On 23 October, a typhoon day in Taiwan, a former student of mine reminded me to log on to the International Renewable Energy Market and Tracking System Forum hosted by the Taiwan Institute of Economic Research (TIER). The forum ran online from 2:00 to 4:15 pm, with speakers from Japan, Korea, Germany, the UK and Taiwan on how companies buy renewable electricity and track it with certificates.

The sessions I heard were: Kansai Electric Power on corporate renewable energy procurement across Asia; the Korea Sustainability Investing Forum (KoSIF) on corporate procurement in Korea; Germany's GO register (HKNR) on how the German Guarantee of Origin register works; Granular Energy on how electricity suppliers run hourly matching tariffs; and RECCESSARY on whether green power in Southeast Asia can actually be delivered.

1. Main points

1.1 There is no single way to buy green power

Power market structures, certificate rules and prices vary a lot between countries. In some markets companies can sign power purchase agreements (PPAs); in others they can only buy certificates or a utility green tariff. Taken together, the speakers' experience suggests that a company is unlikely to cover all of its sites through one channel.

Rooftop solar, battery storage and offshore wind combined
Rooftop solar, battery storage and offshore wind combined (AI-generated illustration)

My takeaway is that companies should treat green power procurement as a portfolio and review it every one to two years as national rules change. The rules move quickly, and the international standards below are all still being revised.

1.2 From annual totals to hourly and local

Companies have mostly matched a year of electricity use against a year of certificates. The main international standards and initiatives are now moving toward finer time and location granularity:

Matching power use and generation hour by hour
Matching power use and generation hour by hour (AI-generated illustration)
  • GHG Protocol Scope 2: The 2025–2026 public consultation draft proposed that the market-based method only count certificates matched to hourly consumption and sourced from deliverable grid regions. According to the GHG Protocol, its Independent Standards Board (ISB) showed majority support in July 2026 for developing two market-based methods: Method 1 with hourly matching, deliverability and incrementality requirements, and Method 2 keeping the 2015 approach. None of this is final yet. The next consolidated public consultation is planned for Q2 2027, and the joint GHG Protocol–ISO standard is expected in Q4 2028.
  • SBTi: Version 2.0 of the Corporate Net-Zero Standard requires Category A companies to calculate and report the share of electricity matched hourly with low-carbon electricity in activity pools using 10 GWh or more a year. Companies that reach the thresholds (50% until 2030, 75% until 2035, 90% after that) can be recognised on the SBTi Dashboard. The same version generally requires market instruments to come from projects no more than 15 years old.
  • RE100: The technical criteria require renewable attributes to come from the same market boundary as the consumption, with a 15-year commissioning rule. Hourly matching is not an RE100 requirement, though RE100 collects and recognises time-matching approaches.
  • 24/7 Carbon-Free Energy (24/7 CFE): The 24/7 Carbon-Free Energy Compact promoted by UN Energy aims for every hour of electricity use to be supplied by carbon-free power.

The speakers gave examples such as Korea's new REGO and the hourly products already offered by suppliers in Germany and elsewhere in Europe.

1.3 Certificates as a common language across markets

Most Asian markets use I-RECs, Europe uses Guarantees of Origin (GOs), and Korea is setting up REGO. These certificates let very different power markets be tracked and compared, and they fill gaps where physical supply falls short: when a company cannot buy physical green power at a site, it can still use certificates.

European GOs covering electricity, gas and hydrogen
European GOs covering electricity, gas and hydrogen (AI-generated illustration)

After the forum I checked the Korean Ministry of Climate, Energy and Environment's press release on REGO. Its official name is the certificate for self-consumption renewable energy generation facilities. It covers solar and similar systems in homes and industrial parks that generate power for their own use. Certificates are issued after generation records are confirmed through the Renewable Energy Monitoring System (REMS), one per MWh, and can be sold to companies taking part in RE100. A pilot runs from August to November 2026, and full rollout is planned for 2027.

In the EU, the Renewable Energy Directive (RED II) requires member states to run GO systems and to extend them from electricity to renewable gases, hydrogen, and heating and cooling.

1.4 Supply chain pressure shapes policy and markets

The Korean speaker said that within about five years, Korea quickly built mechanisms for corporate green power procurement because multinational customers such as Apple and BMW asked their suppliers for renewable electricity. In Germany, RED II drove the expansion of the register system. According to the German Environment Agency (UBA), Germany has legislated GO registers for gas (including hydrogen) and for heating and cooling under the Guarantees of Origin Register Act (HkNRG), and these registers are still being built.

2. Observations across sessions

2.1 Certificates and hourly matching point the same way

Seen together, the sessions were consistent: Kansai Electric Power stressed the flexibility certificates provide, the Korean speaker mentioned time stamps on REGO, and Granular Energy showed suppliers in the UK and Europe already running hourly matching tariffs. Certificates are shifting from proof of a year's green power use to records tied to a specific hour and place.

2.2 The gap in Southeast Asia

The RECCESSARY session was titled "Southeast Asia's Green Power: The Door Is Open. Can the Power Get Through?" According to the speaker, annual certificates are easy to get in Southeast Asia, but physical delivery is limited by the grid, permitting and regulation. AI data centres are growing quickly in the region and use power around the clock. If international standards move to hourly matching, storage and hourly verification will need to keep up. This links back to the hourly matching discussed in the Granular Energy session.

Southeast Asian green power needs the grid to reach data centres
Southeast Asian green power needs the grid to reach data centres (AI-generated illustration)

2.3 Taiwan's situation

The speakers noted that green power in Taiwan is expensive and supply is limited. My inference is that Taiwanese companies may need a mixed strategy of domestic procurement plus certificates, while watching what international standards require on certificate eligibility and hourly matching.

Solar-over-fishpond farms and offshore wind on Taiwan's west coast
Solar-over-fishpond farms and offshore wind on Taiwan's west coast (AI-generated illustration)

Taiwan has some groundwork on data. EnergyTag notes that Taiwan has installed more than 3 million smart meters and that certificates from the Taiwan Renewable Energy Certificate Center (T-REC) under the Bureau of Standards, Metrology and Inspection rely on 15-minute meter data, which makes hourly certificates technically possible.

2.4 Korea's path is worth studying

Korea worked backward from customer and supply chain requirements to design its policies and mechanisms. Taiwan's export industries face very similar customer demands, so this path is worth a close look.

2.5 Germany's principles are worth studying

The German speaker stressed avoiding double counting. I checked Section 80 of Germany's Renewable Energy Sources Act (EEG): operators who receive EEG support payments may not pass on GOs for that electricity, with an exception for regional certificates (Regionalnachweise). The speaker also said GOs can only be cancelled for customers with a supply contract. These rules keep certificates credible and stop the same unit of electricity from being sold twice.

The most practical reminder I took from the forum: the rules for buying green power are still changing, so companies should start organising their hourly consumption data now and learn how certificate rules differ from market to market.

References