At the end of 2023, the 28th Climate Change Conference reached an agreement that the improvement in energy efficiency should double every year [5]. Energy efficiency measures enjoy political and financial support since, together with decarbonization measures, they form the basis for the energy transition. The German Government supports companies, local authorities and private households in improving their energy balance, and promotes the use of innovative and efficient (cross-sectional) technologies in practice. Energy savings through the exploitation of recovered waste heat are also supported.
The German Energy Efficiency Act requires public authorities, companies and data centres to take energy-saving measures in line with EU rules as of 2024. Companies with an annual consumption of 15 GWh or more are obliged to introduce energy or environmental management systems and make their energy efficiency public. In addition, companies will be required in future to avoid or utilize waste heat from production. Data centres will be subject to energy efficiency standards [6].
Germany’s Energy Efficiency Strategy 2050 (EffSTRA) sets a 30% reduction in primary energy consumption by 2030 (from a 2008 baseline) as a national energy efficiency target, and compiles the measures required for this purpose in a National Action Plan on Energy Efficiency (NAPE 2.0). The measures concern the sectors of buildings, industry, the craft trades, commerce and services, transport and agriculture. By improving energy efficiency, the aim is not only to protect the environment and the climate, but also to promote modernization and innovation processes in all sectors, open up new markets, and improve export opportunities [7].
The German government also supports the formation of energy efficiency networks. To date, 333 of these networks have been formed, in which industry, the craft trades and commerce combine their measures and pool expertise [8].
Numerous efficiency measures are already being implemented in companies. In the future, the task will be to roll them out on a wide scale, with political support. Examples of these measures are: energy audits, moving data from local servers to the cloud, electrifying commercial vehicles, switching from gas boilers to heat pumps, using well-maintained heat exchangers, installing sensors and digital energy monitors to detect power consumption in standby mode, using digital twins to simulate efficiency measures without interrupting production, and implementing smart building solutions to control the power supply, lighting, blinds, heating, ventilation and air conditioning [9].
The digital transformation is one of the most important trends for the world of work and society, and can also support energy efficiency measures. However, according to a survey conducted among companies, considerable untapped potential still exists in many sectors for digital technologies to be used to improve energy efficiency. The survey shows that as yet, companies have tended to be hesitant to use digital technologies to reduce energy consumption, particularly in the areas of buildings and production, where consumption is high. To exploit the potential of digitalization to deliver savings for private households and the economy to the full, harmonized standards and interfaces for data collection and processing must be established, and data protection issues clarified [10].
At the same time, digital technologies themselves have a high direct energy consumption. This consumption is almost impossible to quantify accurately; studies vary widely in their estimates of the energy requirements of digital applications. A large proportion of demand is due to the sharp rise in the number of private terminal devices. Data centres and data transmission networks are also major consumers of energy, however. The energy demand of data centres is growing enormously, particularly owing to artificial intelligence (AI). According to experts, the power consumption of AI tools may rival that of entire countries [11]. However, new types of data centre ("hyperscale" data centres) can improve energy efficiency [10].
Exploiting the efficiency enhancements offered by innovative technologies requires political will and the corresponding budgetary resources. Conversely, a lack of support, including financial, may inhibit technological development and hinder or prevent innovation [12].
In addition to expansion of a recycling and circular economy, lightweight construction can also help to raise energy efficiency, as the lower mass of lightweight products and vehicles results in less energy being consumed.
Finally, consumer behaviour is an important factor in efforts to save energy. Increased awareness of environmental protection and nature conservation can act as a driver; a greater need for energy in the economy as a whole owing to changes in demand, production and distribution structures can lead to efficiency improvements. Conversely, psychological and regulatory factors influencing individuals’ behaviour can prevent the anticipated efficiency potential being fully realized (rebound effect). Such an effect occurs when the increase in efficiency results in increased demand or use, thereby reducing the actual savings [13].