EDGE-Expert EDGE Excellence in Design for Greater Efficiencies (EDGE Expert) Exam Free Practice Exam Questions (2026 Updated)

According to the CBCI EDGE curriculum, natural ventilation is a passive design strategy that enhances indoor comfort by allowing fresh outdoor air to enter and circulate through a building without the use of mechanical systems. When properly designed, natural ventilation utilizes pressure differences created by wind and temperature variations, such as cross ventilation and stack effect, to drive airflow. This can reduce indoor temperatures and improve air quality without consuming electrical energy for fans or mechanical equipment.

In contrast, heat recovery ventilators and energy recovery ventilators are mechanical systems that use fans to move air through heat exchange cores. Although they are energy-efficient compared to conventional mechanical ventilation, they still require electrical power to operate. Similarly, continuously running mechanical ventilation systems depend entirely on powered fans and therefore consume energy.

EDGE promotes passive design measures, including natural ventilation where climate conditions permit, as a means to reduce cooling loads and improve energy performance. Because it operates without mechanical energy input, natural ventilation is the only option listed that meets the condition of improving comfort without using any energy.

Variable Refrigerant Volume (VRV) or Variable Refrigerant Flow (VRF) systems are evaluated in EDGE for their energy efficiency in HVAC applications. The EDGE User Guide explains their application: "VRV/VRF systems are best suited for multizone spaces, as they can simultaneously heat and cool different zones by varying the refrigerant flow, making them ideal for buildings with diverse thermal loads, such as hotels, offices, or hospitals with multiple rooms" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). Option C, multizone space, aligns with this description, as VRV/VRF systems excel in managing varied temperature needs across multiple zones. Option A (single zone space) and Option B (single zone office space) are incorrect, as VRV/VRF systems are less efficient for single zones: "For single zone spaces, simpler systems like split units are more appropriate, as VRV/VRF systems are designed for multizone control" (EDGE Methodology Report Version 2.0, Section 5.1: Energy Efficiency Metrics). Option D (meeting space) is too specific and typically a single zone, not leveraging VRV/VRF’s multizone capability: "Meeting spaces are often single zones, where VRV/VRF systems may be oversized" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). Thus, VRV/VRF systems are best used for multizone spaces (Option C).

The EDGE software requires users to select a building type (typology) to model resource consumption accurately, and the choice depends on the scope of the certification. In this scenario, a tenant on the third floor (an office floor) of a medium-rise building seeks EDGE certification. The EDGE User Guide provides guidance on selecting building types for tenant spaces: "When a tenant within a larger building seeks EDGE certification, the building type should reflect the tenant’s space. For an office tenant on the third floor of a mixed-use building, the ‘Office’ typology should be selected, as the certification applies only to the tenant’s space, not the entire building, unless the whole building is being certified" (EDGE User Guide, Section 2.2: Project Setup). Option A, Office, aligns with this guidance, as the tenant’s space is an office. Option B (Retail) is incorrect, as the retail floors are on the first two levels, not the third: "Retail typology would apply if the tenant space were on the retail floors, not the office floors" (EDGE User Guide, Section 2.2: Project Setup). Option C (Mixed-use) is also incorrect, as this typology applies to the entire building, not a single tenant space: "Mixed-use typology is used when the entire building, including all uses (e.g., retail and offices), is being certified, not for individual tenant spaces" (EDGE Methodology Report Version 2.0, Section 2.1: Calculation Approach). Option D (Core and Shell) is typically used for buildings certified up to the core and shell stage, not for tenant fit-outs: "Core and Shell typology applies to buildings certified without tenant fit-outs, focusing on the building envelope and systems, not individual tenant spaces like an office" (EDGE Certification Protocol, Section 1.2: Scope of EDGE Standard). The EDGE User Guide further clarifies: "For tenant-led certifications, the typology should match the tenant’s use—e.g., ‘Office’ for an office tenant—even if the building has multiple uses, ensuring the Base Case reflects the tenant’s specific consumption patterns” (EDGE User Guide, Section 2.2: Project Setup). Since the tenant on the third floor operates an office, the Office typology (Option A) is the correct choice for EDGE certification.

