Energy Futures: Managing Bulimia or Anorexia

24-25 Jun

Buildings for low energy air conditioning

Over half of global warming is thought to be attributable to the burning of fossil fuelsand slightly less than half of this is due to conditioning the environment withinbuildings. Since the UK government is committed to reducing carbon dioxideemissions by 20% between the years1990 and 2010, the pressure to improve theenergy efficiency of our building stock is likely to increase in the coming years.Field studies have identified that, on average, fuel costs for air conditioned buildingsare twice that of naturally ventilated buildings and result in twice the CO2 emissions1.Air conditioning is therefore often thought of as an environmental evil byenvironmentalists with calls to ban it. Air conditioning protagonists argue that airconditioning provides for a better environment within buildings and only accounts for6% of CO2 emissions in commercial and public buildings (i.e. 1% of total UK CO2emissions).This chapter explores some of the issues that can impact on the design of energyefficient air-conditioned buildings. The arguments presented in this chapter are basedon research carried out at the Bartlett, University College London (UCL) and on theauthors? experience of running the Department of Trade and Industry funded EnergyDesign Advice Scheme (EDAS) office based at UCL. EDAS provides free advice toany building professional involved in the design and/or commissioning of a newbuilding or refurbishment of an existing building. The office based at the Bartlett hasbeen involved in providing advice on over 700 projects with predicted cumulativeenergy savings for the scheme as a whole of £15 million per annum

Architects need environmental feedback

The role of environmental feedback within architects' offices is examined as a fundamental ingredient of sustainability. Three case study buildings are examined using a feedback exercise encompassing the whole building process from early key design decisions to occupation. Results show that sometimes design decisions are taken for aesthetic reasons without certainty on their environmental impact. Improvements are possible especially in energy consumption, glare, the usability of controls, the communication of strategies and comfort conditions. The architects report the feedback lessons relevant for their work. A systematic approach to project feedback is proposed with emphasis in feeding forward to new projects and recording decision-making. To close the information loop, briefs need explicitly to mention performance targets for energy use, management expectations, control requirements and to promote feedback itself

UK domestic air conditioning: a study of occupant use and energy efficiency

This paper presents the results of a study of air-conditioning usage in homes in the southeast of England. First part of the study consisted surveying 13 dwellings with air-conditioning for a series of 4 week periods during the summer of 2004. The second part involved testing energy efficiency of “single-split” and “portable” air-conditioning units under “in-use” conditions. Data on usage patterns and typical temperature profiles during operation was collected and is presented here. Temperatures at which users switched their units on were, on average, 24-25oC, while typical running times for a single operation were found to be around 5 hours during daytime and 7 hours at night in bedrooms. The study also indicated high occupant satisfaction rates with split-units. An unexpectedly high overall energy efficiency ratio (EER), of 5-10, was found for the single-split unit tested during the relatively mild autumn weather. However, a very poor EER, of less than 1, was found for the portable unit tested. Further work is needed to increase the reliability and statistical significance of the results

Air pollutant levels in air-conditioned and naturally ventilated museums: a pilot study

An air-conditioned and a naturally ventilated museum in a highly polluted part of London were compared for effectiveness of pollution control. Nitrogen dioxide, sulphur dioxide and hydrogen sulphide concentrations were measured inside and outside using diffusion tubes. Airborne particles were measured using a Grimm laser counting device. It was found that the benefits normally attributed to air-conditioning with filtration were not as great as might be thought. Only nitrogen dioxide and particle levels were significantly lower in the air-conditioned museum than in the naturally ventilated museum

Preventive conservation strategies for sustainable urban pollution control in museums

The last 40 years have seen major changes in the sources and concentrations of urban pollution (nitrogen dioxide, sulfur dioxide, hydrogen sulfide, and particulates). During this time, research has advanced our understanding of the impact of pollutants on objects in urban museums. As a consequence, pollutant control has become an important aspect of preventive conservation. There is also increased awareness of the need for pollution control strategies that are sustainable at an organizational and global level. This report, prepared by a chemist, a conservator, and two building scientists, reviews strategies for minimizing the impact of urban pollution on museum collections. The results of new research funded by the UK government identify current (1999) internal pollution levels in both naturally ventilated and air-conditioned museums with particle and gaseous filtration, in relation to external concentrations, ventilation strategies, and the characteristics of the internal fabric and finishes of these buildings. The last 40 years have seen major changes in the sources and concentrations of urban pollution (nitrogen dioxide, sulfur dioxide, hydrogen sulfide, and particulates). During this time, research has advanced our understanding of the impact of pollutants on objects in urban museums. As a consequence, pollutant control has become an important aspect of preventive conservation. There is also increased awareness of the need for pollution control strategies that are sustainable at an organizational and global level. This report, prepared by a chemist, a conservator, and two building scientists, reviews strategies for minimizing the impact of urban pollution on museum collections. The results of new research funded by the UK government identify current (1999) internal pollution levels in both naturally ventilated and air-conditioned museums with particle and gaseous filtration, in relation to external concentrations, ventilation strategies, and the characteristics of the internal fabric and finishes of these buildings