Definitions for technical acronyms used across the Net Zero Playbook pathways. Click any linked acronym on a pathway page to jump directly to its definition here.
One of the major voluntary carbon offset registries in the US (operated by Winrock International), certifying and tracking carbon credits for projects including forestry, methane capture, and agriculture. ACR-issued credits are used in both voluntary and compliance markets.
The EPA's reference document providing default emission factors for a wide range of stationary and mobile sources. Used in GHG inventories when measured data or supplier-specific factors are unavailable. Covers combustion processes, industrial processes, and waste management.
The professional society that publishes widely adopted building energy codes and standards, including ASHRAE 90.1 (energy efficiency for commercial buildings) and ASHRAE 55 (thermal comfort). ASHRAE standards form the basis of many local building codes and green certification requirements.
A technology combining biomass energy production with carbon capture and geological storage. Because biomass absorbs CO₂ as it grows and that CO₂ is then stored rather than re-emitted, BECCS can generate electricity or heat while producing net negative emissions — making it a key tool in deep decarbonization scenarios.
A computer-based control system installed in buildings that monitors and controls mechanical and electrical equipment — including HVAC, lighting, power, fire, and security systems. Modern BMS platforms integrate with IoT sensors and grid signals to optimize energy use and enable demand response participation.
The process of capturing CO₂ emissions at the point of production (e.g., a power plant or industrial facility), then transporting and storing it in geological formations such as depleted oil and gas fields or saline aquifers. CCS does not utilize the captured CO₂ (cf. CCUS).
Technologies that capture CO₂ from industrial processes, power generation, or the atmosphere, then either store it permanently underground or use it as a feedstock (e.g., in synthetic fuels or chemicals). The "utilization" component distinguishes CCUS from CCS alone. The US Section 45Q tax credit directly incentivizes CCUS deployment.
A global nonprofit that runs the world's largest environmental disclosure system. Over 23,000 companies disclose their GHG emissions, water security, and deforestation risks through CDP annually, responding to requests from 740+ institutional investors. CDP scores (A–D) are widely used by investors and supply chain customers to evaluate sustainability performance.
Electricity generated without direct greenhouse gas emissions — including solar, wind, nuclear, and geothermal. Used especially in the context of 24/7 CFE procurement, where companies commit to matching every hour of their consumption with a carbon-free source in the same grid region, a stricter standard than annual renewable energy certificates.
Also called cogeneration, CHP simultaneously produces electricity and useful thermal energy (steam or hot water) from a single fuel source. By capturing heat that conventional generation discards, CHP systems achieve overall efficiencies of 65–85%, compared to ~35% for conventional power plants. CHP can run on natural gas, biogas, hydrogen, or waste heat.
EU legislation (effective 2024–2026 in phases) requiring large companies and listed SMEs operating in Europe to report detailed sustainability information using the European Sustainability Reporting Standards (ESRS). CSRD dramatically expands the scope of the earlier Non-Financial Reporting Directive, covering ~50,000 companies with Scope 1, 2, and 3 emissions disclosure.
Technology that removes CO₂ directly from the ambient atmosphere using chemical processes (liquid solvent or solid sorbent systems). Unlike point-source CCS, DAC can be sited anywhere and achieves genuine carbon removal. Current costs are $300–600/tonne; DOE's DAC Hub program is targeting $100/tonne by 2030.
Software platforms used by utilities and grid operators to monitor, coordinate, and optimize distributed energy resources (solar, storage, EVs, demand response) in real time. DERMS enables aggregation of behind-the-meter assets into virtual power plants and manages two-way power flows on distribution networks.
Programs that incentivize electricity consumers to voluntarily reduce or shift their power use during periods of peak grid demand or high prices. DR participants typically receive bill credits, capacity payments, or energy payments. Advanced DR uses automated building controls and smart inverters to respond in seconds to grid signals.
A market-based instrument that certifies one MWh of electricity was generated from a specific energy source. RECs (US), Guarantees of Origin (Europe), and I-RECs (international) are all types of EACs. Retiring an EAC allows a buyer to claim the environmental attributes of that generation for Scope 2 market-based reporting.
