6.2 Flashcards
- Also known as ______ heat and power (CHP)
- Is The use of a heat engine (or other means) to
simultaneously generate both electricity and heat.
COGENERATION SYSTEM, combined
Its principal purpose is to produce electricity but,
as a _________, the heat produced is used for
_________, _______, or ___________
heating
COGENERATION SYSTEM, by-product, heating water, space heating, industrial process
COGENERATION SYSTEM is most efficient when the heat can be used ______
or very close to it because overall efficiency is ______ when the heat must be transported
through costly insulated pipes
onsite, reduced
__________ _____ are generally classified by the type of_______ (i.e. drive system), generator, and ______.
Cogeneration units, prime mover, fuel used
Basic elements of a conventional cogeneration
system
1.Prime Mover (Engine) – use to drive generators
2.Generator – generate electricity (power)
3.Heat recovery system
4.Exhaust system
5.Controls
6.Acoustic enclosure
COGENERATION SYSTEM uses many engine technologies, including:
- Internal combustion reciprocating engine base
cogeneration systems - Reciprocation external combustion Stirling engine base
cogeneration systems - Fuel based cogeneration systems
- Microturbine based cogeneration systems
- Are most common and Efficient
prime mover used commercial
cogeneration systems - Are based on the _________
or the compression ignition.
Internal combustion
Reciprocating Engine, spark ignition
- involves only the ________ of air in the cylinder; the
fuel is introduced into the cylinder towards the end of
the compression stroke. - The spontaneous ____________ is thus caused by the high
temperature of the compressed mixture. - run on diesel fuel or heavy oil; as a result, they are
primarily used for _________________.
Compression-ignition (Diesel) Engine, compression, ignition, large-scale cogeneration
- The mixture of air and fuel is compressed in each
cylinder before ignition is caused by an ___________. - These engines are mainly ________ direct-injection
engines fitted with a _______ and ________. - They run on gasoline, natural gas, or liquid propane gas
(LPG).
Spark Ignition (Otto cycle) Engine, externally
supplied spark, four-stroke, turbocharger, intercooler
- the engine drives a generator to produce electricity.
- __________is captured through heat recovery
from the exhaust gas, engine oil, and cooling water,
which can then be used for space or water - This typical engine efficiencies are between ____ and
_____.
Internal combustion Reciprocating Engine, Thermal energy, 20, 30%
By recovering heat from the cooling systems and exhaust, approximately ____ to ____ of the energy derived from the fuel is utilized to produce both _______ and __________.
75, 90%, electricity, useful heat
- is a closed-cycle, piston-driven, external heat engine with a gaseous working fluid that under cooling, compression, heating, and expansion drives a _______.
- No _______ are required, unlike other types of piston engines.
Reciprocation external combustion Stirling
engine, piston, valves
- It is high efficiency, quiet operation, and ease with
which it can use waste heat. - is currently being researched as a ________
(engine) in residential cogeneration systems.
Reciprocation external combustion Stirling
engine, prime driver
In Reciprocation external combustion Stirling engine the working fluid is temporarily sealed within the
engine’s system so that no gas enters or leaves the
engine. T or F
F (permanently)
_________ is accomplished by moving the gas
back and forth between hot and cold heat exchangers, often with a _______ between the heater and cooler.
Piston movement, regenerator
