Space heating using small-scale fluidized beds: A technoeconomic evaluation

Abstract

The technical and economic feasibility of small-scale fluidized-bed furnaces (SSFBF) for providing residential space and domestic hot water heating in Nova Scotia is analysed. A model of the provincial housing stock is developed to estimate the residential energy consumption for domestic space and hot water heating. The number of dwellings in the province is estimated from available statistical data, and the heating equipment in these dwellings is classified by type, age, and principal heating fuel. Market share levels are assumed for the new and replacement residential housing markets, and the number of SSFBFs required for those levels is calculated. The amount of coal water slurry (CWS) fuel used by the SSFBFs is calculated, and the quantities of oil, wood, and coal displaced by the CWS, as well as the number of jobs created by the adoption of SSFBF technology, are estimated. A procedure is developed to design SSFBFs in the 15–250 kW capacity range. Computer programs are developed, based on this procedure, to calculate the furnace design and performance parameters. The manufacturing cost, and the annual fuel and maintenance costs of SSFBFs are estimated, as were the capital, and annual fuel and maintenance costs of various residential heating systems. From these estimated costs, economic analyses are carried out using the annualized cost and total present worth methods. The findings of this work indicate that SSFBF technology is technically feasible, and is economically superior to conventional oil, wood and coal fired systems for residential space and domestic hot water heating.