Editing Passive solar building design (section)

===Passive solar design on skyscrapers===
There has been recent interest in the utilization of the large amounts of surface area on skyscrapers to improve their overall energy efficiency. Because skyscrapers are increasingly ubiquitous in urban environments, yet require large amounts of energy to operate, there is potential for large amounts of energy savings employing passive solar design techniques. One study,<ref>{{Cite journal|last=Lotfabadi|first=Pooya|title=Solar considerations in high-rise buildings|url=https://www.researchgate.net/publication/271226417|journal=Energy and Buildings|volume=89|pages=183–195|doi=10.1016/j.enbuild.2014.12.044|year=2015|bibcode=2015EneBu..89..183L }}</ref> which analyzed the proposed [[22 Bishopsgate]] tower in London, found that a 35% energy decrease in demand can theoretically be achieved through indirect solar gains, by rotating the building to achieve optimum ventilation and daylight penetration, usage of high thermal mass flooring material to decrease temperature fluctuation inside the building, and using double or triple glazed low emissivity window glass for direct solar gain. Indirect solar gain techniques included moderating wall heat flow by variations of wall thickness (from 20 to 30&nbsp;cm), using [[Glazing (window)|window glazing]] on the outdoor space to prevent heat loss, dedicating 15–20% of floor area for thermal storage, and implementing a [[Trombe wall]] to absorb heat entering the space. Overhangs are used to block direct sunlight in the summer, and allow it in the winter, and heat reflecting blinds are inserted between the thermal wall and the glazing to limit heat build-up in the summer months.

Another study<ref>{{Cite journal|last1=Wong|first1=Irene|last2=Baldwin|first2=Andrew N.|date=2016-02-15|title=Investigating the potential of applying vertical green walls to high-rise residential buildings for energy-saving in sub-tropical region|journal=Building and Environment|volume=97|pages=34–39|doi=10.1016/j.buildenv.2015.11.028|bibcode=2016BuEnv..97...34W |hdl=10397/44174|hdl-access=free}}</ref> analyzed double-green skin facade (DGSF) on the outside of high-rise buildings in Hong Kong. Such a green facade, or vegetation covering the outer walls, can combat the usage of air conditioning greatly - as much as 80%, as discovered by the researchers.

In more temperate climates, strategies such as glazing, adjustment of window-to-wall ratio, sun shading and roof strategies can offer considerable energy savings, in the 30% to 60% range.<ref>{{Cite journal|last1=Raji|first1=Babak|last2=Tenpierik|first2=Martin J.|last3=van den Dobbelsteen|first3=Andy|title=An assessment of energy-saving solutions for the envelope design of high-rise buildings in temperate climates: A case study in the Netherlands|journal=Energy and Buildings|volume=124|pages=210–221|doi=10.1016/j.enbuild.2015.10.049|year=2016|bibcode=2016EneBu.124..210R |url=http://resolver.tudelft.nl/uuid:cb563c4f-27ec-461e-ae1d-b2bc023a4843 }}</ref>