Micro gas turbine as combined heat and power plant
- thermal utilization of exhaust gas heat with low pressure loss on the exhaust gas side
- integration into modern heating systems
- optimization of the annual utilization rate
- Adaptation to the electricity tariff structure (reduction of peak power, avoidance of operation in off-peak tariff periods)
Warm/hot water production
Microturbines are ideally suited for controlled, decentralized energy supply due to their small power units and excellent operating characteristics (nearly constant efficiency over a wide load spectrum). By using the microturbine in cogeneration, overall efficiencies of up to 86% can be achieved in standard heating systems with temperatures of 60/80°C. Higher efficiencies are possible by optimizing the heat exchanger to the application. For example, we offer a heat exchanger with a thermal capacity of 75kW, achieving an exhaust gas temperature of 65°C. Another possibility results from lowering the operating temperatures or the flow rates, if the heat transfer medium temperature is lowered. Since the microturbine is operated with a lambda of 6-9, the exhaust gas dew point is also very low, so that theoretically exhaust gas temperatures of about 40°C after the heat exchanger are possible without any problems.
The microturbine-specific exhaust gas characteristic with constantly occurring heat at a high temperature level (approx. 300°C) in only one exhaust gas stream is a decisive advantage in direct exhaust gas utilization compared to cogeneration plants based on piston engines. The use of oil-free microturbine exhaust gas with oxygen contents of 17 to 18% by volume and very low pollutant concentrations is unproblematic.
The use of microturbines for drying is already being applied in many different industries. These include the stone and earth industry, paper/cardboard industry, animal feed industry,...
Another field of application is steam generation, which can be realized by the high exhaust gas temperature of microturbines with exhaust gas heat exchangers.
In the field of steam generation by means of microturbines we cooperate with partners such as Saacke, Hagelschuer, VKK standardkessel köthen GmbH, Aprovis, ALFA LAVAL and also with the company SKS for efficient burner solutions (www.sks-systems.com).
Example of Applications
Examples of applications in industry include food manufacturers, pet food producers, large-scale laundries, breweries and chemical manufacturers.
The advantage of the high exhaust gas temperature is also evident when coupling with an absorption refrigeration system: hot water temperatures of 80-90°C are required for this. The advantage of coupling an absorption chiller is the increase of the annual operating hours of the CHP unit. Thus, the microturbine can be operated in summer as well as in winter with high utilization rates. Such a plant is thus suitable for the base load supply of buildings with a constant demand for electricity, heating and cooling.
The microturbine thus offers the possibility of ensuring the total energy supply of a building by simply coupling an absorption chiller. Such an installation achieves efficiencies of up to 85% and is particularly suitable in:
- commercial high-rise buildings
- larger supermarkets
- event halls
- commercial units
Cogeneration is based on the simultaneous generation of mechanical energy, which is usually converted directly into electricity, and heat, which can be used directly for refrigeration using sorption technology.
Absorption refrigeration systems are based on a technology introduced by Albert Einstein in 1926. It uses a refrigeration cycle in which the changes of state of the refrigerant water and the absorber lithium bromide reach the temperature parameters of conventional chillers.
Century absorption chillers
Century absorption chillers are LiBr units capable of producing refrigeration down to 6°C and are well suited for use in conjunction with microturbines.
Whether used individually or in conjunction with a Capstone microturbine, Century absorption chillers feature:
- a tremendous service life of 30 years,
- tremendous efficiency - 2,000kW cooling with less than 10kW electric,
- easy handling
- few and easily accessible wearing parts - the units are therefore very low maintenance
- 100% ozone friendly, CFC free
- low noise and low vibration
Hot water driven, steam driven or gas fired - the units are available in power ranges from 35 kW to 5,275 kW and you can choose between a standard product or an individually designed unit.
Micro gas turbine for regenerative gases
The Capstone microturbines can be operated with:
- Natural gas
- Liquefied petroleum gas
- Natural gas blends with up to 30% hydrogen content
- special gases such as associated petroleum gas
Due to its simple design, the turbine is also particularly suitable for use with regenerative gases, such as
- landfill gas
- sewage gas
In the combustion of biogas, the content of hydrogen sulfide (H2S) is a decisive factor for the service life of the engines or their maintenance requirements. The methane in the biogas reacts in the engine to form water vapor, among other things. This in turn combines with H2S from the biogas to form sulfuric acid (H2SO4). The sulfuric acid is absorbed by the oil film of the cylinder walls and enters the oil circuit. As the bearings are lubricated with this oil, the H2SO4 reaches the bearing surfaces, which wear more quickly due to this chemical load.
Due to their compact design (with integration of compressor, turbine, combustion chamber, recuperator and generator), microturbines are ideally suited for use with lean gases. The only moving component is the high-speed rotor, which integrates the compressor and turbine runner as well as the generator rotor. Furthermore, no lubricant is required in the Capstone turbine because the rotor is air-bearing. This avoids the corrosion problems associated with internal combustion engines caused by H2S components in the biogas. The manufacturer Capstone states that up to 7 vol-% H2S can be tolerated by the MicroTurbine. In this way, stresses are reduced to a minimum and the service life of the machine is increased. Thus, a turbine achieves a service life of approximately 80,000h compared to 50,000h for engines. When used with biogas, the service life of motors is even assumed to be 40,000h.
Does the microturbine CHP solution fit our project?
Let's find out! Sent your request to firstname.lastname@example.org!
We will immediately check the general conditions for an economical use of the microturbine at your site.