Offshore Energy Accounts

After completing this Circular, readers will be able to compile accounts for offshore energy resources within the ocean accounting framework, covering both non-renewable mineral and energy resources (offshore oil and gas, seabed minerals) and the newly recognised renewable energy resources (offshore wind, tidal, and wave energy) following the 2025 SNA adoption of renewable energy resources as a distinct asset category (AN322).

The guidance draws on the general asset accounting methodology in TG-3.1 Asset Accounts and the economic activity classifications in TG-3.3 Economic Activity Relevant to the Ocean, and connects to greenhouse gas accounting in TG-3.4 Flows from Economy to Environment.

Essential prerequisites:

• TG-0.1 General Introduction to Ocean Accounts: conceptual framework and scope of Ocean Accounts
• TG-3.1 Asset Accounts: general asset accounting methodology including standard account structure and valuation

Helpful background:

• TG-0.2 Overview of Relevant Statistical Standards: statistical foundations in SNA 2025, SEEA CF, and SEEA EA
• TG-3.3 Economic Activity Relevant to the Ocean: industry classifications for offshore energy sectors
• TG-3.4 Flows from Economy to Environment: greenhouse gas accounting related to energy production
• TG-2.4 Environmental (including Ecosystem) Goods and Services Section 3.10: valuation method preference order; TG-3.1 Asset Accounts Section 3.3: net present value and resource rent estimation
• TG-6.9 Offshore Energy Thematic Methods: the sector-operational layer built on this Circular’s account structures

The ocean domain contains energy resources central to national energy portfolios and sustainable development strategies. Offshore energy encompasses both extractive activities targeting non-renewable resources beneath the seabed (oil, natural gas, minerals) and the capture of renewable energy from marine environments (wind, tidal, wave). These activities have distinct accounting treatments, whilst sharing common challenges related to spatial delineation, valuation in the absence of market transactions, and management of environmental impacts including decommissioning obligations.

This section is organised to provide both conceptual guidance and practical compilation procedures. Section 3.1 establishes the asset classification framework. Section 3.2 provides a step-by-step compilation procedure for offshore energy accounts. Sections 3.3-3.5 address specific energy types (offshore wind, tidal and wave, oil and gas). Section 3.6 covers decommissioning considerations. Section 3.7 presents a worked example with synthetic data demonstrating the full compilation workflow. Cross-references to related circulars are provided throughout.

Table 1: Offshore energy asset-flow linkages

Note: Produced assets (platforms, turbines) are separate from the energy resources and are recorded in the produced asset accounts (AN.11).

Classifying an offshore energy asset turns on two sequential questions: whether it was produced or constructed and, if not, whether the underlying resource depletes with use. These questions route each asset into a produced asset account (AN11), a non-renewable natural resource account (AN321), or the renewable energy potential account (AN322), the values of which must not be summed because they are recorded in incompatible units (Figure 3.10.1).

1. Non-renewable mineral and energy resources (AN321) — consisting of known deposits of oil, natural gas, coal, peat, non-metallic minerals, and metallic minerals that are economically exploitable given current technology and relative prices

2. Renewable energy resources (AN322) — comprising the cumulative quantities of kinetic, radiative, and thermal energy recoverable from moving water (hydro and ocean energy), moving air (wind energy), hot underground and surface rock and water (geothermal resources), and incident solar radiation (solar resources)

For renewable energy resources, the 2025 SNA recommends the following breakdown:

• AN3221: Wind energy resources
• AN3222: Solar energy resources
• AN3223: Water energy resources (including ocean energy)
• AN3224: Geothermal energy resources
• AN3229: Other renewable energy resources

This classification enables separate tracking of offshore wind (AN3221) and marine-based water energy including tidal and wave (AN3223) within a coherent statistical framework.

3.1.2 Relationship between renewable energy resources and land

A central conceptual issue for offshore energy accounting concerns the relationship between renewable energy resources and land (or seabed). The 2025 SNA notes that “although these resources as such are generally not scarce, the exploitation of these resources may be restricted to certain economic agents, for example by needing permissions to put wind turbines on land, or having ownership of particular pieces of land which are highly favourable for exploiting renewable resources”.

The SEEA CF addresses this issue directly for offshore renewable energy: “It is recognized that some investments in the capture of energy from renewable sources take place offshore (e.g., wind farms in the sea). By convention, the value of income streams from these sources are attributed to the value of land”. Under this convention the value of offshore renewable energy resources is conceptually linked to the value of the seabed or marine areas over which exploitation rights are exercised.

