Cogeneration
What is a cogeneration plant
Cogeneration is the simultaneous production of electricity and heat coming from a single energy source, realized in a sole integrated system, thanks to the combination of tested and reliable technology.
Any plant that generates electric power also produces waste heat, which this technology exploits through endothermic engines, that can supply from a few KW to a few dozen MW, and return dispersible heat to adapted temperatures for industrial and civil use.
Technical progress has placed interesting heat recovery systems beside these machines, extending the potential of cogeneration enormously.
The combined production can increase the use efficiency of fossil fuels up to and over 80%; to which correspond lesser costs and lesser emissions of pollutants and green house gases compared to the separate production of electricity and heat.
Compared to power plants, cogeneration has natural distribution and is carried out by small plants that are able to generate heat and electricity for large structures or small town centres. The combustion in the small cogeneration plants saves up to 40% in using primary energy sources.
Cogeneration is the simultaneous production of electricity and heat coming from a single energy source, realized in a sole integrated system, thanks to the combination of tested and reliable technology.
Any plant that generates electric power also produces waste heat, which this technology exploits through endothermic engines, that can supply from a few KW to a few dozen MW, and return dispersible heat to adapted temperatures for industrial and civil use.
Technical progress has placed interesting heat recovery systems beside these machines, extending the potential of cogeneration enormously.
The combined production can increase the use efficiency of fossil fuels up to and over 80%; to which correspond lesser costs and lesser emissions of pollutants and green house gases compared to the separate production of electricity and heat.
Compared to power plants, cogeneration has natural distribution and is carried out by small plants that are able to generate heat and electricity for large structures or small town centres. The combustion in the small cogeneration plants saves up to 40% in using primary energy sources.
Who is it for
Cogeneration is particularly indicated for all the realities that need a normal amount of hot water for heating in the winter but also a large amount in the summer season.
In the case that cooling is requested, we speak about tri-generation (electric energy plus hot and cold thermal energy).
The main receivers need at least 3500 hours of heat per year.
Cogeneration is particularly indicated for all the realities that need a normal amount of hot water for heating in the winter but also a large amount in the summer season.
In the case that cooling is requested, we speak about tri-generation (electric energy plus hot and cold thermal energy).
The main receivers need at least 3500 hours of heat per year.
- Air-conditioning of buildings for living or industrial use: hospitals, clinics, rest homes, hotels, fitness centres, swimming pools, shopping centres, blocks of flats, offices, warehouses.
- Heat use for industrial manufacturing: galvanic industries, tanneries, food industries, pharmaceutical industries, exsiccation processes, pasteurization processes, green houses.
- Biogas use by renewable sources: waste dumps, purifiers, refluent water, pig and cattle farms, biomasses of agricultural and not food origin.
Plant components
Thanks to these characteristics, they are undisputed leaders of applications with up to 5000 KW of electric power.
- Main engine: any engine used for converting fuel into mechanical energy
- Generator: converts mechanical energy produced by the engine into electrical energy.
- Thermal recovery system: collects and converts the energy contained in the waste of the main engine into usable thermal energy.
- Electric inter-connections.
Thanks to these characteristics, they are undisputed leaders of applications with up to 5000 KW of electric power.
Types of cogeneration plants
The most common cogeneration plant is the one with endothermic engine.
Tri-generation allows electricity, heat and chilling to be obtained simultaneously.
The transformation of thermal energy into cooling energy is made possible by using a cogenerator combined with an absorption chiller group in which its function is based on transforming the state of the cooling fluid (water) in combination with the substance used to absorb.
In a tri-generation system the global production increases because a higher percentage of calorific power of fuel is used. In fact more than 4/5 of energy is used, since the heat is directly recovered (cogeneration function) or as a source for the refrigerated cycle (tri-generation function).
The most common cogeneration plant is the one with endothermic engine.
Tri-generation allows electricity, heat and chilling to be obtained simultaneously.
The transformation of thermal energy into cooling energy is made possible by using a cogenerator combined with an absorption chiller group in which its function is based on transforming the state of the cooling fluid (water) in combination with the substance used to absorb.
In a tri-generation system the global production increases because a higher percentage of calorific power of fuel is used. In fact more than 4/5 of energy is used, since the heat is directly recovered (cogeneration function) or as a source for the refrigerated cycle (tri-generation function).
Feed and fuels
Besides the traditional fossil fuels and methane, a cogeneration plant can be fed by technologies that use renewable energy sources (photovoltaic, hydroelectric, aeolian), renewable fuels (biogas from biomass and vegetable oils, such as colza, sunflower and palm oil) or alternative fuels (biogas from waste).
Biogas
All installed cogenerators from E++ can be fed from biogas from waste, biogas from civil and industrial purification, biogas from anaerobic digestion of livestock sewage.
Since the chemical properties of biogas are particularly aggressive for the mechanical components of the cogenerator, purification is firstly carried out through dehumidification systems by refrigerators and with de-pulverizing apparatus to get rid of hydrogen sulphide in the case of biogas from purification.
Vegetable oil
If fed by this fuel, the Electrical Services Operator qualifies cogenerators as Plants Fed by Renewable Sources and so they qualify for the Green Certificate incentive.
