(British Thermal Unit): The amount of heat needed
to raise the temperature of one pound of water one degree
Fahrenheit. BTU is used to signify the heating and cooling
capacity of a system and the heat losses and gains of buildings
BTUH: The number of BTUs
produced in one hour.Closed-loop heat pump system:
A heat pump system that uses a loop of buried plastic pipe
as a heat exchanger. Loops can be horizontal or vertical.
Climate Change Action Plan:
A commitment to meet or exceed the targets set by the Kyoto
Protocol. The Protocol is viewed as an opportunity for innovation
and an incentive to develop sources of clean, renewable
energy, which it regards are one of the key advantages in
meeting greenhouse gas emission targets. One might also
take action through a range of clean energy ventures including
new low-impact dams, seven new wind-monitoring sites, geothermal
heating systems and solar energy projects.
COP (Coefficient of Performance):
The ratio of heating or cooling provided by a heat pump
(or other refrigeration machine) to the energy consumed
by the system under designated operating conditions. The
higher the COP, the more efficient the system.
Compressor: The central
part of a heat pump system. The compressor increases the
pressure and temperature of the refrigerant and simultaneously
reduces its volume while causing the refrigerant to move
through the system.
Condenser: A heat exchanger
in which hot, pressurized (gaseous) refrigerant is condensed
by transferring heat to cooler surrounding air, water or
Cycling losses: The actual
efficiency of a heating or cooling system is reduced due
to start-up and shut-down losses. Over-sizing a heating
or cooling system increases cycling losses.
Desuperheater: A device
for recovering superheat from the compressor discharge gas
of a heat pump or central air conditioner for use in heating
or preheating water.
Fossil fuel: Any of several
types of combustible fuels formed from the decomposition
of organic matter. Examples are natural gas, propane, fuel
oil, oil, and coal.
Geothermal heat pump: A
heat pump that uses the earth as a heat source and heat
Heat exchanger: A device
designed to transfer heat between two physically separated
fluids or mediums of different temperatures.
Heat pump: A mechanical
device used for heating and cooling which operates by pumping
heat from a cooler to a warmer location. Heat pumps can
extract heat from air, water, or the earth. They are classified
as either air-source or geothermal units.
Heat sink: The medium--air,
water or earth--which receives heat rejected from a heat
Heat source: The medium--air,
water or earth--from which heat is extracted by a heat pump.
Open-loop heat pump system:
A heat pump system that uses groundwater from a well or
surface water from a lake, pond, or river as a heat source.
The water is returned to the environment.
Payback: A method of calculating
how long it will take to recover the difference in costs
of two different heating and cooling systems by using the
energy and maintenance cost savings from the more efficient
Supplemental heating: A
heating system used during extremely cold weather when additional
heat is needed to moderate indoor temperatures. May be in
the form of fossil fuel or electric resistance.