1. Federation of European Heating, Ventilation and Air-conditioning Associations Renewables in nZEB office and school buildings REHVA nZEB Task Force Jarek Kurnitski Professor, Vice-president REHVA Tallinn University of Technology Aalto University jarek.kurnitski@ttu.ee www.nzeb.ee February 27, 2015 Wels Martin.Thalfeldt@ttu.ee Estonia Jonas.Graslund@skanska.se Sweden Per.Kempe@projektengagemang.se Sweden Jeroen.Verwer@rhdhv.com Netherlands

2. Federation of European Heating, Ventilation and Air-conditioning Associations Introduction Energy from renewable sources, including energy from renewable sources produced on-site or nearby is one part of EPBD nZEB definition Therefore it should be possible to calculate RES contribution (called also RES share or RER – renewable energy ratio) Some countries have set requirements for RES share, some countries are not:

3. Federation of European Heating, Ventilation and Air-conditioning Associations nZEB buildings in this study LocationTypeDataHeatingCoolingRenewable FRA Dijon, France OfficeMeasuredBiofuel Free cooling + chiller PV SUIGland, SwitzerlandOfficeSimulatedGSHPBoreholesPV NL1 Hoofddrop, the Netherlands OfficeSimulatedGSHP BioCHP+SC FINHelsinki, FinlandOfficeSimulated District heat BoreholesPV NL2 Haarlem, the Netherlands Primary school Simulated, hourly GSHP PV+SC SWE1 Stockholm, Sweden Office Simulated, hourly District heat BoreholesWind SWE2 Helsingborg, Sweden Office Measured, hourly GSHPBoreholesPV ESTRakvere, EstoniaOffice Simulated, hourly District heat Open wellsPV

4. Federation of European Heating, Ventilation and Air-conditioning Associations Older nZEB case studies Buildings 1-4 are nZEB office buildings in France, Netherlands, Switzerland and Finland Reported in REHVA Journal (3/2011, 2/2012, 5/2012)

5. Federation of European Heating, Ventilation and Air-conditioning Associations nZEB Task Force buildings 4-8 analyzed in more detail

6. Federation of European Heating, Ventilation and Air-conditioning Associations RER calculation bases REHVA nZEB report and FprEN 15603:2014 define RER as complementary indicator (in addition to primary energy indicator) RER equation is based on the total primary energy, requiring “double“ set of primary energy factors: RER is calculated relative to all primary energy use in the building, including for instance ambient heat sources of heat pumps and free cooling but not including passive solar

7. Federation of European Heating, Ventilation and Air-conditioning Associations REHVA nZEB technical definition – 2013 revision ZEB, net ZEB, PEB and nZEB definitions A set of system boundaries to calculate: −Energy need −Energy use −Delivered and exported energy −Primary energy −Renewable energy ratio −Nearby energy production −Sites with multiple buildings Load matching and grid interactions Worked examples National low energy and nZEB requirements/targets from selected countries

8. Federation of European Heating, Ventilation and Air-conditioning Associations EP and RER system boundary System boundaries (SB) for energy need, energy use and delivered and exported energy calculation. The last one may be interpreted as the building site boundary. Demand reduction measures can be distinguished from RE solutions in the energy use SB, not in the delivered/exported energy SB Primary energy RER

9. Federation of European Heating, Ventilation and Air-conditioning Associations Biofuels in EP and RER calculation When on-site generation is directly deducted from energy use/delivered energy, biofuels are accounted with a primary energy factor, the same approach applies also for district heat In this study, energy policy (cost) factor of 0.5 is used for biofuel (used in some MS to ensure the effective use of biofuels as lower factor may lead to wasteful use of biomass) Biofuels are used in two buildings: –FRA has a biomass boiler for heating –NL1 has BioCHP for electricity and heat production (with biolone oil produced from slaughter house waste), resulting also in exported heat that is calculated with the same primary energy factor of 0.5