A condition not to be set aside for having acknowledged this incentive however, is that vegetable oil does not have any chemical treatment of esterification: the only processing that can sustain oil is the squeezing out and filtration of various types of seeds (sunflower, colza, palm for example).
The particular chemical composition and physics of vegetable oil ensures that the engines that are used are modified to guarantee maximum cogeneration performance, guaranteed by E++.
Biomass from animal sewage
Livestock refluent which is mainly liquid has a percentage of dry substances that varies from 2 to 5% and a high content of COD (Carbon present), that favours the production of methane. It is collected by a pipe that starts from the barn and goes towards a tank that is sufficiently large for the yearly refluent collection. It is withdrawn from the tank and converged to the engine to produce electric and thermal energy.
Besides the traditional fossil fuels and methane, a cogeneration plant can be fed by technologies that use renewable energy sources (photovoltaic, hydroelectric, aeolian), renewable fuels (biogas from biomass and vegetable oils, such as colza, sunflower and palm oil) or alternative fuels (biogas from waste).
Biogas
All installed cogenerators from E++ can be fed from biogas from waste, biogas from civil and industrial purification, biogas from anaerobic digestion of livestock sewage.
Since the chemical properties of biogas are particularly aggressive for the mechanical components of the cogenerator, purification is firstly carried out through dehumidification systems by refrigerators and with de-pulverizing apparatus to get rid of hydrogen sulphide in the case of biogas from purification.
Vegetable oil
If fed by this fuel, the Electrical Services Operator qualifies cogenerators as Plants Fed by Renewable Sources and so they qualify for the Green Certificate incentive.
A condition not to be set aside for having acknowledged this incentive however, is that vegetable oil does not have any chemical treatment of esterification: the only processing that can sustain oil is the squeezing out and filtration of various types of seeds (sunflower, colza, palm for example).
The particular chemical composition and physics of vegetable oil ensures that the engines that are used are modified to guarantee maximum cogeneration performance, guaranteed by E++.
Biomass from animal sewage
Livestock refluent which is mainly liquid has a percentage of dry substances that varies from 2 to 5% and a high content of COD (Carbon present), that favours the production of methane. It is collected by a pipe that starts from the barn and goes towards a tank that is sufficiently large for the yearly refluent collection. It is withdrawn from the tank and converged to the engine to produce electric and thermal energy.
Benefits
Energy and economic conservation
By using the same fuel for two different uses, cogeneration aims for a more efficient use of primary energy: the most prominent advantage is therefore the energy conservation that is achieved.
Energy and economic conservation
By using the same fuel for two different uses, cogeneration aims for a more efficient use of primary energy: the most prominent advantage is therefore the energy conservation that is achieved.
Lets make an example: with 100 units of fuel 38 units of electric energy and 45 of thermal energy are cogenerated, while by separately producing the same units of electric and thermal energy, you need 148 units of fuel. Fuel conservation is therefore about 35%.
Energy conservation deriving from rationalization naturally corresponds to economic conservation for single users. Always under an economic profile, cogeneration has investment costs that can be paid off in 36-50 months. It then requires reduced spaces and allows an increase in the safety of the electric supply and improves quality, protecting from interruptions and voltage drops.
Energy conservation deriving from rationalization naturally corresponds to economic conservation for single users. Always under an economic profile, cogeneration has investment costs that can be paid off in 36-50 months. It then requires reduced spaces and allows an increase in the safety of the electric supply and improves quality, protecting from interruptions and voltage drops.
Environment
Cogeneration is a clean technology, where alternative fuel or renewable sources are not used, it reduces the consumption of fossil fuels compared to traditional technology, therefore contributing to cutting down CO2 emissions into the atmosphere and the consequent green house effect reduction.
Cogeneration plants do not produce disposable waste and compete, thanks to rationalization in the use of heat, in alleviating pollution from heating.
The European Union defines cogeneration as the most efficient solution for:
Cogeneration is a clean technology, where alternative fuel or renewable sources are not used, it reduces the consumption of fossil fuels compared to traditional technology, therefore contributing to cutting down CO2 emissions into the atmosphere and the consequent green house effect reduction.
Cogeneration plants do not produce disposable waste and compete, thanks to rationalization in the use of heat, in alleviating pollution from heating.
The European Union defines cogeneration as the most efficient solution for:
- Rational use of primary energy sources
- Better safety in the energy supply
- A decisive reduction of emissions into the atmosphere
E++ offers
- Micro-generation up to 200 kW
- Small cogeneration up to 3000 kW
- Tri-generation
- Linked services (solution studies, administrative papers, plant development, maintenance and remote-control)
- Turnkey solutions
The bonuses of E++
- Technology: use of the best components present on the market
- Partnership: direct contact with primary cogenerator and tri-generator manufacturers
- Completeness: realization of turnkey plants that comprise study, planning, realization, administrative papers and post sales services.
- Personalization: possibility of access to special terms and tailor made maintenance services
- Integration: consolidated know-how on all renewable technology to create plants that integrate different technologies and control systems, also by remote control.
