Glossary

The terms, acronyms and technical words we use on this site, explained in a few words.

Heating, cooling and ventilation

HVAC Heating, Ventilation and Air Conditioning (AVAC in Portuguese): The systems that heat, cool and renew the air in a building. In non-residential buildings it is often the largest share of the energy used.
AHU Air Handling Unit (UTA in Portuguese): The unit that filters the air, heats or cools it, and sends it around the building through ducts. It can mix fresh air with the air returning from the rooms.
FAHU Fresh Air Handling Unit (UTAN in Portuguese): An AHU that works with fresh outdoor air only. It provides the air renewal and indoor air quality, while other equipment usually heats and cools the rooms.
VE, VI and VP Extract, supply and pressurisation fans: The fans in an installation, named after what they do: the VE removes stale air (toilets, kitchens), the VI brings in fresh air and the VP keeps a space at higher pressure — a stairwell, for example, so that smoke cannot get in during a fire.
FCU Fan Coil Unit (VC or FC in Portuguese): A unit with a fan and a coil carrying hot or chilled water, which heats or cools the air in a room. It is often the unit in the ceiling or under the window of a hotel room.
Chiller UPAG in Portuguese: The machine that produces the chilled water that flows through the fan coils and AHUs to cool the building. Many can also produce hot water, working as a heat pump.

Split: The most common type of air conditioning: an indoor unit in the room and an outdoor unit, connected by pipes carrying the refrigerant. Each indoor unit serves one room.
IU and OU Indoor and outdoor units (UI and UE in Portuguese): The two halves of an air conditioning system: the indoor unit, in the room, blows the air; the outdoor unit, outside the building, releases or absorbs the heat. On Portuguese drawings they appear as UI and UE.
VRF / VRV Variable Refrigerant Flow / Variable Refrigerant Volume: An air conditioning system in which a single outdoor unit serves many indoor units, adjusting the amount of refrigerant sent to each. VRV is the name used by Daikin, which invented it; VRF is the general term.
COP Coefficient of Performance: How much heat a unit delivers for each unit of electricity it uses when heating. A heat pump with a COP of 4 gives 4 kWh of heat for every kWh it uses. SCOP is the same ratio over a whole season.
EER Energy Efficiency Ratio: The same as the COP, but for cooling: how much cooling a unit produces for each unit of electricity it uses. SEER is the seasonal version.
Enthalpy: The energy contained in the air, adding the heat of its temperature to the heat held in its moisture. It tells you what it costs to treat the air; an enthalpy recovery unit reclaims both from the air leaving the building.
IAQ Indoor Air Quality (QAI in Portuguese): How clean and healthy the air inside a building is: CO₂, particles, humidity, volatile compounds. In non-residential buildings it is regulated by law, and the ventilation systems must keep it within limits.

Hot water and renewables

DHW Domestic Hot Water (AQS in Portuguese): The hot water from taps and showers. In a hotel it is often the second-largest energy use, after heating and cooling.
Heat pump BC in Portuguese: A machine that takes heat from the air, water or ground and moves it to where it is needed — to heat the building or the water. For each unit of electricity it uses, it delivers several units of heat (see COP).
High-temperature heat pump BCAT in Portuguese: A heat pump that heats water to higher temperatures, around 65 °C or more. It can replace a boiler for a hotel’s hot water, often without changing the rest of the installation.
Solar thermal panel: A panel that uses the sun to heat water, rather than to produce electricity like a PV panel. It is used mainly for domestic hot water.
PV Photovoltaic (FV in Portuguese): Panels that turn sunlight into electricity. On a building’s roof they are mainly used for self-consumption: the electricity is used on site, and any surplus can go to the grid.

Building automation and control

BMS Building Management System (GTC in Portuguese): The system that controls and monitors a building’s equipment from a single place: heating and cooling, ventilation, lighting, hot water, alarms. It switches things on and off, adjusts them and raises an alarm when something goes wrong.

BACS Building Automation and Control System (SACE in Portuguese): The term the law uses for a building’s automation and control systems — in practice, the BMS. The European directive on the energy performance of buildings requires them in non-residential buildings with larger heating and cooling systems.
DDC Direct Digital Control: The digital controllers that, in a BMS, receive the signals from the sensors and control each piece of equipment. They are the local “brain” of each plant room or panel.
EMS Energy Management System: The platform that measures and analyses the energy use of one or more buildings: where it is used, when, and what it costs. It shows deviations and where savings can be made.
IoT Internet of Things: Sensors and devices connected to the internet that send data and receive commands without anyone having to be there. They make it possible to follow a building room by room — temperature, occupancy, energy use — remotely.

Maintenance and building management

FM Facility Management: The management of everything that keeps a building running day to day — maintenance, energy, cleaning, security, space — so that the people using it do not have to think about it.
PMP Preventive Maintenance Plan: The list of maintenance tasks for each piece of equipment and how often they are carried out, to prevent breakdowns rather than repair them. Regulations require one in many non-residential buildings.
CMMS Computerised Maintenance Management System: The software that organises maintenance: the equipment, the plans, the work orders and the history of each item. Âmago’s GEMAX is one of these systems.

