Factors Governing the Selection of Co-generation System
Q. State and explain the factors that govern the selection of co-generation system for an industry.
- Heat to power ratio : The heat to power ratio of consuming system should match with the characteristics of of co-generation system the co-generation system. It is represented on the basis of energy unit (kW). Heat power ratio = Heat energy / Electricity required
- Load pattern : It is necessary to consider the load pattern for the heat and power demand, while selecting the type of co-generation system.
- Type of fuel available : The selection of co-generation system also depends upon the type of fuel available for the system. If the cost of fuel available for the system is low then the co-generation system selected give best results.
- Quality of thermal energy required : The quality of thermal energy required depends upon the temperature and pressure, hence it has a predominant role in determination of type of co-generation system.
- System reliability : In case of a particular power consuming the co-generation system reliability is met important factor. If suppose a very important step is involved in the power consuming system to which unavailability of co-generation system may not be able to bear, in such cases, Co-generation system to be installed must be modular.
- Electricity Buy-back : At the time of designing a co-generation system, we are required to know and think for the local regulations for the buying of electricity from the co-generating system and selling of electricity to co-generation system.
- Grid dependent system and independent system : The technical configuration of grid dependent as co – generation system is also dependent upon this factor.
- Local environmental regulations : The type of fuel used will have different effects on environment that is if wood is used as fuel for boilers it will develop more pollution in comparison to coal. A still further reduction particular fuel, we have to see the environmental rules in that region. The environmental rules in urban areas may be different than sub-urban areas and villages. In addition to above factors following are some of factors which influence the selection of co-generation system.
- Base electrical load matching : The co-generation system is designed to supply the base of minimum electricity demand for the system. The remaining demand of power is purchased from the utility grid. This type of co-generation is used for the required thermal energy.
- Base thermal load matching : The co-generation system is designed to supply the minimum thermal i.e. the base thermal energy requirement when the demand of heat is more than the base or minimum.
- Electrical load matching : For such cases, where all the load requirement is to be supplied by the stand-by boilers are used. co-generation system, the co – generators are designed in such a manner that total electricity required is generated and supplied by it. Therefore, this co- generation system is totally independent of the electricity utility grid and is called as ‘ stand alone system. Sometimes if required auxiliary boilers are used for heat energy
- Thermal load matching : In this case, the co-generation system is designed in such a manner that it will generate the total heat energy required for the purpose, if required electricity may be purchased from the utility grid.