On the usefulness of a cost-performance indicator curve at the strategic level for consideration of energy efficiency measures for building portfolios

Abstract

There is an increasing desire by managers to reduce the amount of energy consumed by the buildings in their portfolio. Energy efficiency measures on existing buildings, however, are often economically feasible only if executed at the same time as the execution of necessary maintenance and refurbishment measures. At the strategic level it would be useful to be able to better plan the costs and benefits of energy efficiency measures so that decisions could be made to execute them when the opportunity arises.In this paper, a Cost-Performance-Indicator (CPI) curve is proposed to indicate additional costs and benefits of energy efficiency measures at a strategic level, and evidence is given that corroborates the hypothesis that energy efficiency measures follow the law of increasing relative costs. The usefulness of the CPI curve is demonstrated through two case studies. An example is provided and the potential is discussed for using this curve for the planning and budgeting of refurbishment and energy efficiency measures, and as a tool to explain the relation between costs and benefits of measures enhancing building energy efficiency, including the production of renewable energy, to investors.

Holger Wallbaum

Full Professor, Vice-Head of Department and Vice-Dean for Research

Holger is a Full Professor in sustainable building at the Division of Building Technology, research group Sustainable Building, and in the Area of advance Building Futures. Holger works within sustainable building on concepts, tools and strategies to enhance the sustainability performance of construction materials, building products, buildings as well as entire cities.