Seit über einem Jahrzehnt entwickeln europäische Kommunen Initiativen, Strategien und Aktionspläne, um die Energieeffizienz privater und kommunaler Infrastrukturen zu steigern. Die Kommunen der EU-Mitgliedstaaten müssen gemäß der EU-Richtlinie zur Energieeffizienz zusammenarbeiten, um sicherzustellen, dass bis 2020 eine Energieeffizienz von 20 % und bis 2030 eine Energieeffizienz von 32,5 % erreicht wird.
Es wurden Initiativen wie der Konvent der Bürgermeister ins Leben gerufen, um das Engagement für Energie- und Klimaziele zu fördern. Die Unterzeichner haben sich freiwillig verpflichtet, die Energieeffizienz und die Nutzung erneuerbarer Energiequellen zu steigern. Um dies zu erreichen, haben die teilnehmenden Kommunen einen Nachhaltigkeits-Energie-Aktionsplan (SEAP) ausgearbeitet und vorgelegt, in dem sie ihre Energiespar- und Klimamaßnahmen festlegen. Seit 2008 haben mehr als 6000 Kommunen einen SEAP entwickelt und genehmigt; im Vergleich zur Gesamtzahl der Kommunen in ganz Europa liegt jedoch noch ein weiter Weg vor ihnen.
Es wurde festgestellt, dass der Gebäudebestand einer Kommune das größte Einzelpotenzial für Energieeinsparungen darstellt. Außerdem wird erwartet, dass bis 2050 mehr als zwei Drittel der Weltbevölkerung in städtischen Gebieten leben werden. Daher zielt diese Lösung darauf ab, die Konzeption und Umsetzung von kommunalen Energiesparmaßnahmen zu erleichtern.
Zu lösende Probleme
Verbrauch fossiler Brennstoffe
Beeinträchtigung der städtischen Luftqualität
Local authorities may be tempted to opt for projects improving energy efficiency with short paybacks. However, this approach will not capture the majority of potential savings available through energy retrofits. Instead, it is recommended that all profitable options are included, especially those which yield a rate of return higher than the interest rate of the investment capital. This approach will translate into greater savings over the long term. Too often, quick paybacks on investments mean that organisations do not pay attention to "lifecycle costing".
Life cycle costs are the total cost of ownership over the life of an energy saving system, such as: planning, design, construction and acquisition, operations, maintenance, renewal and rehabilitation, depreciation and cost of finance and replacement or disposal. Payback time should be compared with the lifespan of the goods to be financed. For instance, a 15-year payback time should not be considered as a long period of time when it comes to building with a lifespan of 50-60 years.
Efficiency Performance Contracting (EPC) (ClimACT, 2017)
An energy performance-based business model proposes a partnership between customers and Energy Servicing Companies (ESCOs) to develop energy saving measures. EPC’s can be executed in two forms: through shared-savings, or through a guaranteed-savings scheme. In a shared-savings EPS, an ESCO is remunerated based on the project’s generated energy saving and the fee paid by the customer reimburses the capital costs of the project. In a guaranteed savings EPC, the ESCO takes on a technical risk, by guaranteeing a saving percentage on the customers energy bill. If the agreed savings are not achieved, the ESCO is required to reimburse the customer the difference between the actual savings and the agreed upon savings. The customer finances the measure completely, relying on the performance promised by the ESCO.
An EPC is well suited for large scale projects, especially in the public sector, because of high transaction costs and long payback times. Usually, the private sector is less attracted to contracts with long payback times.This means that, in order to establish a contract in the private sector, ESCOs should focus on the implementation of ECMs with rapid return of investment. Difficulties to set up an energy baseline make it harder for the ESCO to predict energy savings and the measurement and verification process needed to follow up on the project results can be costly (Warget, 2011).
Build-Own-Operate-Transfer (BOOT) (ClimACT, 2017)
In the Build-Own-Operate-Transfer (BOOT) business model, the ESCO has complete control of the energy saving measure. They build, deploy, and operate the project through a given contracted period of time. At the end of the contract, the ESCO transfers the installation/system to the customer.
During the contracted period of time, the ESCO is in control of the energy saving measure and a fee is charged to the customer for the service delivered. This way, the ESCO investment and operational costs are covered by the fees. The BOOT model is similar to a loan made by the ESCO to the costumer, which also includes energy management during the contract period.
Chauffage (EU JRC, 2021)
In a Chauffage Business Model, the ESCO takes over complete responsibility for providing the energy services (e.g. space heat, lighting, motive power, etc.) to the customer. As a form of outsourcing energy management, Chauffage is typically used in municipalities where the energy supply market is competitive.
The ESCO assumes the responsibility for providing the agreed energy service for a cost lower than the previous service or for a more efficient service for the same cost. The more efficient and cost-effective it can supply energy, the greater earnings the ESCO will have. Chauffage contracts give the strongest incentive to ESCOs to provide services in an efficient way. The fee paid by the municipality under a Chauffage arrangement is calculated on the basis of its existing energy bill minus a percentage saving (often in the range of 5-10%). Thus, the municipality is guaranteed an immediate saving relative to its current bill.
Chauffage contracts are typically quite long (20-30 years) and the ESCO provides all the associated maintenance and operation during the contract. Chauffage contracts are very useful whenere the customer wants to outsource facility services and investment.
Stakeholder Map for a municipal energy saving system (BABLE, 2021)
The United Nations Economic Commission for Europe (UNECE, 2020) has listed seven recommendations to implement and adopt energy savings systems:
- Continue harmonisation of building energy codes by ensuring comprehensive coverage of all types of buildings.
- Define national energy efficiency target, which is to be based on primary (or final) energy consumption, primary (or final) energy savings, or on energy intensity.
- Continue strengthening requirements for insulation, ventilation and technical installations.
- Give more attention to the airtightness of the building envelope
- Ensure building codes include requirements for air conditioning, lighting, use of renewable energy sources, and natural lighting
- Make mandatory requirement for inspection of boilers and air-conditioning systems to improve quality and precision of energy performance certification in multi-family buildings
- Follow a holistic approach in building energy codes based on building energy performance requirements (heat, ventilation, air conditioning, lighting, etc.)
- Introduce or strengthen quality assurance measures, especially during the early stage of energy performance certification.
- Requirements for certifying experts should be harmonised
- Certifier needs to be physically present on-site
- Quality check procedure of energy performance certification should be harmonised
- Development of centralised energy performance certification databases and digitalisation of certification process
- Challenges of infrastructure energy performance data collection on energy use and the existing gaps should be priority areas for research.
- Establish or strengthen proper electronic monitoring system of compliance, enforcement and quality control processes to ensure compliance with international building energy codes and standards.
- Define measures to ensure that materials and products used in construction are subject to rigorous quality control to meet energy efficiency requirements, to maintain resistance of buildings to local environmental loads, and to ensure they do not threaten safety of people and property.