Anne Grete Hestnes

Building Integration Of Solar Energy Systems

Abstract The way solar systems are used in buildings is different from what it used to be. Buildings are no longer designed to use just passive solar energy systems, such as windows and sunspaces, or active solar systems, such as solar water collectors. In fact, the words passive and active no longer make sense, as the newer buildings combine several of these technologies. They may be both energy efficient, solar heated and cooled, and PV powered, i.e. they are simply “solar buildings”. The paper discusses the various approaches in building integration of solar systems, and presents a number of successful examples. It also presents some of the work being done on improving the design processes to account for the need for a holistic approach to solar building design.

Solar versus green : The analysis of a Norwegian row house

There are, presently, two schools of thought when it comes to designing buildings that promote sustainable development. One school emphasizes materials use and «green» buildings, while the other one emphasizes energy use and low energy/solar buildings. The promoters of «green» buildings often claim that the reduced energy use during operation of the solar and low energy buildings is counteracted by the increased embodied energy in these buildings. The paper describes the results of a study of embodied energy and energy use in operation in a wooden row house. The house, designed and built as a solar house with very low energy consumption during operation, is located i Hamar, in southern Norway. In the study, the built version is compared with four other versions: two versions where the house is designed according to the requirements of the new Norwegian Building Code, one version where the house is designed according to present constuction and insulation standards in Norway, and one version where the house is designed according to principles used by the architects presently designing «green» buildings in Norway. The results of the study, whih are compared with some results from abroad, show that the solar building has a lower overall energy use, when both embodied energy and energy use during operation is taken into account. Also, it shows that there is less difference between the approaches of the two schools of thought than is sometimes believed. The best buildings are generally those that are both solar, low energy, and «green».

Effective retrofitting scenarios for energy efficiency and comfort: results of the design and evaluation activities within the OFFICE project

Abstract This paper describes the results of the evaluation of a set of retrofitting strategies designed for ten existing office buildings. The work was carried out by the Design and Evaluation Group in the project “OFFICE - Passive Retrofitting of Office Buildings to Improve thier Energy Performance and Indoor Working Conditions” funded by the European Commission under the JOULE III Programme. The objective of the OFFICE project was to promote passive solar and energy efficient retrofitting measures in office buildings. This was done by examining different low energy retrofitting measures in terms of energy, indoor environment, and economy, and by using this as a basis for the development of general retrofitting strategies and design guidelines. The ten European office buildings included in the project are situated in Denmark, England, France, Germany, Greece, Italy, Norway, Sweden, and Switzerland, and the results show that it is possible to significantly reduce the use of purchased energy in existing office buildings in all these countries by using passive and low energy technologies.

The use of transparent insulation in low energy dwellings in cold climates

Abstract This article discusses the use of transparent insulation materials in low energy dwellings in cold climates. Both aesthetic and thermal issues for the capillary type of transparent insulation material are investigated. In Lien (1995) granulated silica aerogel and multilayered material of corrugated sheets are also presented. To investigate the aesthetic qualities of the material, a scale model study is performed. The study treats the distribution of daylight, the visual contact through the materials, and the appearance of the materials. The results show, among other things, that the capillary material spreads direct daylight in a cone shape and distributes it to certain areas of the floor, walls, and ceiling of a room. The visual contact through the materials is limited and dependent on the thickness of the material, the illumination situation, the distance between the observer and the material and the object observed, and the angle of direction at which the observer looks through the material. Calculations of the energy consumption for heating and ventilation are performed for a row house with different sizes of materials. The calculations are done for two climate zones in Norway. The results show that energy savings in the order of 20% can be attained. The results are especially promising for the coldest climate zone, where the problem of overheating is small and the energy saving potential is still good.

Renovation status and technical condition of Norwegian dwellings

Purpose – The purpose of this paper is to gain knowledge on the renovation status for Norwegian dwellings that can be used to design attractive energy efficiency measures. Norwegian dwellings are exposed to a windy, cold and moist climate and the technical condition of existing dwellings depend on the owners priorities regarding maintenance and renovation. The paper focuses on the renovation status and technical condition of privately owned detached houses built in Norway in the 1980s constituting 10 per cent of the total Norwegian dwelling stock. These houses are high-energy spenders and are at a stage in their lifetime where major renovation such as new windows and ventilation system is expected. Design/methodology/approach – The status for redecoration, maintenance and renovation as well as the technical condition of 91 dwellings are mapped and analysed. Findings – An analysis of the empirical data identified four categories of houses when considering home upgrades and technical condition: the as built...