For practical accounting purposes, this guidance implies that:

The treatment of offshore marine areas as “land” for accounting purposes is a convention adopted in the SEEA CF to enable valuation of renewable energy resources in locations where traditional land ownership does not apply. For ocean accounting, this convention should be understood within the broader spatial framework for marine areas established in TG-0.2 Overview of Relevant Statistical Standards. In practice, the economic value attributed to seabed areas reflects the present value of expected income streams from energy exploitation, including the effect of any regulatory restrictions on access. Compilers should record the spatial location of these assets using the Basic Spatial Unit (BSU) approach and document the convention applied.

3.1.3 Distinguishing produced assets from natural resources

Offshore energy accounting requires careful distinction between natural resource assets and the produced assets (fixed capital) used to exploit them. For offshore energy:

• Natural resource assets include the oil and gas deposits themselves, seabed mineral resources, and the renewable energy potential of offshore locations
• Produced assets include drilling platforms, pipelines, wind turbines, tidal turbines, substations, and associated infrastructure

The 2025 SNA emphasises that “the costs of ownership transfer, which are part of fixed capital formation, must be shown separately in the capital account and not as part of the value of the transaction in the non-produced asset”. This separation ensures that investments in extraction/generation infrastructure are properly distinguished from the underlying natural resources.

For aquatic resources, a parallel distinction applies between cultivated and natural resources. However, for mineral and energy resources, all such resources are classified as non-produced natural resources regardless of the intensity of extraction activity.

• Marine area definition — identify the portions of the Exclusive Economic Zone (EEZ), territorial sea, or extended continental shelf where energy resources are located or exploited
• BSU alignment — ensure offshore energy data can be spatially linked to the Basic Spatial Unit framework used for ocean accounts
• Coordination with terrestrial accounts — establish boundaries between offshore and onshore energy accounts to avoid double-counting (particularly relevant for nearshore installations)

Document the spatial conventions applied and any deviations from standard maritime boundaries.

Step 2: Identify data sources

Compile relevant data sources for physical stocks and flows:

For offshore oil and gas:

• Operational installations (existing generating capacity)
• Consented projects (approved for development but not yet built)
• Resource potential (technical potential not yet subject to development consent)

Step 4: Compile physical opening stocks

Record the physical quantity of each asset category at the beginning of the accounting period:

• Oil and gas — volumes in place (barrels of oil equivalent, cubic metres) by field and resource class
• Offshore wind — installed capacity (MW) by location, technology type (fixed-bottom, floating), and water depth
• Tidal and wave — installed capacity (MW) where operational, and theoretical potential (TWh/year) for undeveloped resources

Ensure consistency with closing stocks from the previous accounting period. Where this is the first compilation, document the method used to establish initial stocks and any assumptions required.

Step 5: Record additions to stock

Identify and quantify all increases in resource stocks during the accounting period:

For non-renewable resources:

• Discoveries — new fields identified through exploration
• Upward reappraisals — revisions increasing estimated reserves based on improved geological knowledge
• Reclassifications — transfers from Class B to Class A as economic conditions or project status changes

For renewable resources:

• Decommissioning — removal of installed capacity at end of operational life
• Catastrophic losses — destruction of turbines due to extreme weather or marine accidents
• Downward reassessments — reductions in estimated technical potential due to spatial conflicts (e.g., designation of marine protected areas precluding energy development)

Note that for renewable resources, there is no equivalent to “extraction” as a stock reduction, since the energy source itself is not depleted by use.

Step 7: Calculate physical closing stocks

Apply the asset account identity:

Closing stock = Opening stock + Total additions - Total reductions

Verify that the calculated closing stock is consistent with independent assessments where available. Investigate and reconcile any material discrepancies.

Step 8: Estimate monetary values

Apply valuation methods appropriate to each asset type, following TG-2.4 Environmental (including Ecosystem) Goods and Services Section 3.10 and TG-3.1 Asset Accounts Section 3.3:

For commercially recoverable oil and gas (Class A):

Use the net present value (NPV) approach based on expected resource rents:

NPV = Σ (Resource rent in year t) / (1 + discount rate)^t

Where resource rent = Revenue - Operating costs - User costs of produced capital - Return to produced capital

Key parameters:

Where market transactions in offshore wind lease rights exist, these may provide direct indicators of resource value.

