Below are some terms you may encounter while researching energy related products, heating and efficiency:
AFUE (annual fuel utilization efficiency): an efficiency rating that measures the efficiency with which gas and other fossil-fuel-burning appliance use their primary fuel source over an entire heating season. It does not take into account the efficiency with which any component of the system, such as a furnace fan motor, uses electricity. AFUE is expressed as a percentage that indicates the average number of Btu worth of heating comfort provided by each Btu worth of fuel consumed by the system. For instance, a gas furnace with an AFUE of 80% would provide 0.8 Btu of heat for every Btu of natural gas it burned.
Air infiltration: the introduction, usually unintentional, of unconditioned outdoor air into a mechanically heated and/or cooled building. Air infiltration can occur through any opening in the home’s structure, including seams where walls meet other walls, window or door frames, or chimneys; holes where wires or pipes penetrate walls, floors or ceilings/roofs; and between the loose-fitting meeting rails of double-hung windows or a door bottom and door threshold. It is one of the major causes of unwanted heat gain and loss, and personal discomfort in buildings.
Alternating Current (AC) – An electric current that reverses its direction at regular intervals or cycles; In the U.S. the standard is 120 reversals or 60 cycles per second; typically abbreviated as AC
Amp – short for “ampere” – this measures the amount of electricity moving through a wire. Most household appliances use 15 or 20 amps of power. Amps are what give electricity its “shock.”
Biomass Fuel: Any organic (plant or animal) material which is available on a renewable basis, including agricultural crops and agricultural wastes and residues, wood and wood wastes and residues, animal wastes, municipal wastes, and aquatic plants
BTU (British thermal unit): a measurement of the energy in heat. It takes one Btu of heat to warm one pound of water by 1° Fahrenheit. Btu can be used either to define an air conditioner’s cooling capacity (i.e., the number of Btu of heat that can be removed by the system) or a furnace’s heating capacity (i.e., the number of Btu of heat that can be supplied by the system).
Chemical Energy – Energy stored in a substance and released during a chemical reaction such as burning wood, coal, or oil.
Combustion – Chemical oxidation accompanied by the generation of light and heat.
Conduction is the transfer of heat through solid objects such as glass, dry wall, brick and other building materials. The greater the difference between the outdoor and indoor temperatures, the faster conduction can occur, increasing a building’s energy gain or loss.
Convection is the transfer of heat to or from a solid surface via a gas or liquid current. Where home heat loss and gain are concerned, heat convection is caused by air (gas) currents that carry heat from your body, furniture, interior walls and other warm objects to windows, floors, ceilings, exterior walls and other cool surfaces.
Conversion- A number that translates units of one measurement system into corresponding values of another measurement system.
Cord of Firewood: a tightly stacked pile of wood logs measuring 4′ x 4′ x 8′ (128 cubic feet).
Daylighting is the technique of using natural light from windows, skylights and other openings to supplement or replace a building’s artificial lighting system. When applied properly, daylighting can reduce lighting costs. When applied improperly, however, it can not only lead to inappropriate light levels but can also raise the building’s cooling costs by introducing high levels of solar heat into the interior of the building. Also see SOLAR GAIN to see how sunlight can affect heating costs.
Direct Current – An electric current that flows in only one direction through a circuit, as from a battery.
Efficiency is the degree to which a certain action or level of work can be effectively produced for the least expenditure of effort or fuel. BTU of energy consumed (input) x efficiency = BTU output.
Energy: The ability to do work or the ability to move an object. Electrical energy is usually measured in
kilowatthours (kWh), while heat energy is usually measured in British thermal units (Btu).
Energy Efficiency – Refers to activities that are aimed at reducing the energy used by substituting technically more advanced equipment, typically without affecting the services provided. Examples include high-efficiency appliances, efficient lighting programs, high-efficiency heating, ventilating and air conditioning (HVAC) systems or control modifications, efficient building design, advanced electric motor drives, and heat recovery systems. asurion customer service