What Energy Attribute Certificates Represent
Energy attribute certificates (EACs) are trackable instruments representing the environmental attributes of 1 MWh of renewable electricity generation. They trade independently of the physical power. Their core function is preventing double counting of renewable energy consumption claims and enabling verifiable corporate energy procurement.
The market is structured around three primary systems: I-REC Standard globally, YEK-G in Turkey, and Guarantees of Origin in the European Union. Each has distinct issuance mechanisms, registry infrastructure, and pricing dynamics.
In 2024, global EAC issuance exceeded 1,000 TWh. Corporate renewable energy commitments — particularly the 400+ companies under RE100 — constitute the primary demand driver.
I-REC Standard: Global Scope, Flexible Framework
The I-REC Standard operates across 45+ countries as a global energy attribute certificate framework. Governed by the non-profit I-REC Standard Foundation, it operates through authorized Local Issuers in each participating country.
Global I-REC issuance volume reached approximately 300 TWh in 2024 (Source: I-REC Standard Foundation, 2024 Annual Report). Southeast Asia, Latin America, and Turkey are the most active markets.
Pricing. A wide band of USD 0.50 to USD 3.00 depending on geography and technology. Southeast Asian hydro I-RECs trade at USD 0.50-0.80, while Turkey I-RECs price at approximately USD 0.40-0.50/MWh. The technology premium is pronounced: solar consistently prices above hydro and wind.
Settlement mechanics. The generator submits production data to the Local Issuer. Post-verification, certificates are registered on the I-REC registry. The buyer purchases and transfers certificates to their account, then executes a redemption (cancellation) to create a consumption claim. Certificate validity is typically 3-5 years from generation — but vintage preference directly impacts price.
Scope 2 eligibility. Accepted under the GHG Protocol Scope 2 Guidance for market-based reporting. RE100 technical criteria also recognize I-REC as a qualifying instrument (Source: RE100 Technical Criteria, 2024 update).
YEK-G: Turkey's National Certificate System
Yenilenebilir Enerji Kaynak Garantisi Belgesi (YEK-G) is Turkey's energy attribute certificate, issued and tracked by EPİAŞ (EXIST) under EPDK regulation. Launched in 2021, the system has become a critical component of Turkey's renewable energy market infrastructure.
Eligible sources: Solar, wind, hydroelectric, geothermal, and biomass. Given Turkey's total renewable installed capacity, YEK-G-eligible generation stands at approximately 12-15 TWh (Source: EPDK 2024 Electricity Market Sector Report).
Pricing. YEK-G certificates trade in the TRY 5-60/MWh range. Transaction volumes on the EPİAŞ Organized YEK-G Market increased notably in 2024. Certificates tied to corporate PPAs typically price in a tighter band than spot market trades.
Corporate PPA linkage. Large consumers in Turkey — particularly export-oriented industrials — structure renewable energy PPAs alongside YEK-G certificates. CBAM-driven reporting obligations for Turkish exporters provide additional demand support for YEK-G.
Limitations. YEK-G is not directly integrated with international registries. While accepted for GHG Protocol Scope 2 market-based reporting, some international verifiers may request additional documentation.
Guarantees of Origin: The EU Standard Framework
The EU's Guarantee of Origin system is structured under the 2009/28/EC Renewable Energy Directive and subsequent RED II. The EECS (European Energy Certificate System) registry operated by the Association of Issuing Bodies (AIB) provides the central infrastructure for cross-border transfers.
Approximately 700 TWh of GOs were tracked through the AIB system in 2024 (Source: AIB Statistics, Q4 2024). This volume corresponds to roughly 25% of the EU's total electricity consumption.
Pricing. Clear differentiation by technology. Wind GOs trade at EUR 1.50-3.50, solar GOs at EUR 2.00-4.00. Nordic hydro GOs have historically been the lowest-priced segment (EUR 0.50-1.00), but CSRD-driven demand is pushing these prices higher.
CSRD linkage. The EU Corporate Sustainability Reporting Directive (CSRD) effectively mandates GO usage for market-based Scope 2 emissions reporting. The expansion of reporting obligations from 2025 onward is driving a structural increase in GO demand.
Cross-border transfer. GO transfers between AIB member countries are executed through the EECS Hub. Transfer processing typically takes 1-3 business days. Transfers from non-EU countries are not possible — meaning Turkish renewable generation cannot directly access the EU market via this mechanism.
Comparison Table: I-REC vs YEK-G vs GO
| Criterion | I-REC | YEK-G | Guarantee of Origin (GO) |
|---|---|---|---|
| Jurisdiction | 45+ countries (global) | Turkey | EU/EEA member states |
| Issuing body | Local Issuers (I-REC Foundation approved) | EPİAŞ (EXIST) | National issuing bodies (AIB members) |
| Registry | I-REC Registry | EPİAŞ YEK-G Platform | EECS Hub (AIB) |
| Validity | 3-5 years from generation | Generation year + 1 year | 12 months from generation |
| Price range | USD 0.40-3.00 | TRY 5-60/MWh | EUR 0.50-4.00 |
| Scope 2 eligibility | Yes (GHG Protocol) | Yes (conditional) | Yes (CSRD reference standard) |
| RE100 acceptance | Yes | Yes | Yes |
| Additionality | Not certificate-based; depends on PPA structure | Not certificate-based | Not certificate-based |
| Cross-border transfer | Yes (inter-registry) | No | Yes (between AIB member states) |
Price Drivers
Technology premium. Solar certificates carry a premium over wind and hydro across all systems. The primary factor is corporate buyer preference for solar in CSRD and CDP reporting.
