Emergy Analysis of Biomass CHP. Case Study

AbstractThis paper presents an emergy analysis in biomass cogeneration. Emergy analysis have been made for the power plant which is located in Latvia. The aim of emergy analysis is to evaluate the amount of solar emergy used in energy production.Emergy is the availability of energy (exergy) that is consumed in direct and indirect transformations required to make a product or service. The unit of emergy is solar emjoule (seJ). To calculate emergy, transformity is used to express energy units in to solar emjoules. To express other units into emergy, specific emergy, emergy per unit money, emergy per unit labor is used. Empower is defined as flow of emergy.A part of emergy analysis is the system diagram. The system diagram helps to show main inputs, outputs, components and flows between them. The system diagram of cogeneration plant is shown in figure. Several inputs as renewable, non-renewable, labour and economical have been taken in account in emergy analysis. System diagram shows main flows between inputs and components of the system. All inputs and outputs are converted in emjoules. Finally, emergy indicators such as renewable fraction, emergy yield ratio, emergy sustainability index, etc. are calculated