Calculation of climatic solar heating performance

A climatic design method is presented which uses the long-term outdoor temperature distribution as well as utilzability of irradiation to find the solar fraction for building heat. The method considers a solar heater to be able, on the average, to supply all the heat needed by a building down to a cut-in temperature determined by the average amount of solar heat collected and the heat loss coefficient of the building. The amount of auxiliary heat needed is calculated from the kelvin day value below this cut-in temperature. The method permits the use of temperature distributions obtained from long records so that extremes can be represented. This allows calculations to be made near 100% solar heat. Any thermostat setting can be used. Several heat sources can be used. Examples are given.