HORTEB - Planningprogram for greenhouse heating by biomass fuels - Part 2:Analysis of the parameter contains in the program

At the Institute for Horticultural and Agricultural Engineering of the Univ ersity of Hannover the planning program HORTEB ("Horticultural Energy Suppl y with Biomass") was developed (BROKELAND 1998). With this program the ener getic use of biomass for heat production can bet planned with consideration of complete process engineering chains. This investigation and the creatio n of the program were financed by the Federal Minstry for Food, Agriculture and Forestry. The first part of this article described the basics, the seq uence of the program and the including parameters. Part 2 presents the resu lts of an analysis of the parameters. The parameters which are received in the planning program HoRTEB were teste d in analyses of sensitivity in their effect on the heat production costs. The most important factor, which determines the economy of a biomass firing , is the fuel oil price and the price for natural gas. Further important ef fects on the heat production costs have the mode of operation of the firing unit (monovalent or bivalent), the unit size and the service life. The eff ect of the heat requirement decreases with increasing size of the firing un it. The interest rate does have also a great effect on the heat production costs like all foreign financed investments do. On the other hand the heat production costs increase relatively low with increasing transportation dis tance. Nevertheless transportation distances should be as short a as possib le to avoid environmental impacts such as exhaust gases, noise and increase d traffic volume.