Energy and Buildings 86 (2015) 478–491 Contents lists available at ScienceDirect Energy and Buildings j ourna l ho me pa g e: www.elsevier.com/locate/enbuild Realisable 10-year reductions in European energy consumption for air conditioning Roger Hitchin ∗ , Christine Pout, David Butler Building Research Establishment, Watford, Hertfordshire WD25 9XX, United Kingdom a r t i c l e i n f o Article history: Received 23 April 2014 Received in revised form 15 October 2014 Accepted 21 October 2014 Available online 31 October 2014 Keywords: Air conditioning Energy policy Energy savings a b s t r a c t This paper summarises the results of a study to identify and quantify the potential impact of measures and policies to reduce the energy consumption of air conditioning in European countries over a 10-year period. The market penetration of air conditioning in Europe has increased steadily over several decades. On a “business as usual” basis, its energy consumption would increase by over 50% by 2020. Measures to restrict this increase are therefore important, but the savings potential straddles several overlapping areas which are subject to different constraints including those imposed by the replacement rates of systems and products, and the refurbishment rates of existing buildings. This work reported in this paper is based on the use of information from a variety of sources in a highly disaggregated model to assess the “realisable” savings over a 10-year period, taking into account relevant constraints. The paper summarises results at a European level, focussing on those cases that generate the great- est realisable savings. Savings are possible in three areas: improved equipment and system efficiency, reduced cooling loads, and more effective operation. The cases that offer the largest savings provide the basis for recommendations for policy measures, often using existing policy instruments. In addition, areas where further work is needed are identified. More detailed results and information about the study and additional recommendations can be found at http://www.bre.co.uk/searchresults.jsp?category=5&q=energy+management [1]. © 2014 Elsevier B.V. All rights reserved. 1. Introduction The ownership levels of air conditioning in Europe have been rising steadily for five decades or so, and further increases are expected over the next two or three decades at least. Other things being equal, this could result in an increase of air-conditioning related energy consumption of over 50% by 2020 [2]. This pro- jected growth in consumption runs counter to the general policy objectives of reducing energy consumption and the associated greenhouse gas emissions. We estimate annual energy consump- tion for air conditioning in Europe in 2010 to have been about 140 TWh. Of this about 80 TWh is used to produce cooling, with the remainder being used to transfer this cooling to the areas of buildings where it is required – mostly by fans used to move air. This paper addresses several related questions: ∗ Corresponding author. Tel.: +44 0192364773. E-mail addresses: hitchinr@bre.co.uk (R. Hitchin), poutc@bre.co.uk (C. Pout), butlerd@bre.co.uk (D. Butler). - By how much could European energy consumption for air- conditioning be reduced over a 10-year timescale? - How much could different policy instruments contribute? - Do the existing policy instruments leave any significant gaps? It addresses savings that could result from: reductions in cool- ing loads, the use of more efficient systems and better system operation and maintenance. The measures that would reduce air conditioning energy consumption apply to new buildings or require the replacement of existing systems and components or modifica- tions to existing buildings. This imposes significant constraints on realistic implementation rates: realisable savings accumulate rela- tively slowly. At the same time, the ownership of air conditioning is increasing both in new and existing buildings and so both the energy consumption and the potential for savings increase over time. The policy objective of constraining (ideally of reducing) the energy use for air conditioning is therefore inherently one that must consider changes over periods of several decades. On the other hand, over such long periods many things can change, often http://dx.doi.org/10.1016/j.enbuild.2014.10.047 0378-7788/© 2014 Elsevier B.V. All rights reserved.