absorption chiller |
water chiller based on absorption of refrigerant vapor
into a liquid solution, pumping of the solution to elevated
pressure, and the release (desorption) of refrigerant
vapor through addition of heat; absorption chillers require
less energy because the pumping process involves a liquid;
direct-fired chillers employ natural gas burners, indirect-fired
chillers use steam or hot water from a separate process
(such as the hot exhaust gases from electric generation);
single-, double-, and triple-effect chillers employ multiple
stages of desorption and internal use of waste heat to
boost efficiency
|
| demand
charge |
charges
for the use of electricity based on the maximum power
requirement, electrical demand, during a specified period
of time, typically a month ($/kW)
|
| desiccant |
a
solid or liquid material with an affinity for absorbing
water molecules
|
| engine-generator |
electrical
generator using a reciprocating, Sterling, or rotary engine
|
| enthalpy
wheel |
heat
exchanger rotating through building supply and exhaust
air flows to transfer energy from one air stream to the
other
|
| evaporative
cooling |
lowering
the temperature of air through the evaporation from a
water or wetted membrane; direct evaporative cooling adds
water to the supply air while indirect evaporative cooling
adds water to the exhaust air and incorporates a heat
pipe or thermal wheel for indirect cooling of the supply
air
|
| fuel
cell |
device
for producing electricity using a chemical process rather
than conventional combustion processes with electric generators
|
| heat
wheel |
heat
exchanger rotating through building supply and exhaust
air flows to transfer heat from one air stream to another
|
| latent
cooling load |
amount
of cooling required to reduce humidity of air in conditioned
space to specified level for comfort
|
| microturbine
power generator |
turbine-engine
driven electrical generator with output power under 100
kW
|
| real
time pricing |
charges
for electrical demand and consumption based on instantaneous
cost of production and distribution as opposed to fixed
rates or fixed time-of-day rates
|
| sensible
cooling load |
amount
of cooling required to reduce the temperature of air in
the conditioned space to a specified level for comfort
|
| thermal
wheel |
heat
exchanger rotating between two air flows to transfer heat
from one to the other
|
| ton
or refrigeration ton |
quantity
of cooling available from melting 2000 pounds of ice;
12,000 Btu/h or 3.1413 kW
|
| vapor
compression air conditioning |
cooling
system based on compression of a gaseous refrigerant to
a high pressure, and heat transfer with changes of state
(i.e. liquid and vapor) to produce useful heating or cooling
|
| waste
heat |
portion
of the energy input to a mechanical process which is
rejected to the environment
|
