ground, soil or water. If investmen

ground, soil or water. If investments in sustainable energy technologies are currently noteconomically viable, consider facilitating their future use. Make sure the size of heat exchangerequipment is sufficiently large to allow the use of such sustainable energies.o Use of domestic warm/hot water must be challenged. If needed, decentralized water heatersshould be used instead of warm/hot water supply from centralized boilers.o Use of thermal storages for capping consumption peaks and using energy when it is cheaper.o The results of energy performance analyses must be documented in an appropriate format(e.g., charts depicting energy consumption vs. variations of building specifications). Whenanalysing building energy consumption it is important to understand the breakdown of energyuse (e.g., lighting, cooling, heating, ventilation, etc.), so that measures can be targeted wherethe greatest and most cost-effective reductions are achievable.6.7 Initial design specificationsApply the following design specifications as initial design parameters at the earliest stages of design) togive optimization a head start. These specifications may be outperformed by optimization work thatresults in more energy efficient designs or designs yielding a higher NPV.• Building envelope (building shell):o Ratio of transparent façade to external façade for eachroom/space that require natural daylight: