Techno-economic performance analysis of energy production from biomass at different scales in the UK context

This paper compares the results of a techno-economic performance analysis of three combustion plants for the recovery of energy from three types of biomass: solid recovered fuel (SRF), forestry waste wood chips (FWWC), and crude rape seed oil (RSO). Small and medium scale plants have been investigated, 50 kilo tonnes per annum (ktpa) and 160 ktpa combustion plants utilising FWWC, 50 ktpa and 100 ktpa plants treating SRF, and an internal combustion engine plant at 27 ktpa and 40 ktpa utilising RSO. The technical assessment includes calculations for electricity generation, heat produced and overall system efficiency. The economic viability of the different processes is investigated through a discounted cash flow analysis. The levelised cost is used to calculate the cost of production of one unit of electricity. The effect of changing model input parameters on the economic performance is evaluated. Seven different system variables have been chosen and the effect of a ±10% change on the levelised cost has been examined. The results showed that the levelised cost of the SRF plant is mainly affected by calorific value, turbine efficiency, capital and operating costs. The parameters which affect the FWWC biomass plant are the calorific value, steam turbine efficiency, capital and operating costs. Whereas, parameters affecting the RSO biomass plant are the calorific value, engine efficiency, capital and operating costs. A techno-economic analysis of the plants indicates the SRF plant is economical at both scales. The RSO plant and the FWWC plant are only economical at the medium scales investigated. The 40 ktpa RSO plant is found to be the most efficient one at 52% compared with 28% efficiency for the SRF plant, it is also the most economically viable option with a 25% IRR compared to 17% IRR for the FWWC plant, and 10% IRR for the SRF plant.