EDGE Auditors must meet specific requirements to maintain their licensed status, ensuring they remain active and competent in their role. The EDGE Expert and Auditor Protocols provide detailed guidance: "To maintain their licensed status, EDGE Auditors must undertake at least one building project audit every two years. This requirement ensures that Auditors remain actively engaged in the certification process and maintain their practical experience in verifying EDGE projects" (EDGE Expert and Auditor Protocols, Section 5.1: Maintaining Auditor Status). Option A, undertake at least one building project audit every two years, directly aligns with this requirement. Option B (attend refresher training for at least two hours every two years) and Option C (attend refresher training for at least two hours every three years) are incorrect, as the protocols specify a different training requirement: "EDGE Auditors must attend refresher training as required by IFC, typically every three years, but the duration is not specified as a minimum of two hours; the focus is on completing the training, not the exact hours" (EDGE Expert and Auditor Protocols, Section 5.1: Maintaining Auditor Status). Option D (undertake at least one building project audit every three years) is also incorrect, as the required frequency is every two years, not three: "A three-year interval for audits does not meet the requirement of one audit every two years, which is necessary to ensure ongoing competence" (EDGE Expert and Auditor Protocols, Section 5.1: Maintaining Auditor Status). The EDGE User Guide supports this by stating: "Auditors maintain their status by conducting at least one audit every two years, ensuring they stay familiar with EDGE standards and procedures through active practice" (EDGE User Guide, Section 6.5: Working with EDGE Auditors). Additionally, the protocols note: "Failure to conduct an audit within two years may result in a lapse of Auditor status, requiring recertification through additional training or re-examination" (EDGE Expert and Auditor Protocols, Section 5.2: Recertification Conditions). Thus, undertaking at least one audit every two years (Option A) is the correct requirement for maintaining EDGE Auditor status.

Insulation materials in EDGE are evaluated for their thermal performance and embodied energy as part of materials efficiency measures. The EDGE User Guide lists common insulation options: "In EDGE, insulation materials for walls, roofs, and floors include mineral wool, polyurethane, polystyrene, and fiberglass, which are selected for their low thermal conductivity and availability in most markets" (EDGE User Guide, Section 7.2: Materials Efficiency Measures). Options A (mineral wool), B (polyurethane), and D (polystyrene) are explicitly mentioned as insulation materials in EDGE. Option C, polypropylene, is not listed as an insulation material, as confirmed by the EDGE Methodology Report: "Polypropylene is a plastic material often used in packaging or pipes, but it is not recognized in EDGE as an insulation material due to its poor thermal resistance compared to standard insulation options like polystyrene or polyurethane" (EDGE Methodology Report Version 2.0, Section 6.1: Embodied Energy in Materials). The EDGE software’s material database further excludes polypropylene from insulation options, focusing instead on materials with established thermal properties for building envelopes. Thus, polypropylene (Option C) is not an insulation option in EDGE.

The EDGE software uses a simplified approach to calculate energy consumption, focusing on accessibility and speed for users in emerging markets. The EDGE Methodology Report explains the calculation method: "Energy consumption in EDGE is calculated using steady state calculations, which assume constant conditions over a period to estimate energy use for heating, cooling, lighting, and other systems. This method simplifies the modeling process while providing sufficiently accurate results for the purposes of EDGE certification" (EDGE Methodology Report Version 2.0, Section 5.2: Energy Calculation Methods). Option B, steady state calculations, directly matches this approach. Option A (hourly simulation) is incorrect, as EDGE does not use dynamic simulations: "EDGE does not employ hourly simulations, which are more complex and resource-intensive, as the goal is to provide a fast and simple tool" (EDGE User Guide, Section 2.1: EDGE Software Overview). Option C (quasi-steady state calculations) is also incorrect, as EDGE does not use this intermediate method: "Quasi-steady state methods, which account for some dynamic effects, are not used in EDGE to maintain simplicity" (EDGE Methodology Report Version 2.0, Section 5.2: Energy Calculation Methods). Option D (cooling and heating degree days) is a metric used to estimate climate impact, not the calculation method: "Degree days are inputs to the steady state calculations, not the method itself" (EDGE User Guide, Section 3.2: Climate Data Inputs). Thus, steady state calculations (Option B) are used for energy consumption in EDGE.

In the CBCI EDGE curriculum, the EDGE Baseline is not fixed permanently because construction practices, typical system efficiencies, and national or city regulations evolve over time. To ensure that EDGE continues to represent a realistic and fair comparison against “standard practice” in each location, the EDGE Baseline is periodically reviewed and updated. The curriculum explains that baseline reviews are undertaken every 3 to 5 years when needed, and this review can include updates to the geographic coverage of EDGE, such as adding new countries or refining baselines where market conditions or codes have changed.