For tidal and wave:

Given limited commercial deployment, monetary valuation may not be feasible. Record physical potential and flag for future valuation as technologies mature.

Step 9: Allocate assets between government and extractors

For non-renewable resources subject to government ownership and licensing arrangements, allocate asset values between:

• Government — reflecting ownership of in situ resources and receipt of resource rents through royalties, production shares, or resource taxes
• Extractors — reflecting their share of resource rents after government take

• Allocate greenhouse gas emissions from oil and gas extraction to marine spatial units (TG-3.4 Flows from Economy to Environment)
• Reconcile with broader economic activity accounts (TG-3.3 Economic Activity Relevant to the Ocean)

3.3.1 Scope and measurement boundary

Offshore wind energy has expanded in recent decades, with installed capacity growing in major maritime economies. For ocean accounting purposes, the measurement scope encompasses:

• Physical resource potential — the theoretical and technical potential for wind energy generation at offshore locations, measured in terms of wind speed, consistency, and site characteristics
• Installed capacity — the maximum power output of installed wind generation equipment (measured in megawatts, MW)
• Actual generation — electricity produced from offshore wind (measured in megawatt-hours, MWh, or equivalent energy units such as terajoules, TJ)
• Infrastructure assets — turbines, foundations, substations, cables, and other produced assets

Table 2 provides an example structure for a physical account of offshore wind capacity. The structure follows the general asset account format established in TG-3.1 Asset Accounts, adapted for renewable energy infrastructure. Compilers may disaggregate further by water depth category (shallow, transitional, deep), distance from shore, or marine planning area as appropriate for national circumstances.

Table 2: Physical account for offshore wind capacity (MW)

3.3.3 Monetary valuation of offshore wind resources

The monetary value of offshore wind resources can be estimated using the net present value (NPV) approach. The resource rent attributable to offshore wind comprises the income remaining after deducting all costs including:

• Operating and maintenance costs
• User costs of produced assets (depreciation of turbines, foundations, cables)
• Return to produced capital
• Any payments to government for exploitation rights

The SEEA CF notes that “opportunities to earn resource rent based on sources like wind, solar and geothermal should be expected to be reflected in the price of land”. For offshore wind, this implies that the value of seabed lease rights or development permits may provide market-based indicators of resource value.

Key considerations for NPV calculations include:

1. Expected generation profile — accounting for capacity factors that vary by location and technology
2. Electricity price assumptions — including long-term power purchase agreements where applicable
3. Operating life — typically 25-30 years for offshore wind installations
4. Discount rate — consistent with rates applied to other natural resources in national accounts

For worked examples applying the NPV approach to offshore energy resources, see Section 3.7 below and TG-6.9 Offshore Energy Thematic Methods.

Offshore wind development occurs within designated lease areas typically located within the exclusive economic zone (EEZ). The spatial framework for ocean accounts should enable linking of offshore wind data to specific marine areas using the Basic Spatial Unit (BSU) approach.

Tidal and wave energy represent emerging renewable energy technologies that capture energy from ocean water movement. Under the 2025 SNA classification, these resources fall within water energy resources (AN3223).

The SEEA Central Framework and FDES define renewable energy from marine sources to include:

• Tidal energy — energy captured from tidal flows and tidal range (barrage systems)
• Wave energy — energy captured from surface waves
• Ocean thermal energy conversion (OTEC) — energy derived from temperature differences between surface and deep ocean waters
• Salinity gradient energy — energy from salinity differences between freshwater and seawater

These technologies are at varying stages of commercial development, with tidal stream and tidal barrage representing the most mature approaches. Wave energy technologies remain largely at demonstration stage in most jurisdictions. Accordingly, guidance for tidal and wave energy follows the same accounting principles as offshore wind, whilst recognising that data availability will be more limited and that compilation methods may need to accommodate fast-changing technologies. As marine renewable energy technologies mature and deployment scales increase, this section may be expanded in future revisions of this Circular to provide more detailed guidance on measurement methods and accounting treatments specific to each technology type.

3.4.2 Physical accounts for tidal and wave energy

• Tidal range and current velocities at potential sites
• Wave height, period, and direction statistics
• Seasonal and inter-annual variability

These assessments provide the physical basis for understanding exploitable resources, analogous to resource classification for mineral deposits. The three-class framework used for mineral resources in SEEA Energy (commercially recoverable, potentially commercially recoverable, non-commercial) could be adapted for emerging marine renewable resources to distinguish sites by development readiness.

