Can qualitative methods support the development of more flexible and energy saving thermal comfort?

This paper uses examples from a Swedish study to suggest some ways in which cultural variation could be included in studies of thermal comfort. It is shown how only a slight shift of focus and methodological approach could help us discover aspects of human life that add to previous knowledge within comfort research of how human beings perceive and handle warmth and cold. It is concluded that it is not enough for buildings, heating systems and thermal control devices to be energy-efficient in a mere technical sense. If these are to help to decrease, rather than to increase, energy consumption, they have to support those parts of already existing habits and modes of thought that have the potential for low energy use. This is one reason why culture-specific features and emotional cores need to be investigated and deployed into the study and development of thermal comfort.

Comparison of two HVAC renovation solutions : A case study

Within the aging building stock of Europe, there is great potential of saving energy through renovation and upgrading to modern standards, and to thereby approach the internationally set goals of lower energy use. This paper concerns the planned renovation of the building envelope and HVAC systems in a multi-family house in Ludwigsburg, Germany. Five systemic HVAC solutions were compared, with special focus on two systems: A) Balanced ventilation with HRC + Micro heat pump, and B) Forced exhaust ventilation + Heat pump with exhaust air HRC + Ventilation radiators. Given the predicted heating demand and ventilation rate of the house after renovation, the performance of the two systems was compared, alongside three common systems for reference. Calculations were made using TMF Energi, a tool developed by SP Technical Research Institute of Sweden.    Both systems A and B were found to have the lowest electrical energy use together with the ground source heat pump system for the assumed conditions. For other assumptions, including different climate and degree of insulation, some differences between these three systems were noted. Most significant is the increased electrical use of system B for higher heating loads due to limitations in the power available from the heat source, exhaust air, which is dependent on the ventilation rate.

Energy efficient and economic renovation of residential buildings with low-temperature heating and air heat recovery

With the building sector accounting for around 40% of the total energy consumption in the EU, energy efficiency in buildings is and continues to be an important issue. Great progress has been made in reducing the energy consumption in new buildings, but the large stock of existing buildings with poor energy performance is probably an even more crucial area of focus. This thesis deals with energy efficiency measures that can be suitable for renovation of existing houses, particularly low-temperature heating systems and ventilation systems with heat recovery. The energy performance, environmental impact and costs are evaluated for a range of system combinations, for small and large houses with various heating demands and for different climates in Europe. The results were derived through simulation with energy calculation tools. Low-temperature heating and air heat recovery were both found to be promising with regard to increasing energy efficiency in European houses. These solutions proved particularly effective in Northern Europe as low-temperature heating and air heat recovery have a greater impact in cold climates and on houses with high heating demands. The performance of heat pumps, both with outdoor air and exhaust air, was seen to improve with low-temperature heating. The choice between an exhaust air heat pump and a ventilation system with heat recovery is likely to depend on case specific conditions, but both choices are more cost-effective and have a lower environmental impact than systems without heat recovery. The advantage of the heat pump is that it can be used all year round, given that it produces DHW. Economic and environmental aspects of energy efficiency measures do not always harmonize. On the one hand, lower costs can sometimes mean larger environmental impact; on the other hand there can be divergence between different environmental aspects. This makes it difficult to define financial subsidies to promote energy efficiency measures.