This review cycle helps maintain the credibility of the 20 percent savings thresholds by making sure the baseline remains aligned with what is commonly built in a given market. If baselines were updated too frequently, it would create instability for project planning; if updated too rarely, the baseline could become outdated and no longer reflect typical practice. The 3 to 5 year interval balances stability with relevance, ensuring that EDGE benchmarking stays accurate across different regions and over time.

The EDGE certification process involves specific steps and fees, including a registration fee, to formally enter a project into the certification system. The EDGE Certification Protocol outlines the timing of the registration fee: "The registration fee must be paid prior to registration of the project in the EDGE system. This fee is required to activate the project in the EDGE App, allowing the Client to begin the self-assessment process and proceed toward certification" (EDGE Certification Protocol, Section 2.1: Registration). Option B, prior to registration, directly matches this requirement, as payment is a prerequisite for starting the certification process. Option A (prior to site audit) is incorrect, as the site audit occurs later, at the post-construction stage: "The site audit takes place after practical completion, well after registration, so the registration fee is not tied to this stage" (EDGE Certification Protocol, Section 3.4: Post-Construction Requirements). Option C (after the registration) is also incorrect, as payment must precede registration: "Registration cannot be completed without payment of the registration fee, ensuring the project is officially entered into the system" (EDGE User Guide, Section 6.1: Project Preparation). Option D (after certification has been awarded) is wrong, as certification occurs at the end of the process, after registration and audits: "Certification fees may be paid after certification, but the registration fee is required at the outset, before any assessment begins" (EDGE Certification Protocol, Section 3.3: Certification Decision). The EDGE User Guide further clarifies: "Paying the registration fee prior to registration ensures that the project is formally recognized by the EDGE system, enabling access to the software and certification resources" (EDGE User Guide, Section 6.1: Project Preparation). Thus, the registration fee must be paid prior to registration (Option B).

The EDGE audit process requires that the documentation submitted by the Client accurately reflects the self-assessment in the EDGE software, ensuring consistency and transparency. The EDGE Expert and Auditor Protocols address discrepancies in documentation: "If an EDGE Auditor identifies a discrepancy between the submitted documentation and the self-assessment PDF, such as measures being claimed that were not selected in the EDGE software, the Auditor must inform the Client to update the EDGE software to reflect the correct measures and prepare a new PDF for submission. This ensures that the audit is based on an accurate representation of the project’s claims" (EDGE Expert and Auditor Protocols, Section 4.2: Evidence Verification). Option C, inform the Client to update the EDGE software and prepare a new PDF, directly aligns with this protocol, as it corrects the error at the source and ensures the self-assessment matches the claimed measures. Option A (ask for advice from the EDGE Partner) is unnecessary, as the protocol provides clear guidance: "Auditors are expected to follow standard procedures for discrepancies without needing to consult the EDGE Partner, unless the issue involves a policy interpretation beyond the protocols" (EDGE Expert and Auditor Protocols, Section 4.1: Audit Process). Option B (modify the self-assessment and submit) is unethical and prohibited, as Auditors cannot alter the Client’s submission: "The Auditor must not modify the Client’s self-assessment in the EDGE software, as this compromises the independence of the audit process; the Client is responsible for updating the assessment" (EDGE Certification Protocol, Section 3.2: Audit Requirements). Option D (ignore the error on PDF) is also incorrect, as ignoring discrepancies violates audit integrity: "All discrepancies between the PDF and submitted documents must be resolved before the audit proceeds, as ignoring errors could lead to incorrect certification outcomes" (EDGE Expert and Auditor Protocols, Section 4.2: Evidence Verification). The EDGE User Guide further reinforces: "The self-assessment PDF must accurately reflect the measures selected in the EDGE software, and any mismatch requires the Client to revise the assessment to ensure a fair and transparent audit" (EDGE User Guide, Section 6.2: Documentation Requirements). Thus, the Auditor should inform the Client to update the software and prepare a new PDF (Option C).

