Buildings represent the largest share of energy demand in Switzerland. Heating, ventilation and air conditioning (HVAC) account for roughly 40% of final energy demand. 32% of national electricity demand is caused by buildings (HVAC, lighting, appliances, space heating). Therefore, the goals of the Energy Strategy 2050 and the Swiss Climate Strategy can only be met if buildings become much more energy efficient relative to the current situation, and if the remaining demand is primarily met by renewable sources.