An economic modeling approach that extends traditional input-output analysis with environmental data to estimate the emissions associated with goods and services across entire supply chains. Used as a spend-based method for Scope 3 Category 1 (Purchased Goods and Services) when supplier-specific data is unavailable. The USEEIO model from EPA is a commonly used source.
EPA's comprehensive database of US electricity generation and its associated environmental characteristics, published annually. eGRID provides grid emission factors (lbs CO₂e/MWh) by subregion — the standard data source for calculating location-based Scope 2 emissions and assessing the carbon intensity of specific grid regions for REC purchases.
A document rating a building's energy efficiency on a standardized scale (A–G in the EU/UK, similar systems elsewhere). EPCs are mandatory in many jurisdictions when buildings are sold, rented, or constructed, and set minimum performance thresholds. EPC ratings increasingly influence property values and financing terms.
The independent system operator (ISO) managing the flow of electric power across most of Texas — one of the largest power grids in the US, serving ~90% of the state's electric load. ERCOT operates a nodal market and manages a separate REC tracking registry (ERCOT RECS) for Texas renewable energy claims.
The detailed reporting standards adopted under the EU's CSRD, developed by EFRAG. ESRS define exactly what companies must disclose on climate (ESRS E1), biodiversity, water, circular economy, workforce, and governance. ESRS E1 requires Scope 1, 2, and 3 GHG disclosures, transition plan details, and climate risk assessments aligned with TCFD.
A measure of building energy consumption per unit of floor area per year, expressed as kBtu/sf/yr (US) or kWh/m²/yr (international). EUI normalizes energy use to enable benchmarking between buildings of different sizes. ENERGY STAR Portfolio Manager uses EUI to score buildings; ASHRAE 90.1 sets target EUIs by building type.
The regulatory and technical term for EV charging equipment — the hardware that safely delivers electricity from the grid to an electric vehicle. EVSE encompasses Level 1 (120V household outlet), Level 2 (240V), and DC fast charging (DCFC) units. NEVI program funding targets DCFC EVSE deployment along Interstate corridors.
Software or algorithmic systems that automatically identify equipment faults, performance degradation, and operational inefficiencies in building systems (especially HVAC). FDD analyzes sensor data against baseline performance models to flag issues before they cause energy waste or equipment failure, often integrated into BMS platforms.
A detailed engineering phase for major capital projects (such as CCUS facilities or industrial electrification) that occurs after conceptual design and before the Final Investment Decision (FID). FEED studies define equipment specifications, cost estimates (typically ±10–15%), schedules, and risk profiles that underpin project financing and permitting.
An SBTi target category for companies with significant land-use emissions (agriculture, forestry, food, beverage, tobacco). FLAG targets require separate reduction goals for land-based emissions alongside the company's broader Scope 1–3 targets, using the SBTi FLAG guidance to account for the unique carbon dynamics of biological systems.
Buildings that use smart controls, flexible loads, and on-site storage to dynamically respond to grid signals — reducing peak demand, providing demand response, and integrating variable renewables — while maintaining energy efficiency. GEBs earn revenue from grid services while reducing their own energy costs and emissions.
An industry body that develops the GLEC Framework — the global standard for calculating and reporting GHG emissions from freight transport and logistics operations. The GLEC Framework is the methodology recognized by the GHG Protocol for Scope 3 Categories 4 (upstream) and 9 (downstream) transportation emissions.
The European equivalent of a Renewable Energy Certificate (REC), certifying that one MWh of electricity was generated from a renewable source. GOs are issued by national registries (RECS International coordinates cross-border transfers) and used for Scope 2 market-based reporting. Unlike US RECs, GOs can cover electricity, heating, and cooling.
The international standards organization providing the world's most widely used sustainability reporting framework. GRI Standards cover economic, environmental, and social topics using a modular structure: Universal Standards (GRI 1–3) apply to all organizations; Topic Standards address specific issues like GHG emissions (GRI 305), energy (GRI 302), and waste (GRI 306).
A measure of how much heat a greenhouse gas traps in the atmosphere over a given time horizon (typically 100 years), relative to CO₂ (GWP = 1). For example, methane has a GWP-100 of ~30 and HFC refrigerants can exceed 10,000. GWP values are used to convert different GHGs to a common CO₂-equivalent (CO₂e) unit for inventory reporting.
