sugarcane bagasse, fruit pits, and rice hulls). In CHP applications, steam at lower
pressure is extracted from the steam turbine and used directly in a process or for
district heating or is converted to other forms of thermal energy including hot or
chilled water.
Steam turbines offer a wide array of designs and complexity to match desired
applications and performance specifications. Those used for utility services may
have several pressure casings and elaborate design features to maximize power plant
efficiency. For industrial applications, steam turbines are generally of a simpler
single casing design to increase reliability and reduce cost. CHP can be adapted to
both utility and industrial steam turbine designs.
5.3.3 Micro Turbine
Micro turbines are small electricity generators that burn gaseous and liquid fuels to
create high-speed rotation that turns an electrical generator. Current micro turbine
technology is the result of development of small stationary and automotive gas
turbines, auxiliary power equipment, and turbochargers, much of which has been
pursued by the automotive industry since in the 1950s. Micro turbines entered field
testing in around 1997, and commercial service began in 2000.
The size range of micro turbines currently available and in development is from
30 to 400 kW, while conventional gas turbines range from 500 kW to 350 MW.
Micro turbines run at high speeds and, like larger gas turbines, can be used in poweronly generation or in CHP systems. They are able to operate on a variety of fuels,
including natural gas and liquid fuels such as gasoline, kerosene, and diesel fuel or
distillate heating oil. In resource recovery applications, waste gases are burned that
would otherwise be flared or released directly into the atmosphere.
Designed to combine the reliability of auxiliary power systems used onboard
commercial aircraft with the design and manufacturing economies of turbochargers,
units are targeted at CHP and prime power applications in commercial buildings and
light industry. In most configurations, a high-speed turbine (100,000 rpm) drives a
high-speed generator producing direct current (DC) power that is electronically
inverted to 60 (or 50) Hz AC. Micro turbine systems are capable of producing
power at around 25–33% efficiency by employing a recuperate that transfers exhaust
heat back into the incoming air stream. Efficiencies generally decrease at elevated
ambient temperatures. Systems are air-cooled, and some designs use air bearings,
thereby eliminating the water and oil systems used by reciprocating engines. Low
emission combustion systems that provide emissions performance comparable to
larger gas turbines have been developed. The potential for reduced maintenance and
high reliability and durability is currently being demonstrated in actual applications.
Micro turbines are ideally suited for distributed generation due to their flexibility
in connection methods, low emissions, and their ability to provide stable and reliable
power and to be stacked in parallel to serve larger loads. Types of application
include:
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H. Ren et al.
pressure is extracted from the steam turbine and used directly in a process or for
district heating or is converted to other forms of thermal energy including hot or
chilled water.
Steam turbines offer a wide array of designs and complexity to match desired
applications and performance specifications. Those used for utility services may
have several pressure casings and elaborate design features to maximize power plant
efficiency. For industrial applications, steam turbines are generally of a simpler
single casing design to increase reliability and reduce cost. CHP can be adapted to
both utility and industrial steam turbine designs.
5.3.3 Micro Turbine
Micro turbines are small electricity generators that burn gaseous and liquid fuels to
create high-speed rotation that turns an electrical generator. Current micro turbine
technology is the result of development of small stationary and automotive gas
turbines, auxiliary power equipment, and turbochargers, much of which has been
pursued by the automotive industry since in the 1950s. Micro turbines entered field
testing in around 1997, and commercial service began in 2000.
The size range of micro turbines currently available and in development is from
30 to 400 kW, while conventional gas turbines range from 500 kW to 350 MW.
Micro turbines run at high speeds and, like larger gas turbines, can be used in poweronly generation or in CHP systems. They are able to operate on a variety of fuels,
including natural gas and liquid fuels such as gasoline, kerosene, and diesel fuel or
distillate heating oil. In resource recovery applications, waste gases are burned that
would otherwise be flared or released directly into the atmosphere.
Designed to combine the reliability of auxiliary power systems used onboard
commercial aircraft with the design and manufacturing economies of turbochargers,
units are targeted at CHP and prime power applications in commercial buildings and
light industry. In most configurations, a high-speed turbine (100,000 rpm) drives a
high-speed generator producing direct current (DC) power that is electronically
inverted to 60 (or 50) Hz AC. Micro turbine systems are capable of producing
power at around 25–33% efficiency by employing a recuperate that transfers exhaust
heat back into the incoming air stream. Efficiencies generally decrease at elevated
ambient temperatures. Systems are air-cooled, and some designs use air bearings,
thereby eliminating the water and oil systems used by reciprocating engines. Low
emission combustion systems that provide emissions performance comparable to
larger gas turbines have been developed. The potential for reduced maintenance and
high reliability and durability is currently being demonstrated in actual applications.
Micro turbines are ideally suited for distributed generation due to their flexibility
in connection methods, low emissions, and their ability to provide stable and reliable
power and to be stacked in parallel to serve larger loads. Types of application
include:
114
H. Ren et al.