The EDGE software’s Base Case is a standardized benchmark that does not adjust to project-specific corporate standards but reflects local norms. The EDGE User Guide states: "The Base Case in EDGE software is automatically generated based on local typical building practices and, where applicable, national building codes for the selected typology and location. It does not incorporate project-specific corporate standards or custom specifications, ensuring a consistent baseline for comparison" (EDGE User Guide, Section 2.3: Using the EDGE App). In this scenario, the hotel developer’s corporate design standards for water fittings, lighting, heating, and air-conditioning are specific to the project, but the EDGE Base Case will still use local typical practices or codes (Option C). Option A is incorrect, as the project can still be certified using the standard Base Case. Option B is wrong because the Base Case does not adapt to corporate specifications. Option D is also incorrect, as the Base Case is not verified on a case-by-case basis for specific hotel chains but is standardized for the region and typology.

Maintaining EDGE Auditor status involves specific requirements to ensure ongoing competence. The EDGE Expert and Auditor Protocols outline these requirements: "To maintain their status, EDGE Auditors must perform at least one project site audit every two years, attend refresher training as required by IFC, and stay updated by studying the EDGE user guides and protocols as they are revised" (EDGE Expert and Auditor Protocols, Section 5.1: Maintaining Auditor Status). Option A (performing at least one project site audit every two years) is explicitly required to demonstrate active engagement. Option B (studying the EDGE user guides as updated) is also necessary to stay current with program changes. Option D (attending refresher training) is mandated to ensure continued education. However, Option C (retaking the auditor exam) is not a requirement for maintaining status: "Once certified, EDGE Auditors are not required to retake the exam to maintain their status, though they may need to retake it if their certification lapses or if significant program changes occur" (EDGE Expert and Auditor Protocols, Section 5.2: Recertification Conditions). Since the question focuses on maintaining status, not recertification after lapse, retaking the exam is not a standard requirement. Thus, retaking the auditor exam (Option C) does not contribute to maintaining Auditor status.

Training for EDGE Experts and Auditors is a structured process managed by specific entities authorized by the IFC. The EDGE Expert and Auditor Protocols specify: "EDGE Faculty are licensed by IFC to deliver training for candidates aspiring to become EDGE Experts and EDGE Auditors. These trainers are selected and trained by IFC to ensure consistency and quality in the delivery of EDGE training programs" (EDGE Expert and Auditor Protocols, Section 3.2: Training Requirements). Option A, EDGE Faculty, directly matches this description. Option B (EDGE Auditors) is incorrect, as auditors perform audits, not training, per the protocols: "EDGE Auditors are responsible for verifying project compliance, not for training others" (EDGE Expert and Auditor Protocols, Section 2.2: Roles). Option C (EDGE Certification Providers) is also incorrect, as their role is to issue certifications, not conduct training: "Certification Providers like GBCI issue EDGE certificates but do not train candidates" (EDGE Certification Protocol, Section 1.3: Certification Process). Option D (Accredited EDGE Experts) is wrong, as Experts advise on projects, not train others, as per the protocols: "EDGE Experts provide consultancy services to project teams" (EDGE Expert and Auditor Protocols, Section 2.1: Roles).

Greywater recovery in EDGE is a water efficiency measure, and the software calculates savings by comparing water consumption before and after implementing the measure. The EDGE Methodology Report explains the calculation method: "Water consumption savings from greywater recovery are calculated as the difference between the Base Case water consumption and the Improved Case water consumption after applying the measure. The Base Case represents the typical water use without any efficiency measures, serving as the benchmark for all savings calculations" (EDGE Methodology Report Version 2.0, Section 4.2: Water Savings Calculations). Option A, Base Case water consumption, is the correct reference point for determining savings, as it establishes the baseline against which the greywater recovery measure is evaluated. Option B (Improved Case water consumption) is the result after applying the measure, not the basis for savings. Option C (cost of water consumption at local tariff) and Option D (incremental cost of installation and cost of water consumption at local tariff) relate to financial outputs, not the direct calculation of water savings, as clarified: "Water savings in EDGE are quantified in volume (liters or cubic meters), not cost, though cost savings are derived later using local tariffs" (EDGE User Guide, Section 5.2: Water Efficiency Measures). Thus, greywater recovery savings are based on Base Case water consumption (Option A).

According to the CBCI EDGE framework, the pathway to becoming an EDGE Auditor is structured to ensure technical competence and familiarity with the EDGE methodology before assuming third-party verification responsibilities. An architect with more than three years of professional experience satisfies the general professional experience requirement; however, this alone is not sufficient to directly become an EDGE Auditor.

