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Passive principles: choosing your system

Journal Article · · Sol. Age; (United States)
OSTI ID:5554737

Passive solar space heating features (new homes or retrofits) are discussed emphasizing: (1) direct gain (south facing windows; (2) Trombe walls (or water walls); and (3) sunspace (attached greenhouse). Homes in Nashville, Denver, and Boston are considered equipped with each of the above 3 features. Performance is evaluated as total energy savings due to the addition of the solar feature divided by the total passive system area (Btu/ft/sup 2/). A typical well-insulated home is chosen as a model. Calculations are based on the Solar Load Ratio method. It is concluded that: (1) there is very little difference in annual energy contributions from direct gain (DG), sunspace (SS) or Trombe walls (TW) if the systems have night insulation; (2) without night insulation, TW and SS generally perform better than DG; (3) in warm climates (e.g. Nashville) SS is more effective because the SS can be thermally uncoupled from the house; (4) DG is a good choice for small aperture passive systems because it is inexpensive and provides light and ventilation; (5) TW is a good choice for additional aperture in excess of 6 to 8% of the floor area; and (6) SS is desirable in that relatively high cost is balanced by increased floor area provided. (MJJ)

OSTI ID:
5554737
Journal Information:
Sol. Age; (United States), Journal Name: Sol. Age; (United States) Vol. 6:12; ISSN SOAGD
Country of Publication:
United States
Language:
English