An electric water heater that moves heat from the surrounding air into the water rather than generating heat directly from an electric resistance element. HPWHs are 2–4× more efficient than conventional electric resistance heaters (coefficient of performance of 2–4), making them a key electrification technology for commercial and residential building decarbonization.
The integrated systems used to regulate indoor climate in buildings — typically the single largest energy end use in commercial buildings, accounting for 30–50% of building energy consumption. HVAC decarbonization pathways include heat pump electrification, variable refrigerant flow systems, demand-controlled ventilation, and thermal energy storage.
A company-assigned price on carbon emissions used in internal investment analysis, capital allocation, and procurement decisions. ICPs come in two main forms: shadow prices (applied to decisions without actual money transfer) and internal carbon fees (actual funds collected and recycled to fund decarbonization projects). CDP data shows median ICP around $25–50/tonne CO₂e.
An independent governance body that sets quality thresholds for voluntary carbon credits through its Core Carbon Principles (CCPs). Credits meeting CCP requirements can carry the ICVCM label, indicating additionality, permanence, robust MRV, and sustainable development co-benefits. The ICVCM was established by the Taskforce on Scaling Voluntary Carbon Markets.
A model building code published every three years by the International Code Council (ICC) establishing minimum energy efficiency requirements for residential and commercial buildings in the US. Most US states adopt some version of the IECC (often with amendments); IECC compliance is typically required for building permits and is a baseline for LEED and ENERGY STAR certifications.
US federal legislation signed in August 2022 providing approximately $369 billion in climate and clean energy investments — the largest climate policy in US history. Key IRA provisions include the expanded Investment Tax Credit (ITC, Section 48), Production Tax Credit (PTC, Section 45), 45Q for carbon capture, 45V for clean hydrogen, and the 48C advanced manufacturing credit, many extended through 2032 with bonus adders for domestic content and energy communities.
A US federal tax credit under IRC Section 48 (IRA-expanded) providing a percentage of qualified clean energy investment costs — typically 30% base with potential bonus credits of 10% each for domestic content and energy community siting. Eligible technologies include solar, wind, storage, fuel cells, CHP, geothermal, and microgrid controllers. The IRA also enables credit transferability and direct pay for tax-exempt entities.
A business model where a provider delivers LED lighting, controls, installation, maintenance, and monitoring for a monthly fee rather than a capital purchase. LaaS eliminates upfront capital requirements for lighting upgrades, bundles performance guarantees, and often includes energy savings guarantees — enabling building owners to improve efficiency without balance-sheet investment.
A systematic methodology for assessing the environmental impacts of a product, process, or service across its entire life cycle — from raw material extraction through manufacturing, use, and end-of-life disposal. LCA is standardized under ISO 14040/14044. In the GHG context, LCA supports Scope 3 product footprinting, Environmental Product Declarations (EPDs), and supplier engagement.
California's regulation (administered by CARB) establishing a carbon intensity-based market for transportation fuels. Fuels with a lower carbon intensity than the standard generate LCFS credits; higher-CI fuels generate deficits. RNG produced from dairy digesters or landfills can achieve highly negative carbon intensities, generating valuable LCFS credits that significantly improve project economics.
The most widely used green building rating system worldwide, developed by the US Green Building Council (USGBC). LEED certifications (Certified, Silver, Gold, Platinum) are awarded based on points across categories including energy efficiency, water, materials, indoor quality, and site. LEED v4.1 requires actual performance data and life cycle assessment for many credits.
A transportation model that integrates multiple modes of public and private transport — including transit, rideshare, bikeshare, and EV rental — into a single digital platform with flexible subscription or pay-per-use access. MaaS platforms can reduce personal vehicle ownership, lower Scope 3 commuting emissions, and support corporate travel demand management programs.
The US federal tax depreciation system allowing accelerated deductions for qualifying business assets. Most clean energy equipment — solar, storage, EV chargers, CHP — qualifies for 5-year MACRS depreciation (vs. 39 years for commercial real estate), significantly improving project economics. Bonus depreciation provisions under the Tax Cuts and Jobs Act further accelerated deductions to 100% in the year of installation (phasing down after 2022).