The curriculum clarifies that the candidate must first qualify and be recognized as an EDGE Expert. This step ensures that the individual has demonstrated proficiency in using the EDGE software, understands baseline and improved case calculations, and is fully familiar with energy, water, and materials measures within the EDGE Standard. The EDGE Expert credential confirms competence in project modeling and documentation preparation.

Once recognized as an EDGE Expert, the individual can then apply to an accredited EDGE Certification Body or Certifier to become an EDGE Auditor. Auditors operate under Certification Bodies and are responsible for independent design and site audits. They do not apply directly to IFC for this role, nor do they bypass the EDGE Expert stage. Therefore, the correct application process is to first become an EDGE Expert and then apply to a Certifier.

EDGE Zero Carbon certification, like all EDGE certifications, is limited to specific building typologies supported by the EDGE software, as these typologies have predefined usage patterns for accurate modeling. The EDGE User Guide lists the supported typologies: "EDGE certification, including EDGE Zero Carbon, is available for the following building typologies: homes, hotels, offices, hospitals, retail, schools, warehouses, and light industry buildings. Museums are not a supported typology in EDGE, as their unique usage patterns, such as specialized HVAC for artifact preservation, are not modeled in the software" (EDGE User Guide, Section 1.2: Scope of EDGE Certification). Option C, the project cannot be certified because EDGE does not have a ‘museum’ typology, directly aligns with this limitation, as museums are not among the supported building types. Option A (the project team can select any typology they consider applicable) is incorrect, as EDGE requires the use of predefined typologies: "The EDGE software restricts typology selection to predefined categories to ensure accurate Base Case calculations; users cannot create custom typologies for unsupported building types like museums" (EDGE Methodology Report Version 2.0, Section 2.1: Calculation Approach). Option B (operating for at least 6 months at 75% occupancy) and Option D (operating for at least 12 months at 75% occupancy) address operational data requirements for EDGE Zero Carbon, but they are irrelevant if the typology is unsupported: "EDGE Zero Carbon certification requires at least 12 months of operational data at 75% occupancy to verify performance, but this applies only to supported typologies" (EDGE Certification Protocol, Section 2.3: Certification Levels). Since museums are not supported, the operational data requirement does not apply, making both B and D incorrect in this context. The EDGE Certification Protocol further confirms: "Buildings like museums, which are not part of EDGE’s typology list, cannot be certified, as the software cannot generate a Base Case for unsupported building types, ensuring consistency in certification standards" (EDGE Certification Protocol, Section 1.2: Scope of EDGE Standard). The EDGE User Guide adds: "Clients pursuing certification for unsupported typologies, such as museums or cultural centers, will need to explore other green building certifications, as EDGE is not designed for these building types" (EDGE User Guide, Section 1.2: Scope of EDGE Certification). Thus, the project cannot be certified due to the lack of a museum typology (Option C).

The EDGE methodology is designed to calculate resource savings using standardized inputs that reflect the building’s context and design, rather than actual operational data. The EDGE Methodology Report outlines the factors used: "The EDGE methodology is based on climatic conditions of the location, building type and occupant use, and design and specifications. Climatic conditions determine heating and cooling loads, building type and occupant use define usage patterns (e.g., residential vs. hotel), and design and specifications include details like insulation levels, glazing properties, and system efficiencies" (EDGE Methodology Report Version 2.0, Section 2.1: Calculation Approach). Option A (climatic conditions of location), Option B (building type and occupant use), and Option C (design and specifications) are all integral to the methodology. However, Option D (electricity and water bills) is not a factor in EDGE calculations, as the methodology uses predictive modeling, not actual consumption data: "EDGE does not base its calculations on electricity and water bills, as these reflect operational performance rather than design potential. Instead, EDGE uses standardized assumptions about energy and water use based on building type, location, and design inputs" (EDGE User Guide, Section 2.1: EDGE Software Overview). The EDGE Methodology Report further clarifies: "Actual utility bills are not used in EDGE, as the software focuses on predicted savings at the design stage, not post-occupancy performance, except in cases like EDGE Zero Carbon certification where operational data is required" (EDGE Methodology Report Version 2.0, Section 2.2: Data Inputs). Since this question pertains to the general EDGE methodology (not Zero Carbon), electricity and water bills are not a factor. The EDGE User Guide also states: "The methodology relies on theoretical models to estimate resource use, ensuring consistency across projects, rather than variable operational data like utility bills" (EDGE User Guide, Section 2.3: Using the EDGE App). Thus, electricity and water bills (Option D) are not part of the EDGE methodology.

