@article{BourikasJamesBahajetal.,
  author    = {Bourikas, Leonidas and James, Patrick A. B. and Bahaj, AbuBakr S. and Jentsch, Mark F. and Shen, Tianfeng and Chow, David H. C. and Darkwa, Jo},
  title     = {Transforming typical hourly simulation weather data files to represent urban locations by using a 3D urban unit representation with micro-climate simulations},
  series = {Future Cities and Environment},
  journal   = {Future Cities and Environment},
  doi       = {10.1186/s40984-016-0020-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170418-31348},
  abstract  = {Urban and building energy simulation models are usually driven by typical meteorological year (TMY) weather data often in a TMY2 or EPW format. However, the locations where these historical datasets were collected (usually airports) generally do not represent the local, site specific micro-climates that cities develop. In this paper, a humid sub-tropical climate context has been considered. An idealised "urban unit model" of 250 m radius is being presented as a method of adapting commonly available weather data files to the local micro-climate. This idealised "urban unit model" is based on the main thermal and morphological characteristics of nine sites with residential/institutional (university) use in Hangzhou, China. The area of the urban unit was determined by the region of influence on the air temperature signal at the centre of the unit. Air temperature and relative humidity were monitored and the characteristics of the surroundings assessed (eg green-space, blue-space, built form). The "urban unit model" was then implemented into micro-climatic simulations using a Computational Fluid Dynamics - Surface Energy Balance analysis tool (ENVI-met, Version 4). The "urban unit model" approach used here in the simulations delivered results with performance evaluation indices comparable to previously published work (for air temperature; RMSE <1, index of agreement d > 0.9). The micro-climatic simulation results were then used to adapt the air temperature and relative humidity of the TMY file for Hangzhou to represent the local, site specific morphology under three different weather forcing cases, (ie cloudy/rainy weather (Group 1), clear sky, average weather conditions (Group 2) and clear sky, hot weather (Group 3)). Following model validation, two scenarios (domestic and non-domestic building use) were developed to assess building heating and cooling loads against the business as usual case of using typical meteorological year data files. The final "urban weather projections" obtained from the simulations with the "urban unit model" were used to compare the degree days amongst the reference TMY file, the TMY file with a bulk UHI offset and the TMY file adapted for the site-specific micro-climate (TMY-UWP). The comparison shows that Heating Degree Days (HDD) of the TMY file (1598 days) decreased by 6 \% in the "TMY + UHI" case and 13 \% in the "TMY-UWP" case showing that the local specific micro-climate is attributed with an additional 7 \% (ie from 6 to 13 \%) reduction in relation to the bulk UHI effect in the city. The Cooling Degree Days (CDD) from the "TMY + UHI" file are 17 \% more than the reference TMY (207 days) and the use of the "TMY-UWP" file results to an additional 14 \% increase in comparison with the "TMY + UHI" file (ie from 17 to 31 \%). This difference between the TMY-UWP and the TMY + UHI files is a reflection of the thermal characteristics of the specific urban morphology of the studied sites compared to the wider city. A dynamic thermal simulation tool (TRNSYS) was used to calculate the heating and cooling load demand change in a domestic and a non-domestic building scenario. The heating and cooling loads calculated with the adapted TMY-UWP file show that in both scenarios there is an increase by approximately 20 \% of the cooling load and a 20 \% decrease of the heating load. If typical COP values for a reversible air-conditioning system are 2.0 for heating and 3.5 for cooling then the total electricity consumption estimated with the use of the "urbanised" TMY-UWP file will be decreased by 11 \% in comparison with the "business as usual" (ie reference TMY) case. Overall, it was found that the proposed method is appropriate for urban and building energy performance simulations in humid sub-tropical climate cities such as Hangzhou, addressing some of the shortfalls of current simulation weather data sets such as the TMY.},
  subject      = {Mikroklima},
  language  = {en}
}
@article{JentschKulleBodeetal.,
  author    = {Jentsch, Mark F. and Kulle, Christoph and Bode, Tobias and Pauer, Toni and Osburg, Andrea and Namgyel, Karma and Euthra, Karma and Dukjey, Jamyang and Tenzin, Karma},
  title     = {Field study of the building physics properties of common building types in the Inner Himalayan valleys of Bhutan},
  series = {Energy for Sustainable Development 38},
  journal   = {Energy for Sustainable Development 38},
  doi       = {10.25643/bauhaus-universitaet.3139},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170419-31393},
  pages     = {48 -- 66},
  abstract  = {Traditionally, buildings in the Inner Himalayan valleys of Bhutan were constructed from rammed earth in the western regions and quarry stone in the central and eastern regions. Whilst basic architectural design elements have been retained, the construction methods have however changed over recent decades alongside expectations for indoor thermal comfort. Nevertheless, despite the need for space heating, thermal building performance remains largely unknown. Furthermore, no dedicated climate data is available for building performance assessments. This paper establishes such climatological information for the capital Thimphu and presents an investigation of building physics properties of traditional and contemporary building types. In a one month field study 10 buildings were surveyed, looking at building air tightness, indoor climate, wall U-values and water absorption of typical wall construction materials. The findings highlight comparably high wall U-values of 1.0 to 1.5 W/m²K for both current and historic constructions. Furthermore, air tightness tests show that, due to poorly sealed joints between construction elements, windows and doors, many buildings have high infiltration rates, reaching up to 5 air changes per hour. However, the results also indicate an indoor climate moderating effect of more traditional earth construction techniques. Based on these survey findings basic improvements are being suggested.},
  subject      = {Luftdichtheit},
  language  = {en}
}