Identifying energy saving opportunities in a process plant through preliminary energy audit

Abstract

Improving plant energy efficiency requires monitoring, analysis and adjustments of the appropriate plant operating parameters and in some cases, plant modifications. This involves studies of plant energy distribution and the corresponding losses associated with the various uses of energy. The scope and duration of a study may vary depending on the complexity of a plant and various operational requirements and constraints. The recommended practice is to run a preliminary energy audit on a plant before conducting a detailed retrofit project. Such exercise helps plant managers to differentiate between the immediate energy saving potentials from those requiring either some investments or further studies. This paper outlines the methodology and the scope involved in a preliminary study to improve overall plant energy efficiency. The procedure includes plant familiarization, data collection and parameter measurement, analysis of energy consumption and losses in the various sections of a process plant, analysis of the results and recommendation of measures supported by economic justifications. Examples of studies completed for two different plants are also presented.