§ Glossary
Every term, defined — no assumed knowledge.
The audit world runs on acronyms. Here is the language SEU uses — from SEU and EnPI to pinch, IAPWS-IF97 and ESRS E1 — in plain English, grouped by theme.
§ 01
ISO 50001 & measurement
The energy-management vocabulary the whole engine is organised around.
- Significant Energy UserSEU
- An end-use, system or facility that accounts for a large share of energy consumption or offers substantial savings potential. ISO 50001 §6.3 makes identifying SEUs the backbone of the energy review — SEU the product is named for them.
- Energy Performance IndicatorEnPI
- A metric that quantifies energy performance — e.g. kWh per litre of WFI, or kWh per kg of product — so improvement can be tracked over time against a baseline.
- Energy BaselineEnB
- The reference energy performance over a defined period, against which future consumption and savings are measured.
- Specific Energy ConsumptionSEC
- Energy used per unit of output or activity — the normalised number that lets you compare a plant to itself across changing production.
- Measurement & VerificationIPMVP
- The International Performance Measurement and Verification Protocol — the method for proving savings are real by comparing measured energy against an adjusted baseline. SEU calibrates the model to meter data in this spirit (Option C, whole-facility).
§ 02
Analytics
How the 8,760-hour picture turns into decisions.
- Load Duration CurveLDC
- The year’s hourly demand sorted high-to-low. It reveals how much of the bill is base-load versus peak, and where load-shifting or right-sizing pays.
- Pinch analysis
- A thermodynamic method that finds the minimum hot and cold utility a process needs by matching heat sources to sinks. It exposes where heat recovery is physically possible before any equipment is specified.
- Marginal Abatement Cost CurveMACC
- A chart ranking carbon-saving measures by cost per tonne of CO₂ avoided, so the cheapest abatement is done first and the decarbonisation budget goes furthest.
- Coefficient of PerformanceCOP
- Cooling (or heating) delivered per unit of electricity drawn by a chiller or heat pump. Higher is better; it falls as the temperature lift grows, which is why a −40 °C process chiller can never reach a comfort chiller’s COP.
- Free cooling
- Rejecting heat to cool ambient air instead of running compressors — viable for many hours a year in a cool maritime climate like Ireland’s. SEU counts the real free-cooling hours from the weather, not a guess.
§ 03
Physics & standards
The published references every number rests on — not placeholder curves.
- IAPWS-IF97
- The international standard formulation for the thermodynamic properties of water and steam. It gives the steam tables behind every boiler, header and condensate calculation.
- ASME PTC 4
- The performance test code for fired steam generators — the basis for the boiler efficiency (heat-loss method) the engine computes.
- AHRI 550/590
- The North American standard for rating water-chilling packages, including IPLV — the integrated part-load value SEU uses for realistic chiller energy across the year, not just at full load.
- ASHRAE psychrometrics
- The moist-air property relationships (enthalpy, humidity ratio, dew point) behind every air-handling-unit cooling, heating, dehumidification and humidification load.
- ISO 14644
- The cleanroom classification standard. It sets the air-change rates and filtration that make pharmaceutical HVAC so energy-intensive.
§ 04
Pharma utilities
The systems that make a GMP plant unlike any commercial building.
- Water for InjectionWFI
- Ultra-pure water for parenteral manufacture, produced by multi-effect distillation or vapour compression and held in a hot recirculating loop — a continuous, energy-hungry utility.
- Pure steam
- Pyrogen-free steam generated from purified water for sterilisation (SIP) and humidification of classified spaces, distinct from plant (utility) steam.
- CIP / SIP
- Clean-in-place and steam-in-place — the automated cleaning and sterilisation cycles that drive batch peaks in steam, water and effluent.
- Lyophiliser
- A freeze-dryer. Its cascade refrigeration reaches −40 °C and below to freeze product under vacuum, one of the most power-dense loads on site.
- Air Handling UnitAHU
- The unit that conditions and delivers air to a space. In a cleanroom it runs high air-change rates with tight temperature and humidity control, often on 100% fresh air.
- EU GMP Annex 1
- The European good-manufacturing-practice rules for sterile medicinal products — the constraints that shape cleanroom design, pressure cascades and HVAC.
- 21 CFR Part 11
- The US FDA rule on electronic records and signatures — the data-integrity and audit-trail mindset SEU carries through the model and report.
§ 05
Finance & climate disclosure
Turning energy into a number the board and the regulator recognise.
- Net Present ValueNPV
- The value today of a measure’s future cash flows, discounted for time. SEU ranks opportunities on NPV — not simple payback — with time-of-use carbon and a confidence band.
- Scope 1 / 2 / 3
- The GHG Protocol emission categories: direct combustion (1), purchased electricity (2) and value-chain (3). A plant’s gas boilers are Scope 1; its grid power is Scope 2.
- Carbon intensity
- Grid emissions per unit of electricity, in gCO₂ per kWh. Multiplying annual electricity by this gives Scope 2 emissions; it varies by country and, increasingly, by the hour.
- TCFD
- The Task Force on Climate-related Financial Disclosures — the framework for reporting climate risk and transition plans, which the report’s climate section maps to.
- CSRD / ESRS E1
- The EU Corporate Sustainability Reporting Directive and its climate-change standard (ESRS E1), mandatory for large companies and the reason energy is now a board-level line.
See the terms at work.
Open a sample audit and watch SEUs, EnPIs and a MACC come out of a real model — or read how the numbers are made.