Passivehouses in Europe with a specific energyrequirement of less than 30kWh/(m2a) total for heating, tap warm water, ventilation and household electricity have been realized in Darmstadt, FRG. Four families live in the dwellings with extreme thermal insulation, heat recovery and optimized use of passive solar energy. The measurement program includes more than 200 sensors; temperatures, comfort, energy flows, air flows and indoor air quality are monitored. With dynamic simulation comprising about 2000 cases of alternative design of the building components the project was optimized.
Intermittent heating patterns, characteristic of Israel and other countries with a mild winter enable energy · conservation at the expense of very high peak energy consumption; · very low levels of thermal comfort; and surface condensation and mould growth problems. The paper summarizes a research project which included analysis of total daily energy consumption, partial energy during evening (peak) hours, weighted cost of total energy, improved thermal comfort, internal surface temperatures -of the external envelope, and surface temperatures of partitions.