3.5 Offshore Oil and Gas

3.5.1 Asset classification framework

Offshore oil and natural gas deposits are classified as non-renewable mineral and energy resources (AN321) within the 2025 SNA framework. The SEEA Central Framework and SEEA Energy provide detailed guidance on asset accounts for these resources, based on the United Nations Framework Classification for Resources (UNFC-2009).

The UNFC categorises mineral and energy resources according to three criteria:

• Economic and social viability (E) — the degree of favourability of conditions for commercial viability
• Field project status and feasibility (F) — the maturity of development plans
• Geologic knowledge (G) — the level of certainty regarding quantities

These criteria define three classes of known deposits:

• Class A: Commercially recoverable resources — deposits where extraction has been confirmed economically viable (E1, F1)
• Class B: Potentially commercially recoverable resources — deposits expected to become economically viable (E2 or E1, F2.1 or F2.2)
• Class C: Non-commercial and other known deposits — deposits not expected to become viable in the foreseeable future (E3)

For monetary valuation and balance sheet purposes, only Class A resources are typically valued, as the timing and magnitude of income from Class B and C resources cannot be determined with confidence.

Compilers should note that the UNFC has been updated since 2009, with the UNFC-2019 incorporating specifications for renewable energy resources and injection projects alongside the original fossil energy and mineral resource categories. The three-class framework (A, B, C) used in the SEEA Energy remains applicable for non-renewable resources. For renewable energy resources, the UNFC-2019 bridging document provides mapping between UNFC categories and the 2025 SNA asset classification, though practical application to offshore renewables is still developing.

3.5.2 Physical asset accounts

Physical asset accounts for offshore oil and gas should record opening and closing stocks and all changes during the accounting period. The standard categories of change include:

Additions to stock:

• Discoveries — new deposits confirmed during the period
• Upward reappraisals — revisions based on improved information
• Reclassifications — transfers between resource classes

Reductions in stock:

• Extraction — quantities removed from deposits
• Catastrophic losses — rare for subsurface resources but may include uncontrolled well events
• Downward reappraisals — revisions reducing estimated quantities
• Reclassifications — transfers between resource classes

Table 3 provides an example structure. The format follows the general asset account structure established in TG-3.1 Asset Accounts. Compilers should disaggregate by field, marine area, or resource class as appropriate, using the BSU spatial framework to enable integration with other ocean accounts.

Table 3: Physical asset account for offshore oil resources (Class A, million barrels)

The monetary value of offshore oil and gas resources is estimated using the NPV approach, based on expected future resource rents. Resource rent represents the surplus income after deducting:

• Operating costs of extraction
• User costs of produced capital (depreciation plus return)
• Costs of mineral exploration and evaluation

Key considerations include:

Price volatility: Oil and gas prices fluctuate, creating volatility in resource rent estimates. The SEEA Energy recommends using smoothed price series or proxies (e.g., moving averages) to derive unit resource rents for projection.

Resource life: The resource life (stock divided by extraction rate) determines the period over which resource rents are discounted. At current extraction rates, this may range from under 10 years to several decades depending on field characteristics.

Depletion: For non-renewable resources, physical depletion equals extraction. In the Ocean Accounts Framework (TG-0.1), this corresponds to Edge E9 (SG3→FG1), where extraction of environmental stocks feeds economic production flows. Monetary depletion is calculated by multiplying physical extraction by the resource price in situ. The 2025 SNA treats depletion as a cost of production alongside depreciation, supporting depletion-adjusted measures of income.

3.5.4 Allocation of income and assets

Offshore oil and gas resources are typically subject to government ownership, with extraction conducted by licensees who pay various forms of rent (royalties, production sharing, resource taxes). The SEEA CF provides guidance on allocating assets and depletion between government and extractors based on their respective shares of resource rent.

The recommended treatment records:

• Total depletion in the production account of the extractor
• Rent payments from extractor to government in the allocation of primary income account
• A balancing entry “depletion borne by government” reflecting the government’s share of depletion

This ensures that depletion-adjusted measures correctly attribute the cost of resource use to both extractors and resource owners. The allocation of assets and depletion between government and extractors varies by jurisdiction depending on the fiscal regime applied to offshore resources (royalties, production sharing agreements, resource rent taxes, or hybrid systems). For detailed treatment of asset allocation methodology, see TG-3.1 Asset Accounts. Compilers should document the national fiscal arrangements and allocation methodology applied in their compilations.