The renewable energy certificate tracking registry serving the Midwest US (Illinois, Wisconsin, Minnesota, North Dakota, South Dakota, and others). M-RETS issues, transfers, and retires RECs for renewable generation in its jurisdiction. Corporate buyers in Midwest markets use M-RETS to substantiate Scope 2 market-based renewable energy claims.
An open-standard communication protocol developed by Pacific Northwest National Laboratory (PNNL) enabling interoperability between energy storage systems and grid management software. MESA standards (MESA-Device and MESA-ESS) allow storage hardware from different manufacturers to communicate with utility DERMS and building energy management systems using common data models.
The process of measuring GHG emissions (or reductions), reporting them in a standardized format, and having them independently verified by a third party. MRV underpins carbon credit credibility: offset projects must establish robust MRV protocols to ensure reported reductions are real, additional, and permanent. ISO 14064-3 and IPCC guidelines define MRV requirements for different contexts.
A leading provider of investment research tools, global equity indices, and ESG ratings used by institutional investors worldwide. MSCI ESG Ratings assess companies on material ESG risks and opportunities on a scale from AAA to CCC. Companies with strong MSCI ESG ratings benefit from improved access to ESG-mandated investment capital.
A $5 billion federal program (funded by the 2021 Infrastructure Investment and Jobs Act) building a national network of EV fast-charging stations along Interstate highways and in underserved communities. NEVI requires DCFC stations at 50-mile intervals along designated corridors, with minimum 4 charging ports at 150 kW each, and imposes domestic content and open-network requirements.
A group of reactive air pollutants — primarily nitric oxide (NO) and nitrogen dioxide (NO₂) — produced during high-temperature combustion of fossil fuels. NOx are regulated criteria pollutants under the Clean Air Act and precursors to ground-level ozone (smog) and fine particulate matter (PM2.5). Industrial CHP and CCUS systems typically require NOx controls to meet air permit limits.
A financial metric calculating the difference between the present value of cash inflows and outflows over a project's life, discounted at the cost of capital. A positive NPV indicates the project creates value. NPV analysis is used to assess clean energy and decarbonization investments, incorporating factors like energy savings, tax credits, carbon price, and avoided cost of future carbon regulations.
A financing mechanism allowing property owners to fund energy efficiency, renewable energy, and water conservation improvements through an assessment added to their property tax bill rather than a traditional loan. PACE financing is repaid over 10–30 years and transfers with the property upon sale. Commercial PACE (C-PACE) is available in 35+ US states and can cover 100% of project costs.
A global industry-led partnership developing standardized GHG accounting methodologies for financial institutions to measure and disclose the emissions associated with their loans and investments (financed emissions). The PCAF Standard is aligned with the GHG Protocol and covers asset classes including listed equity, corporate bonds, project finance, and mortgages.
A key electrochemical technology used in both hydrogen production (PEM electrolyzers) and power generation (PEM fuel cells). PEM electrolyzers split water into hydrogen and oxygen using electricity; they operate at low temperatures, respond rapidly to variable renewable power, and produce high-purity hydrogen — making them the dominant technology for green hydrogen production.
A long-term contract (typically 10–25 years) between an electricity generator and a buyer (offtaker) setting the price and terms for electricity delivery. Corporate PPAs come in two main forms: physical PPAs (actual electricity delivered to the buyer's facility) and virtual/financial PPAs (also called VPPAs, where the buyer receives the RECs and a financial settlement based on market price differences). PPAs are the dominant mechanism for large corporate renewable procurement.
A US federal tax credit under IRC Section 45 (IRA-expanded) providing a per-kWh incentive for electricity generated by qualified renewable energy facilities — typically wind, geothermal, and (under IRA) solar. The IRA PTC is approximately 2.75¢/kWh (inflation-adjusted) for 10 years from project commissioning, with bonus adders for domestic content and energy communities. Projects can elect either PTC or ITC, not both.
A market-based instrument representing one MWh of electricity generated from a renewable source. RECs are issued in the US by tracking registries (WREGIS, M-RETS, PJM-GATS, ERCOT RECS, NEPOOL GIS) and can be traded separately from the physical electricity (unbundled RECs). Retiring a REC allows a buyer to claim the renewable attribute for Scope 2 market-based reporting or voluntary clean energy claims.
