Building services in energy-efficient buildings

There are generally two approaches to an energy-efficient building. On the one hand, the aim is to reduce the energy demand by using suitable structural measures. This means coordinating the structure, construction and building materials in such a way as to minimise the use of technical equipment. The second approach is to select and design technical equipment in such a way that the transformation and distribution of energy is performed efficiently. One might refer to these two approaches as low-tech and high-tech. In practice, a combination of the two usually leads to the best results.

In every building, there are five services to consider in terms of energy efficiency, namely heating, cooling, ventilation, lighting and electricity.

	Low-tech	High-tech
Heating	Retain heat produced by central heating, solar irradiation and ambient heat through insulation and storage mass.	Supply heat efficiently in a low carbon or even carbon-neutral way through technical equipment.
Cooling	Avoid overheating through structural measures, e.g. sun protection.	Remove heat efficiently by using natural heat sink or refrigerating machines run on regenerative power.
Ventilation	Ventilate space naturally, e.g. night-time ventilation.	Supply air efficiently with mechanical support and using heat exchangers.
Lighting	Make use of daylight.	Provide artificial light with minimum energy consumption and using an automated system.
Electricity	Apply efficient electrical equipment.	Make use of the building and the site to generate power, e.g. solar panels can replace roof covering or facade elements.