1. Energy Efficiency - Made in Germany February 16 th, 2011 Exportinitiative Energy Efficiency in Dutch Greenhouse Industry Hans-Jürgen Tantau on behalf of the German Federal Ministry of Economics and Technology www.efficiency-from-germany.info The Low Energy Greenhouse - An Approach to Sustainability

2. Contents  Introduction: energy situation, global warming  Objectives  Research project “ZINEG”  Conclusions  Acknowledgements

3. Energy Efficiency - Made in Germany www.efficiency-from-germany.info Introduction

4. Introduction: Energy Situation (global)  Availability of oil and gas, peak production  2010  Fuel consumption is still increasing  Emission of (fossil) CO 2 is increasing the CO 2 -concentration  Global warming  Reduction of fossil CO 2 -emission

5. Energy Efficiency - Made in Germany www.efficiency-from-germany.info Objectives

6. Increase of energy efficiency in protected cultivation  Systematic approach  to reduce the energy consumption by 90 %  to operate a greenhouse  without fossil energy,  without fossil CO 2 -emissions  ZINEG, the Low Energy Greenhouse Objective

7. Energy Efficiency - Made in Germany www.efficiency-from-germany.info ZINEG, the Low Energy Greenhouse

8. ZINEG: A Joined Research Project Economics economic and ecological evaluation Hanover max thermal insulation, temperature integration Munich/ Neustadt a.d. Weinstraße neutral CO 2 -energy supply Berlin, Großbeeren, Potsdam-Bornim closed greenhouse Public relations Association for Technology and Structures in Agriculture (KTBL)

9. The Low Energy Greenhouse in Hannover Reduction of energy consumption using  new covering materials  triple thermal screens  solar energy by day and night storage  climate control strategies  energy optimized cultivation programs Maximum energy saving for the production of pot plants

10. New Covering Materials Requirements:  high light transmittance  good thermal insulation Technical solution:  double glazing with anti reflective coating, filled with Argon Problems: - increase of air humidity

11. Covering Material Spectral transmittance of GroGlass (single and double glazing) (high PAR and lower NIR transmittance) Source: v. Elsner, 2010 Float glass GroGlass single GroGlass double

12. Thermal Screen Requirements:  no light reduction during day time  no leakages, when closed Technical solution:  triple thermal screen different materials (aluminised, clear, black) Problems: - air humidity (control of thermal screen)

13. Thermal Screen

14. Use of Solar Energy Requirements:  expanded time for CO 2 -supply  crop orientated climate control strategies Technical solution:  ventilation as late as possible (CO 2 -supply)  low temperature heat exchanger  storage of solar energy in water tanks (day and night storage)

15. Yearly Solar Radiation and Heat Requirement Low Energy Greenhouse, location: Hanover (example),  i = 15 °C, double glazing, triple thermal screen solar radiation mean heat requirement

16. Use of Solar Energy by Day and Night Storage M warm water storage heat pump cold water storage greenhouse 1 greenhouse 2 heat exchanger condenser boiler heat exchanger M M M M M

17. Low Temperature Heat Exchanger inlet heat exchanger fan return 1.0 m 0.2 m Source: v. Elsner, 2009)

18. Heat Pump and Water Storage Heat pump (28 kW)  30 W/m 2 Warm and cold water storage (50 m 3 )

19. Climate Control Strategies Low energy greenhouse, Triple thermal screen, 80 % saving at night energy partition at day energy partition at night

20. Energy Efficiency - Made in Germany www.efficiency-from-germany.info Energy Saving Potential

21. Energy Saving Potential (values are examples) The technical realisation of the Low Energy Greenhouse is possible!

22. Conclusions The realisation of the Low Energy Greenhouse is a challenge!  an Approach to Sustainability Limitations:  crop response (humidity)  disease infections  plant nutrition (etc. Ca)  economical evaluation  ecological evaluation e.g. cumulative energy demand carbon footprint

23. ACKNOWLEDGEMENTS Project grant: Sponsored by the Federal Ministry for Environment, Nature Conservation and Nuclear Safety and the Rentenbank managed by the Federal Ministry of Food, Agriculture and Consumer Protection with assistance of the Federal Agency for Agriculture and Food.

24. Thank you very much for your attention! Further information: www.zineg.de