A UN framework (under the UNFCCC) that incentivizes developing countries to reduce deforestation and forest degradation by assigning financial value to forest carbon stocks. The "+" covers the roles of forest conservation, sustainable management, and enhancement of carbon stocks. REDD+ credits are used in voluntary carbon markets, though quality concerns about additionality and permanence have increased scrutiny of forest offset projects.
A credit generated under the EPA's Renewable Fuel Standard (RFS) program when qualifying renewable fuels — including renewable natural gas (RNG), cellulosic ethanol, and biodiesel — are produced or imported. Obligated parties (petroleum refiners and importers) must acquire and retire RINs to demonstrate compliance with annual blending mandates. RINs are a major revenue stream for RNG projects, significantly improving their economics.
Also called biomethane, RNG is pipeline-quality gas produced by upgrading biogas from organic waste streams — including landfills, dairy digesters, municipal wastewater, and food waste — to remove CO₂, water, and impurities. Chemically identical to fossil natural gas, RNG can be injected into existing pipelines or used as vehicle fuel. When produced from waste streams, RNG has a negative or near-zero lifecycle carbon intensity.
An organization (now part of the IFRS Foundation alongside ISSB) that develops industry-specific sustainability accounting standards for use by public companies in disclosures to investors. SASB Standards identify the subset of ESG topics most likely to be financially material for each of 77 industries, covering metrics for energy, emissions, and related topics. SASB is increasingly integrated with TCFD and ISSB frameworks.
A collaboration between CDP, UNGC, WRI, and WWF that defines and promotes best practices for corporate GHG reduction targets consistent with climate science (1.5°C or well-below 2°C pathways). SBTi validates corporate targets across Scope 1, 2, and 3 emissions; over 7,000 companies have committed globally. SBTi's Corporate Net-Zero Standard requires 90%+ absolute reductions and restricts reliance on offsets before achieving deep cuts.
An estimate (in $/tonne CO₂) of the present-value economic damages caused by emitting one additional tonne of CO₂, accounting for impacts on agriculture, human health, coastal flooding, and ecosystem services. The Biden administration estimated the US SCC at ~$190/tonne CO₂; the EPA's 2023 update raised it to $120–340/tonne. Companies use SCC to calibrate internal carbon prices and justify decarbonization investments.
The US federal agency regulating capital markets and public company disclosures. The SEC's 2024 Climate Disclosure Rules (effective for large accelerated filers from FY2025) require publicly traded companies to disclose Scope 1 and 2 GHG emissions, material climate risks, and climate-related governance — representing the first mandatory US federal climate reporting requirement for public companies.
The dominant industrial process for producing hydrogen, using natural gas (methane) reacted with steam over a catalyst at high temperature to produce hydrogen and CO₂. Without carbon capture, SMR produces "grey" hydrogen with ~10–12 kg CO₂/kg H₂. Coupling SMR with CCS produces "blue" hydrogen with significantly lower lifecycle emissions, though methane leakage is a key variable.
A high-temperature (700–900°C) electrolyzer technology for hydrogen production that can use both electricity and heat as energy inputs. Because a portion of the energy comes from heat rather than electricity, SOECs can achieve higher efficiencies than PEM or alkaline electrolyzers — making them well-suited for integration with industrial waste heat sources, nuclear plants, or concentrated solar power.
A high-efficiency electrochemical device operating at 600–1000°C that converts fuel (hydrogen, natural gas, or biogas) directly into electricity and heat without combustion. SOFCs achieve electrical efficiencies of 50–60% and total CHP efficiencies above 85%, significantly higher than combustion-based generation. Their high operating temperature also makes them well-suited for industrial process heat applications.
A technology that stores heat or cold energy over months for use in a different season — typically charging in summer (storing cold or heat) and discharging in winter or summer respectively. STES systems often use underground aquifers, boreholes, or insulated pits as the storage medium. Used in district heating/cooling networks and industrial facilities to shift thermal loads and improve overall system efficiency.