10. Federation of European Heating, Ventilation and Air-conditioning Associations Delivered, on-site and nearby generated, and primary energy FRASUINL1FINNL2SWE1SWE2EST Heating10,56,013,338,320,532,210,025,0 Cooling2,46,73,30,33,21,30,52,0 Fans & pumps6,58,117,59,411,813,23,09,7 Lighting3,716,321,112,5 16,512,611,3 Appliances21,226,819,219,35,016,912,618,5 On site electricity-15,6-30,9-73,8-7,1-36,5-39,0-19,6 Nearby electricity-47,9 BioCHP fuel 184 Exported heat-50,0 Primary energy 424266689633232361 Primary energy factors nrenrentot Biofuel0.50.50.50.51.0 District heat0.70.70.30.31.0 Electricity2.00.20.22.22.2

11. Federation of European Heating, Ventilation and Air-conditioning Associations 25.0 heating 12.3 cooling 11. lighting BUILDING TECHNICAL SYSTEMS 19.6 PV electricity, from which 12.5 is used in the building and 7.1 exported District heat 25.0 (30% renewable) Solar and internal heat gains/loads Heat transmission through the building envelope ENERGY NEED (56.1 kWh/(m 2 a)) DELIVERED ENERGY District heat 25.0/1.0 = 25.0 Free cooling 6.7/17.5 = 0.4 Compressor cooling 5.6/3.5 = 1.6 Lighting 11.3 Fans and pumps 9.7 Appliances 18.5 Primary energy: EXPORTED ENERGY System boundary of delivered and exported energy on site Delivered and exported energy on site Electricity 7.1 18.5 appliances (Sum of electricity 41.5) Solar panels Electricity 29.0 (20% renewable) Example (Rakvere, EST)

12. Federation of European Heating, Ventilation and Air-conditioning Associations 6.7+0.4 = 7.1 geothermal 19.6 PV electricity, from which 12.5 is used in the building and 7.1 exported SOLAR ENERGY Solar panels System boundary of renewable energy use Free cooling heat exchanger (connected to energy wells) GEOTHERMAL ENERGY Renewable energy ratio: BUILDING TECHNICAL SYSTEMS DELIVERED ENERGY District heat 25.0/1.0 = 25.0 Free cooling 6.1/17.5 = 0.3 Compressor cooling 5.6/3.5 = 1.6 Lighting 11.3 Fans and pumps 9.7 Appliances 18.5 EXPORTED ENERGY Electricity 7.1 (Sum of electricity 41.4) Electricity 28.9 (20% renewable) District heat 25.0 (30% renewable) Example (Rakvere, EST)

13. Federation of European Heating, Ventilation and Air-conditioning Associations RER-calculation options (Rakvere, EST) RERp – renewable energy ratio based on total and renewable primary energy factors RERd – renewable energy based on delivered energy RERnren – renewable energy based on non-renewable primary energy factors (not correct) RERp w/o export – RERp without exported electricity RERp w/o appliance – RERp without appliances REF – renewable electricity fraction index REM – percentage of produced renewable electricity that is utilized in the building

14. Federation of European Heating, Ventilation and Air-conditioning Associations RER – all buildings The effect of the use of primary energy factors, from top to down: Total and renewable primary energy factors (typically do not exist in MS) Without factors Non-renewable primary energy factors (not correct, but typically exist in MS)

15. Federation of European Heating, Ventilation and Air-conditioning Associations RER without export and appliances RER p without appliances can become negative (Helsingborg) because of exporting with factor 2.0 (i.e. dividing with negative value)

16. Federation of European Heating, Ventilation and Air-conditioning Associations REF & REM Stockholm with nearby wind shows somewhat different pattern: of percentage of produced renewable electricity that is utilized in the building REM of renewable electricity fraction REF

17. Federation of European Heating, Ventilation and Air-conditioning Associations RER indicator vs. primary energy Good (negative) correlation between primary energy and RER Not very technology dependent >100% RERp does not allow to draw conclusions on the grid load

18. Federation of European Heating, Ventilation and Air-conditioning Associations What additional information RER provides? RER is not very sensitive on the use of total/ren, or nren primary energy factors or calculation without factors Annual RER value does not allow to estimate the grid load W/m 2 delivered and exported electricity indicators (hourly values) provide more information HaarlemStockholmHelsingborgRakvere Max delivered, W/m 2 32,624,227,013,9 Max exported, W/m 2 -31,6-12,6-34,2-17,5 10th percentile, W/m 2 -3,8-6,2-6,5-2,7 90th percentile, W/m 2 15,010,914,88,4 Exported Delivered