The Coefficient of Performance (COP) is used in EDGE to calculate the electrical power input required for a given thermal output of a chiller. The EDGE Methodology Report defines COP as: "COP is the ratio of thermal output to electrical input, expressed as COP = Thermal Output / Electrical Input. To find the electrical input (power rating), rearrange the formula: Electrical Input = Thermal Output / COP" (EDGE Methodology Report Version 2.0, Section 5.1: Energy Efficiency Metrics). Given the COP of the water-cooled chiller as 6 and the cooling thermal load (thermal output) as 3516 W, the power rating is calculated as follows: Electrical Input = 3516 W / 6 = 586 W. Option A, 586 W, matches this calculation. Option B (3510 W) is incorrect, as it is slightly less than the thermal output, implying an unrealistic COP near 1. Option C (3522 W) is slightly above the thermal output, also incorrect. Option D (21096 W) is the result of multiplying the thermal output by the COP (3516 × 6), which is the inverse of the correct calculation. The EDGE User Guide confirms: "For a chiller with a COP of 6, the electrical input is one-sixth of the thermal output, ensuring energy efficiency is accurately assessed" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). Thus, the power rating is 586 W (Option A).

In EDGE, the Coefficient of Performance (COP) is used to measure the efficiency of heating systems that produce heat using a refrigeration cycle, such as heat pumps. The EDGE Methodology Report specifies: "The Coefficient of Performance (COP) is used in EDGE to evaluate the efficiency of heat pumps, including ground source heat pumps, where it is defined as the ratio of thermal output to electrical input. This metric is not applied to direct heating systems like electric heaters or boilers" (EDGE Methodology Report Version 2.0, Section 5.1: Energy Efficiency Metrics). Option C, ground source heat pump, fits this description as it operates using a refrigeration cycle to transfer heat, and its efficiency is measured by COP in EDGE. Option A (electric heater) has an efficiency typically measured as 100% (or COP of 1), but EDGE does not use COP for such systems, as noted: "Electric heaters are assumed to have a fixed efficiency in EDGE, not evaluated via COP" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). Option B (condensing boiler) uses thermal efficiency (%), not COP, as per: "Boilers in EDGE are assessed by their thermal efficiency, not COP" (EDGE Methodology Report Version 2.0, Section 5.2: Heating Systems). Option D (sensible heat recovery from exhaust air) is a heat recovery method, not a heating system, and does not use COP: "Heat recovery systems are evaluated by their heat recovery effectiveness, not COP" (EDGE User Guide, Section 4.3: Ventilation Measures). Thus, ground source heat pump (Option C) is the correct choice.

Efficiency in fans and pumps is a critical aspect of green building design in EDGE, particularly for reducing energy consumption in HVAC systems. The EDGE User Guide provides detailed guidance on efficiency measures for mechanical systems: "Variable speed drives (VSDs) deliver the highest efficiency in fans and pumps by adjusting the motor speed to match the actual demand, significantly reducing energy consumption compared to fixed-speed systems. VSDs can achieve energy savings of up to 30-50% in HVAC applications by avoiding the constant operation at full speed typical of single or constant speed drives" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). Option D, variable speed drive, aligns with this description as the most efficient option. Option A (two speed drive) offers some efficiency by allowing two operating speeds, but it is less flexible than VSDs: "Two speed drives provide limited efficiency gains, as they cannot continuously adjust to varying loads, unlike variable speed drives" (EDGE Methodology Report Version 2.0, Section 5.1: Energy Efficiency Metrics). Option B (single speed drive) and Option C (constant speed drive) are essentially the same in this context, operating at a fixed speed regardless of demand, leading to energy waste: "Single speed or constant speed drives run at a fixed rate, resulting in higher energy consumption compared to variable speed drives, which modulate speed based on need" (EDGE User Guide, Section 4.2: Energy Efficiency Measures). The EDGE Methodology Report further elaborates: "Variable speed drives are the most efficient option for fans and pumps in EDGE, as they minimize energy use by matching output to demand, unlike two speed or constant speed drives, which operate inefficiently under partial loads" (EDGE Methodology Report Version 2.0, Section 5.1: Energy Efficiency Metrics). This makes variable speed drives (Option D) the clear choice for delivering the highest efficiency in fans and pumps.