US federal legislation (2002) establishing internal control and auditing requirements for public companies following corporate accounting scandals. SOX Section 302 requires executive certification of financial disclosures; Section 404 requires management and external auditor assessment of internal controls. As climate disclosures increasingly fall within SEC reporting requirements, SOX-equivalent internal controls for GHG data are expected by regulators and auditors.
An industry-led body (established by the Financial Stability Board) that developed voluntary recommendations for disclosing climate-related financial risks and opportunities, organized around four pillars: Governance, Strategy, Risk Management, and Metrics & Targets. TCFD recommendations have been adopted by 4,000+ organizations and form the basis of mandatory disclosure regimes including CSRD, SEC climate rules, and the UK's mandatory TCFD reporting (now ISSB-aligned).
Strategies and policies aimed at reducing vehicle trips or shifting them to lower-carbon modes of transport. TDM programs for employers may include transit subsidies, vanpool programs, bike infrastructure, remote work policies, flexible scheduling, and parking pricing. TDM addresses Scope 3 Category 7 (employee commuting) and Category 6 (business travel) emissions.
A framework (finalized 2023, parallel to TCFD) for companies and financial institutions to assess, manage, and disclose nature-related risks and impacts — including biodiversity loss, land use, freshwater, and ocean health. TNFD uses a LEAP (Locate, Evaluate, Assess, Prepare) approach and is increasingly integrated with CSRD's biodiversity reporting requirements.
An electricity rate structure that charges different prices depending on when electricity is consumed — typically higher during peak demand periods (afternoons/evenings) and lower during off-peak hours (nights, weekends). TOU rates incentivize load shifting and EV charging optimization. Under TOU, energy storage and demand response programs can substantially reduce electricity bills for commercial customers.
A bidirectional charging technology that allows EV batteries to discharge stored electricity back into a building's electrical system (rather than to the grid). V2B enables EVs to serve as mobile energy storage — powering building loads during peak hours, providing backup power during outages, and integrating with building energy management systems. V2B requires bidirectional EVSE and compatible vehicle onboard chargers.
Bidirectional EV charging technology enabling EVs to discharge stored electricity back to the electrical grid. V2G allows EV batteries to provide grid services — frequency regulation, peak shaving, demand response — generating revenue for vehicle owners. Requires bidirectional EVSE (DC fast chargers with V2G capability) and grid interconnection agreements. Significant V2G deployments underway in the Netherlands, Japan, and California.
An electronic controller that adjusts the rotational speed of AC electric motors by varying the frequency and voltage of the power supplied to them. Because pump and fan power scales with the cube of speed, even modest speed reductions yield large energy savings. VFDs are one of the highest-ROI energy efficiency investments for industrial motors, HVAC systems, and compressed air equipment.
A high-performance building insulation product consisting of a rigid core material enclosed in an airtight membrane with the air evacuated to create a near-vacuum. VIPs achieve thermal conductivities of 0.003–0.008 W/(m·K) — 5–10× lower than conventional insulation — enabling high insulating performance in very thin profiles. Used where space constraints limit conventional insulation thickness (walls, floors, cold storage).
A software-coordinated network of distributed energy resources — solar generation, battery storage, EV batteries, smart thermostats, and demand response loads — aggregated to function as a dispatchable resource equivalent to a conventional power plant. VPPs participate in wholesale electricity markets, providing capacity, frequency regulation, and energy arbitrage services while generating revenue for participants and helping balance the grid.
The renewable energy certificate tracking registry for the Western Interconnection — covering the Western US, Canada, and Baja California. WREGIS issues, tracks, and retires RECs for renewable generation in its jurisdiction, including California (where WREGIS RECs are required for CPUC Renewables Portfolio Standard compliance). Corporate buyers in Western markets use WREGIS to substantiate Scope 2 market-based claims and RPS compliance.
A structured data format used in regulatory filings to make financial and sustainability data machine-readable and directly comparable across companies. The SEC requires XBRL tagging for financial disclosures; CSRD and ESRS require iXBRL (Inline XBRL) for sustainability reports submitted via the European Single Access Point (ESAP). XBRL tagging allows regulators, investors, and analysts to process sustainability data at scale without manual re-entry.