Aerial thermography for district heating systems application: an evaluation of commercial thermography

Abstract

For district heating networks, practical applications of aerial thermography involve problems usually neglected in the process of research and methodological development. This process is usually initiated by first examining physical conditions for the specific application. Then is developed a method designed for the application. However, there should also be a test of the thermographic method in practice, including both an operational and economical evaluation of different stages of the application, suggesting feasible changes of the method and of the operational organisation. Experience from thermographic studies performed in the Scandinavian countries implies that follow-up studies are necessaiy when introducing high tech methods for practical applications. This kind of studies gives experience in major problems connected to different operational conditions, and makes it possible to avoid failures and to optimise the use of the information of the thermographic method. This paper deals mainly with the evaluation of aerial thermography for district heating networks applications. The main conclusions are that aerial thermography can contribute to an efficient operation of district heating systems, and the method is sufficiently developed for commercial use. However, the method could be improved by ensuring a feedback from the utility to the thermography consultant, so that analysis and interpretation routines, and presentation of results, may be further adjusted to user requirements. Also, increasing the knowledge possessed by the consultant and maintenance personnel regarding technical properties of culvert systems and thermographic methods, would result in more efficient procedures.