Vintage effect. Current vintage certificates price 20-40% above older vintages. RE100 technical criteria prefer same-year or prior-year vintage relative to the reporting period.
Additionality demand. EACs do not inherently prove additionality, but certificates from newer facilities (particularly post-2020 commissioning) carry a premium. This demand comes primarily from companies with SBTi (Science Based Targets initiative) commitments.
CSRD and Scope 2 reporting obligations. The expansion of CSRD reporting scope in 2026-2027 is the most visible structural driver for EU GO demand. The ESRS E1 standard explicitly references EAC usage for market-based Scope 2 reporting.
RE100 commitments. Over 400 companies' 100% renewable energy pledges (Source: RE100 Annual Report 2024) support I-REC demand, particularly in emerging markets. RE100 technical criteria define accepted certificate systems and quality conditions.
Turkey corporate reporting. Turkish companies with Scope 2 reporting obligations and RE100 commitments are increasing YEK-G and I-REC procurement to substantiate renewable energy claims. CSRD's expanding extraterritorial scope is adding further demand from Turkish suppliers to EU value chains.
Current Pricing Matrix (Q1 2026)
| Certificate | Technology | Vintage | Price Range | Trend |
|---|---|---|---|---|
| EU GO | Wind | 2025 | EUR 1.80-3.20 | Stable |
| EU GO | Solar | 2025 | EUR 2.50-4.00 | Upward |
| EU GO | Nordic Hydro | 2025 | EUR 0.60-1.20 | Upward |
| I-REC | Turkey | 2025 | USD 0.40-0.50 | Stable |
| I-REC | Wind (India) | 2025 | USD 0.80-1.50 | Stable |
| I-REC | Hydro (Brazil) | 2025 | USD 0.40-0.80 | Stable |
| YEK-G | Wind | 2025 | TRY 5-30/MWh | Stable |
| YEK-G | Solar | 2025 | TRY 20-60/MWh | Upward |
The most notable trend: CBAM's definitive phase (January 2026) has made EAC procurement a compliance necessity for Turkish industrial exporters, structurally supporting YEK-G and I-REC demand.
Trading and Settlement Mechanics
OTC-dominated market. Unlike compliance allowances (EUAs), EAC trading is predominantly OTC. There is no centralized exchange for I-RECs or YEK-G certificates. Transactions are bilaterally negotiated between buyers and sellers, with brokers facilitating price discovery. This OTC structure means bid-offer spreads are wider than for exchange-traded instruments — typically 5-15% of the certificate price.
Settlement cycle. I-REC transfers through the registry typically settle in 3-5 business days. YEK-G transfers on the EPİAŞ platform are faster — 1-2 business days for domestic transfers. EU GO transfers through the EECS Hub take 1-3 business days between AIB member countries.
Cancellation for reporting. To claim the environmental attribute for Scope 2 reporting, the certificate must be cancelled (retired) in the registry. Holding a certificate in your account is not sufficient — cancellation creates the audit trail that assurance providers require.
Forward purchasing. Corporate buyers with multi-year RE100 or SBTi commitments increasingly sign forward EAC purchase agreements (1-3 year terms). Forward contracts lock in prices and guarantee supply — particularly relevant for solar certificates where CBAM-driven demand growth could tighten availability.
Strategic Considerations for Institutional Buyers
Instrument selection depends on the buyer's geographic footprint, reporting obligations, and procurement strategy:
For EU-based operations: GOs are effectively mandatory for market-based Scope 2 under CSRD. Solar and wind GOs from the country of operation provide the strongest reporting position. Cross-border GOs (e.g., Nordic hydro for a German factory) are accepted but may attract auditor scrutiny under "same market" criteria.
For Turkey operations: YEK-G is the primary instrument, with I-REC as a complement for generation not registered on the YEK-G platform. For companies with Scope 2 reporting obligations, combining YEK-G certificates with facility-level electricity data strengthens market-based emissions reporting under GHG Protocol.
For multinational portfolios: I-REC covers geographies outside GO jurisdiction — India, Southeast Asia, Latin America, Africa. A unified procurement strategy across I-REC and GO systems requires careful vintage and technology alignment.
Price optimization: Technology and vintage selection are the primary cost levers. Cost-sensitive buyers can access lower-cost solutions through hydro certificates and older vintages — but reporting quality assessment must run in parallel. The cheapest certificate is not always the best investment if it creates audit risk or does not meet RE100 technical criteria.