BIM Building Information Modelling: A digital model of the building in which every element — walls, pipes, equipment — carries its own information. It serves the design, the works and then the maintenance, and can be built from a 3D survey of what already exists.

Energy performance contracts

EPC Energy Performance Contract: An agreement to improve a building’s energy efficiency, reduce costs and lower CO₂ emissions, with contractually guaranteed savings. It includes the implementation of energy efficiency measures and the monitoring of results throughout the contract. The investment is recovered through the savings achieved, and the service provider’s payment is linked to the performance delivered.
ESCO Energy Service Company (ESE in Portuguese): A company that improves the energy efficiency of its clients’ buildings and takes on the risk of the result, usually through energy performance contracts. Âmago is an ESCO.
M&V Measurement and Verification: The process that proves how much was actually saved: it compares energy use after the measures with what the building would have used without them, adjusted for weather and occupancy. It is the basis for payment under an EPC.
IPMVP International Performance Measurement and Verification Protocol: The international protocol that sets out how savings are measured and verified, so that results are comparable and credible. It is the reference for energy performance contracts.
CMVP Certified Measurement and Verification Professional: The certification for professionals qualified to measure and verify savings under the IPMVP, awarded by the Association of Energy Engineers (AEE) with EVO.

Certification and regulations

SCE Energy Certification System for Buildings (Portugal): The national system that sets out how the energy performance of buildings is assessed and certified, and which rules they must meet — for homes and for commercial and service buildings. The energy certificate and the qualified experts are part of it.
Energy Performance Certificate CE in Portuguese: The document that rates the energy efficiency of a building or a unit on a scale from A+ to F, and recommends improvements. It is required to sell or let. There is the certificate for an existing building or unit, and the first one (1.º CE), issued after construction works.
PQ Qualified Expert (Perito Qualificado): The professional authorised to issue energy certificates in Portugal. A PQ I certifies homes and small non-residential buildings; a PQ II certifies large non-residential buildings.
GES Large commercial and service buildings (Portuguese regulations): In Portuguese regulations, the larger commercial and service buildings. They have their own rules for energy certification, maintenance and indoor air quality.
SGCIE Intensive Energy Consumption Management System (Portugal): The scheme for installations that use large amounts of energy: it requires regular energy audits and a plan to reduce consumption.

Electricity

E-REDES: The operator of the electricity distribution network in mainland Portugal. It connects installations to the grid and manages the meters — and holds the consumption records for every quarter of an hour.

BTN and BTE Normal and special low voltage (Portuguese supply levels): The two low-voltage supply levels in Portuguese electricity contracts. BTN is for homes and small buildings, up to 41.4 kVA of contracted power; BTE is for higher power, with a more detailed bill — peak hours, reactive energy. Larger buildings are connected at medium voltage (MT).
MV Medium Voltage (MT in Portuguese): The grid connection level between 1 kV and 45 kV, used by large buildings — hotels, hospitals, shopping centres. The building has its own transformer substation, which steps the voltage down to the level used inside, and the bill is like the BTE one: four time-of-use periods, peak-hour power and reactive energy.
Peak, mid-peak, off-peak and super off-peak hours The time-of-use periods on Portuguese electricity bills: The periods into which the day is divided on the electricity bill, each with its own price: peak is the most expensive, when the grid is most loaded; super off-peak, in the early hours, the cheapest. The tariff sets how many periods apply — single-rate, two-, three- or, for BTE and medium-voltage supplies, four-rate.
Contracted power: The maximum power the installation can draw from the grid at once, paid for every day on the bill whether it is used or not. On BTN supplies it is chosen in the contract; on BTE and medium-voltage supplies it is, as a rule, the highest power the meter has recorded over the last twelve months.
Peak-hour power: The average power the installation draws during peak hours, charged separately on BTE and medium-voltage supplies. It is one of the heaviest items on the bill, and one that falls the most when consumption is moved out of peak hours — heating and cooling, hot water, vehicle charging.

Active and reactive energy: Active energy is the energy that does useful work — heating, lighting, driving motors — and is what you pay for in kWh. Reactive energy flows back and forth between the grid and equipment such as motors and transformers without doing work; on BTE and medium-voltage supplies, above a certain limit, it is charged as a penalty, and it is corrected with capacitor banks. Together they make up the apparent energy, which the installation has to carry.
CIEG General economic interest costs (Portugal): The part of the electricity bill that pays not for the energy but for public policies: support for renewables and tariff convergence for the autonomous regions, among others. They are set every year and add to the final price.

Funding

Portugal 2030: The programme that distributes the 2021–2027 European funds in Portugal, including support for energy efficiency in companies and buildings. Âmago prepares applications for these funds.

Public bodies

DGEG Directorate-General for Energy and Geology: The government body that sets and monitors energy policy in Portugal. It is, for example, where self-consumption generation installations are registered.
ADENE Portuguese Energy Agency: The Portuguese energy agency. It manages the energy certification system for buildings (the SCE) — every certificate is registered there — and promotes energy efficiency.
APA Portuguese Environment Agency: The government body responsible for the environment. In heating and cooling, it is the authority for fluorinated gases — the greenhouse refrigerant gases used in air conditioning equipment.