3.5.5 Greenhouse gas implications

Offshore oil and gas extraction generates greenhouse gas emissions through:

• Combustion of fuels for extraction operations
• Flaring and venting of associated gas
• Fugitive emissions from equipment and processes
• Downstream emissions from the use of extracted products

These emissions should be recorded in emissions accounts following the guidance in TG-3.4 Flows from Economy to Environment. In the Ocean Accounts Framework (TG-0.1), these residual flows correspond to Edge E1 (FG1→SG3), recording pollution and emissions from economic production to the marine and atmospheric environment. The spatial attribution of emissions to marine areas enables analysis of ocean-based contributions to national greenhouse gas inventories.

As the energy transition proceeds, offshore oil and gas accounts need to be read alongside renewable energy accounts. Tracking both within a consistent framework supports analysis of energy system transformation and its implications for ocean economies.

3.6.1 Framework for decommissioning costs

Offshore energy installations require decommissioning at end of operating life, with potential environmental remediation obligations. The SEEA CF provides detailed guidance on accounting for these costs, distinguishing between:

• Terminal costs — costs anticipated during production that can be provided for over the asset’s life
• Remedial costs — costs incurred after operations cease, often by parties other than the original operator

Terminal costs should be anticipated and written off over the operating life of the associated fixed asset through consumption of fixed capital (depreciation). This treatment ensures that net income measures properly reflect the full costs of resource extraction, including future restoration obligations.

The 2025 SNA defines terminal costs as “Costs incurred on the disposal of an asset or at the end of its service life. These cover, for example, de-installation and decommissioning costs (in case of oil rigs or nuclear power stations) or rehabilitation costs of land sites”.

3.6.2 Application to offshore oil and gas

For offshore oil and gas platforms, decommissioning typically involves:

• Plugging and abandonment of wells
• Removal of platforms and surface facilities
• Removal or stabilisation of pipelines
• Environmental remediation of the site

The SEEA CF notes that for oil rigs, the original owner may no longer be an active business when decommissioning is required, creating challenges for cost recovery. The accounting treatment provides for several scenarios:

1. Terminal costs exceed accumulated provision — the shortfall is written off as depreciation when incurred
2. No provision made — terminal costs are treated as gross fixed capital formation and immediately depreciated
3. Terminal costs not incurred by operator — subsequent costs by other parties are treated as remedial costs

In practice, offshore energy decommissioning often involves complex ownership structures, including joint ventures and transfers of ownership during the asset’s life. While the accounting principles above apply regardless of ownership structure, compilers should document the ownership arrangements at the time of decommissioning and allocate costs to the responsible economic units accordingly. Where decommissioning obligations transfer with asset ownership, the present value of future decommissioning costs effectively reduces the transfer price of the asset.

3.6.3 Decommissioning of renewable energy infrastructure

Offshore wind and other renewable energy infrastructure also requires end-of-life management, though the obligations may differ from oil and gas:

Decommissioning decisions have implications for marine ecosystems that may colonise offshore structures during their operating lives. Platform structures and turbine foundations can function as artificial reefs, supporting marine biodiversity. Accounting for these ecosystem effects requires integration with ecosystem accounting approaches covered in TG-3.1 Asset Accounts and the broader ecosystem extent and condition accounts described in SEEA Ecosystem Accounting.

“Rigs-to-reefs” programmes that convert decommissioned platforms to permanent artificial reefs represent a transfer of assets rather than full removal. The accounting treatment should reflect:

• Reduction in produced asset value (platform as industrial asset)
• Potential creation or enhancement of ecosystem asset value (artificial reef)
• Any ongoing monitoring or management obligations

Whether a rigs-to-reefs structure qualifies as an ecosystem asset depends on whether it meets the SEEA EA criteria for ecosystem extent and condition: the structure must support a self-sustaining biological community over a defined spatial area and provide measurable ecosystem services. Where these criteria are met, the transition from produced asset to ecosystem asset represents a reclassification that should be recorded in the other changes in volume of assets account. Compilers should coordinate with ecosystem accounting teams (see SEEA EA Chapter 4 on ecosystem extent accounts) and document the criteria applied.

3.7 Worked Example: Coastal State Offshore Energy Accounts

This section presents a worked example demonstrating the compilation of offshore energy accounts for a hypothetical Coastal State. The example uses synthetic data to illustrate the full workflow from data collection through to integrated energy transition indicators. The example covers a five-year period (2020-2024) during which Coastal State transitions from offshore oil and gas dominance to renewable energy deployment.

