1. Contract: EIE/07/069/SI2.466698 Duration: October 2007 – March 2010Version: January 18, 2010 A vehicle to energy-efficient lighting EN 15193: Energy performance of buildings – Energy lighting requirements Jan de Boer and Anna Staudt jdb@ibp.fhg.de, anna.staudt@ibp.fhg.de Fraunhofer Institute of Building Physics, Germany CENSE

2. slide 2 Outline The EU CENSE project Background and By-Products Scope of the Standard Principle of the Method Artificial Lighting Daylight Lighting Controls Benchmarking Software: Bringing the Standard into daily design practice Conclusion and Outlook

3. slide 3 The EU CENSE project (Oct. 2007 - March 2010) Aim of the project: To accelerate adoption and improved effectiveness of the EPBD related CEN- standards in the EU Member States These standards were successively published in the years 2007-2008 and are being implemented or planned to be implemented in many EU Member States. However, the full implementation is not a trivial task Main project activities: A.To widely communicate role, status and content of these standards; to provide guidance on the implementation B.To collect comments and good practice examples from Member States aiming to remove obstacles C.To prepare recommendations to CEN for a “second generation” of standards on the integrated energy performance of buildings

4. slide 4 Brief introduction A brief introduction to the CENSE project and the CEN-EPBD standards is provided in a separate presentation:

5. slide 5 More information More information and downloads: www.iee-cense.eu Disclaimer: CENSE has received funding from the Community’s Intelligent Energy Europe programme under the contract EIE/07/069/SI2.466698. The content of this presentation reflects the authors view. The author(s) and the European Commission are not liable for any use that may be made of the information contained therein. Moreover, because this is an interim result of the project: any conclusions are only preliminary and may change in the course of the project based on further feedback from the contributors, additional collected information and/or increased insight.

6. slide 6 Background and By-Products Background of the standard –Big energy-saving potential hidden in lighting –Consideration of energy-efficient lighting in standardisation Beneficial By-Products applying the standard –Authentic overall building energy balance –Methodology usable as Design Tool –Further optimizations in designing lighting systems –Promotion of the efficient use of daylight

7. slide 7 Scope of the Standard Providing a guiding framework The CEN standard outlines general aspects, leaving room for national variations and refinements using more detailed sub-models and methods. Evaluation of the lighting energy -The standard provides a calculation methodology, offering alternative routes to determine the energy use. (Illustration on the following slide) -The metering of the energy use is specified and a benchmarking system for different building types, allowing to rank calculated or measured lighting energy demands, is provided. Unlimited applicability The standard can be applied to existing buildings as well as for the design of new or renovated buildings.

8. slide 8 Alternative Routes The standard offers alternative routes to determine the lighting energy requirements.

9. slide 9 Principle of the Method Basis of the calculation method - Basic parameters of energy use: - the power of the lighting system [p] - the time, the system runs [t] -Obtaining the electric lighting energy consumed: - Precise: Integration of the power consumption p(t) over time - Simplified: Scaling the power with the effective time t eff (Illustration on slide 8) Main result Lighting energy demand of a building (zone) per square meter

10. slide 10 Principle of the Method Determination of the electric lighting energy consumption by: - Integration (blue area) - Multiplication (red area) j

11. slide 11 Artificial Lighting The standard’s main focus is on the assessment of installed power in existing buildings Calculation methods for new buildings are needed -No calculation approach in design stage -Simplified estimation methods would be helpful

12. slide 12 Daylight 3-step approach for determining the daylight supply

13. slide 13 Daylight – 3-step approach Step 1: Identification of the daylight penetration Depending on construction parameters of room and façade for example: - geometry - overhangs - obstructions Step 2: Evaluation of the façade’s properties - The façade system is evaluated by its light transmittance (corrected by: fenestration, dirt on glazing and oblique light incidence) - Sun-shading systems are not covered explicitly

14. slide 14 Daylight – 3-step approach Step 3: Determination of the “relative luminous exposure” Daylight factor, façade properties and relative luminous exposure are correlated This correlation is: - a measure of the daylight’s energy saving potential - performed for diffuse illumination only Result of all 3 steps: A daylight supply factor to calculate energy saving

15. slide 15 Daylight - Situation of Watford, UK Correlation of daylight penetration with climate and maintenance illuminance level

16. slide 16 Lighting Controls Consideration of Lighting Controls The standard accounts for the impact of lighting controls, allowing to calculate their impact on energy consumption. Regarding different controlling types -Occupation detection - Daylight-dependent lighting control

17. slide 17 Benchmarking Reference values for different building types Extract of the standard’s Annex F, Table F.1: Bench mark default values:

18. slide 18 Software - Bringing the standard into daily design practice Support of practical application Software implementing the CEN-standard is needed Existing Software Some tools already exist for calculating the lighting energy demand, e.g. “DIALUX” or “Relux” (Example Application, using “DIALUX” on following slide 18)

19. slide 19 Software - Example of Use: Design Software DIALUX A room with a single window is examined.

20. slide 20 Conclusion and Outlook Overview of the CEN standard: EN 15193 -The standard provides an useful umbrella framework, with a mandatory simple general calculation framework. -The appendix of EN 15193 recommends additional, more elaborated methods, which can also be applied, as well as methods of national level projects. Contents of the standard -Applying the computational methods of the standard for lighting in existing buildings, an energetic analysis and the optimization of lighting installations can be achieved. -The determination of the installed power in new buildings is not included. -In the calculation artificial lighting, daylight and lighting controls are integrated. Desirable Improvements in a future revision -Inclusion of a simple method for calculating the installed power for new buildings. -Reconsideration of the quite high benchmark values. -Inclusion of methods to rate and energetically optimize sun shading and glare protection systems.