the system. Getting to 100% carbon-free on an hourly basis reflects the actual (higher as of now) cost of decarbonizing the entire electricity supply. Decarbonization is hard, let’s have an accounting system that reflect this.

However, the purpose is to start implementing 24/7 matching as soon as possible, regardless of the percentage matched, rather than matching 100% 24/7 straight away. The cost of the premium for 100% matching will drop over time.

Performing 24/7 matching is meant to provide price signals that are not present today, to incentivize various technologies and drive down their cost curves, as they are not currently competitive.

Crucially, PPAs with a high percentage of hourly matching are also much better for hedging, providing better price visibility than annual PPAs (due to reduced spot market exposure). A fixed price for a significant portion of customer sourcing is very beneficial in reducing energy-related cost volatility, with the related “saving or expense” only being known after the long-term contract has been settled.

The main data required for hourly matching is hourly metering data for production and consumption (sources of this already exist, and are used for energy settlements), and this will be needed also for other use cases as well in the future.

Some national systems have from the outset been set up on a (sub)hourly basis, such as the Taiwanese REC system, without prohibitive costs. As shown in the Case Studies section of our website, several other registries around the world are already developing an hourly tracking infrastructure. Some US registries (M-RETs and PJM) already have hourly tracking available. These systems were developed by small teams (less than 5 people) in 12-18 months, so the required effort is far from prohibitive. In the case of M-RETs, the budget for operating the system is less than USD 1.5 million per year (for comparison, the cost of one offshore wind turbine is about USD 5 million).

The data volumes for Granular Certificates will be larger than for annual certificates but will remain relatively modest. For example, we estimate that to track all of Europe’s electricity with GCs this would be equivalent to the data produced by one autonomous vehicle in a year and require the electricity used by an average school building to store.

Achieving 100% annual renewable supply has set the precedent that getting to 100% should be simple and relatively easy – however, in reality achieving an hourly matching target of 100% is more challenging. Grid decarbonization is hard, and we need an accounting system that acknowledges this and sends the right signals to address the issues. It is acceptable – in fact, it is quite normal – to gradually increase hourly matching until 100% can be achieved.

It is a journey that can and should be started today by anyone, as getting to 100% 24/7 may take a decade or more to achieve. Even companies like Google and Microsoft are unlikely to be there until 2030.

There are many steps you can take to get started, even before setting a target. Signing a 24/7 contract with some hourly matching is a good start.

Google and Microsoft have already signed large 24/7 deals with 80-90% matching.

Yes, several government-led tenders and auctions are already incorporating hourly matching principles. Examples include the U.S. Department of Energy’s 24/7 clean power procurements, India’s round-the-clock tenders, and the Dutch government’s offshore wind auctions, which require bidders to match supply with demand on an hourly basis using firmed portfolios.