3.7.1 Context and policy questions

Coastal State context:

• EEZ area: 150,000 km²
• Mature offshore oil and gas sector with declining reserves
• Offshore wind expansion target: 10 GW by 2030
• Emerging tidal energy pilot projects in high-current straits
• Policy goal: Net zero carbon by 2050 with offshore renewables providing 40% of electricity

Key policy questions informing account design:

1. What is the rate of depletion of offshore oil and gas reserves, and when will reserves be exhausted at current extraction rates?
2. What is the change in natural capital value as the offshore energy mix shifts from non-renewable to renewable resources?
3. What is the contribution of offshore energy to national GDP when adjusted for resource depletion?
4. How much has offshore renewable energy capacity expanded, and is the pace sufficient to meet 2030 targets?

3.7.2 Physical accounts: Offshore oil (Class A)

Table 4: Physical asset account for offshore oil (Class A), 2024 (million barrels)

Interpretation: Offshore oil reserves declined by 20 million barrels net during 2024. At the current extraction rate of 65 million barrels per year, remaining reserves will be exhausted in approximately 14 years (900 ÷ 65 = 13.8). This signals the need for economic diversification as oil reserves decline.

3.7.3 Physical accounts: Offshore wind

Table 5: Physical asset account for offshore wind capacity, 2024 (MW)

Interpretation: Offshore wind capacity increased by 1,120 MW net during 2024, representing 25% growth. Total installed capacity of 5,470 MW is 55% of the 2030 target (10,000 MW), requiring continued expansion at approximately 750 MW per year to reach the target. Capacity factor of 41% is consistent with international benchmarks for offshore wind.

3.7.4 Monetary valuation: Offshore oil

Table 6: Monetary asset account for offshore oil (Class A), 2024 (million USD)

Valuation assumptions:

• Oil price in situ: USD 30 per barrel (world oil price USD 75/barrel minus extraction costs USD 30/barrel, user costs USD 15/barrel)
• Discount rate: 7% real
• Average resource life: 14 years
• Resource rent calculation follows SEEA CF para. 5.194-5.213

Interpretation: The monetary value of offshore oil reserves declined by USD 400 million during 2024. Depletion of USD 1,950 million represents consumption of natural capital that should be deducted from GDP to calculate depletion-adjusted net domestic product (NDP). Price revaluations added USD 200 million due to strengthening of long-term oil price expectations.

3.7.5 Monetary valuation: Offshore wind

Table 7: Monetary asset account for offshore wind resources, 2024 (million USD)

Valuation assumptions:

Interpretation: The value of offshore wind resources increased by USD 2,980 million during 2024, driven by capacity additions (1,200 MW × USD 2.2 million/MW = USD 2,640 million) and revaluations due to improved long-term electricity price outlook (USD 420 million). Unlike oil reserves, there is no depletion of renewable energy resources since the wind itself is not consumed.

3.7.6 Integrated energy transition indicators

Table 8: Coastal State offshore energy transition dashboard, 2020-2024

Key insights from integrated accounts:

The offshore energy accounts developed in this example feed into broader ocean accounting and policy frameworks:

Upward to policy (Section 1 circulars):

• TG-1.1 National Ocean Budgets — Total offshore energy asset value (USD 38.4 billion in 2024) appears on the ocean natural capital balance sheet, informing budget allocation decisions
• TG-2.5 Structure and Function of the Ocean Economy — Offshore energy contribution to ocean GDP (USD 5.0 billion gross, USD 3.1 billion depletion-adjusted) contributes to measuring ocean economy size
• TG-2.1 Aggregate Biophysical Indicators of Environmental State — Energy transition metrics (renewable share of assets, renewable share of production) track progress toward net zero targets

Downward to data (Section 4 circulars):

• TG-4.3 Administrative Data Sources — Oil production data sourced from petroleum licensing authority, and offshore wind capacity from transmission system operator registers
• TG-4.1 Remote Sensing and Geospatial Data — Lease area boundaries and BSU assignments enable spatial disaggregation of energy accounts

Lateral to other accounts (Section 3 circulars):

• TG-3.3 Economic Activity Relevant to the Ocean — Offshore oil extraction (ISIC 0610) and offshore wind generation (ISIC 3510) classified within ocean economy
• TG-3.4 Flows from Economy to Environment — Oil and gas extraction generated 4.2 million tonnes CO2-equivalent emissions in 2024, attributed to marine spatial units where platforms operate