Energy Efficiency and Risk Management in Public Buildings (EnRiMa)
Starting point / motivation
On average, one-third of Europe's use of energy is required to supply the energy demand in buildings. Annual energy demand in households and services is expected to rise from currently 32.5 PWh to 39.3 PWh in 2030. With the adoption and implementation of directive 2010/31/EU on the energy performance of buildings, the European Union (EU) attempts to initiate a counter-trend. The goal is to reduce conventional energy consumption by reducing energy demand itself and by increasing the use of renewable energy sources.
Content and objective
The overall objective of EnRiMa was to develop a decision-support system (DSS) for operators of public buildings. By providing integrated management of conflicting goals such as cost minimisation, meeting energy demand, efficiency, and emission-reduction requirements as well as risk management, the DSS enables operators to improve building energy efficiency in the most cost-effective manner based on their tolerances for comfort and risk.
The DSS enables long-term planning aimed at increasing energy efficiency, specifically analyses of retrofits and/or expansion of on-site energy sub-systems, in order to meet forthcoming EU targets for reducing CO2 emissions.
Following technologies are considered:
- passive building measures as highly insulating windows and building shells
- solar thermal
- electric and thermal storage
- fuel cells and other decentralized combined heat and power (CHP)
EnRiMa can also be extended by new technologies. Furthermore, the EnRiMa DSS enables preventive building operation based on weather forecasts to save energy.
After a careful analysis of the existing energy systems at four sites in Austria and Spain the DSS was designed. A laboratory facility in Bizkaia, Spain served for laboratory testing of the DSS, while a community centre in Siero, northern Spain and the University of Applied Science Burgenland, Campus Pinkafeld represented the venues for the real-world validation exercise. Due to the state-of the art data collection system at ENERGYbase in Austria it was used for the EnRiMa DSS calibration. Energy flows, so called Sankey diagrams, for ENERGYbase can be found at www.cet.or.at/enrima/sankey_en.php.
Both an Operational DSS and a Strategic DSS were developed within the EnRiMa project. The Operational DSS optimizes the building operation for the next day. Within this optimization, the desired user comfort is the observed quality criterion.
The Operational DSS can be used in combination with existing building energy management systems (EMS), e.g. DESIGOTM from Siemens. EnRiMa collects data from the EMS, analysis it, collects weather forecasts from the internet for operations optimization, and combines all that data and performs the optimization on the EnRiMa web-server. The results will be sent to the building operator, decision maker, and the EMS for possible technology dispatch. This approach enables this new kind of optimization without the need of EMS upgrades.
The Strategic DSS works with a stochastic optimization model which determines feasible investment decisions for a given building. It considers cost reduction, CO2-emission reduction and energy consumption reduction. Uncertainty in the energy price trend is also considered in the Strategic DSS.
Results / conclusions
The savings based on the Operational DSS were measured by independent energy auditors. The implementation of the Operational DSS at Campus Pinkafeld resulted in average energy savings of 8 % compared to business as usual days were the Operational DSS had no influence on the building operation. Savings up to 16 % were possible at some days at Campus Pinkafeld. No additional technology was added to achieve these results. The Strategic audit at the community center in Siero, Spain, performed by the Spanish project partner and Applus Norcontrol, S.L.U., identified CO2-reduction potentials up to 17 %.
University College London (UCL), United Kingdom
Project or cooperation partners
- Stockholms Universitet (SU), Schweden
- International Institute for Applied Systems Analysis (IIASA), Österreich
- Universidad Rey Juan Carlos (URJC), Spanien
- Zentrum für Energie und innovative Technologien (CET), Österreich
- Minerva Consulting & Communication (MCC), Belgien
- Stiftelson SINTEF, Norwegen
- Fundacion Labein Tecnalia-Lab (TECNALIA), Spanien
- Hidrocantabrico Energia S.A. (HCE), Spanien