D. Jaehnig*and W. Weiss

AEE INTEC, AEE — Institute for Sustainable Technologies, Feldgasse 19, A-8200 Gleisdorf, Austria

* Corresponding Author, d. jaehnig@aee. at

Abstract

This paper presents a method to design solar thermal systems for space heating of factory buildings using underfloor heating systems. The method uses nomograms that were expanded upon using simulations of typical system configurations. There are nomograms for two different systems configurations that can be used to determine reasonable values for collector and storage tank size for a factory building with a known heat demand.

These nomograms help to decide whether it is necessary to use a storage tank or if it makes sense to use the thermal mass of the concrete floor slab as heat store. The advantage of using the concrete floor slab is that the costs for a (often times large) storage tank can be saved. Further aspects covered are the necessity of an insulation layer underneath the floor slab and specific collector yields that can be achieved with the different system configurations. Keywords: space heating, factory buildings, design guidelines

1. Introduction

Compared to other uses in buildings such as for domestic buildings, office and administrative buildings, factory halls are characterized by high room heights of 5 to 10 meters and relatively low room temperature requirements of 15 to 18 °С.

The heating demand in industrial halls is influenced by the insulation standard of the building and to a great extent by its use. High internal thermal loads, the frequent opening of hall doors, the supply of goods with a high storage mass, all of that influences the heating of halls quite considerably. Another important element is the fact that industrial halls mostly possess a very small storage mass — apart from the concrete flooring. On the other hand floor heating for industrial halls is becoming increasingly popular which once again favors the use of solar energy due to the low required flow temperatures.

To examine the influence of the different parameters on the heating of industrial halls, a reference hall was defined and different variants were compared via a simulation. Based on the parameter studies, design nomograms were prepared for typical cases in an analogous manner to the nomograms, which are used for solar thermal plants for hot water preparation and space heating.