Commissioning ground coupled heat pump office building Bayer Diegem VCB Hernieuwbare energie voor gebouwen, 2012-09-13 ir. Pedro Pattijn
Agenda 1. Bayer office building project 2. Evaluation Energyconsumption Heat pumps Free-cooling Bore hole system Comfort 3. Primary energysaving & CO2-reduction 4. Conclusions & Proposals
Agenda 1. Bayer office building project 2. Evaluation Energyconsumption Heat pumps Free-cooling Bore hole system Comfort 3. Primary energysaving & CO2-reduction 4. Conclusions & Proposals
Building Architect : Reginald Schellen Building type: Office building Design : 2007 Construction: 2008 2009 In use : feb 2009 Net floor area (NFA): 11.249 m² Conditioned floor area: 7.050 m² Demo-project innovative energytechnologies VEA Green Building European Commission Belgian Energy Award non-residential buildings 2009
Building
Building
Installation Geothermal system: Backup heating system: Backup cooling system: Distribution system: Other systems: borehole heat exchanger (60 probes, length 100m) used for heating and cooling purposes gas condensation boiler compression chiller TABS, floor ventiloconvectors, ventilation Earth-air heat exchanger (EAHX) (12 tubes, diam. 315 mm, length 55 m) thermal heat recovery wheel
System
System Source : Geotabs Tetra project
Scheme Source : Geotabs Tetra project
Metering
Borehole heat exchanger 60 bore holes (5 x 12, rectangular) 100m depth 4m distance 50 m³/h
Heat Pump Standard HP1&HP2 : Lennox HWW 070CS, 70 kw th, 16 kw el, (COP=4,5) Ground : in 6 C / out 3 C Condensor : in 23 C / out 28 C HP3 : Lennox HWW 055CS, 51 kw th,16 kw el, (COP=3,2) Ground : in 6 C out 3 C Condensor : in 40 C / out 45 C Plate heat exchanger free cooling, 170 kw Backup Boiler: Viessmann Vitocrossal 300 CT3, 2x383 kw, regime 70/50 C, eff. 109% Chiller : Lennox NAC 420D NM1M, 430 kw th, (EER 3,11), R410A, chilled water 12/7 C outside air temperature 35 C
Agenda 1. Bayer office building project 2. Evaluation / Commissioning Energyconsumption Heat pumps Free-cooling Bore hole system Comfort 3. Primary energysaving & CO2-reduction 4. Conclusions & Proposals
Year Consumption Specific Gas consumption (kwh/m².year) Specific Electrical consumption (kwh/m².year) Bayer < > Senter Novem 2007 500 10.000m² offices Energy Consumption Benchmarks Air conditioned - standard offices Ingenium average offices 70 151 178 100 120 85 226 60 Considerations : No submetering (gas, heat, cold, electrical) High comfort requirements summer & winter High occupancy rate
Gas consumption Considerations : Considerable high consumption at summer : kitchen (sanitary hot water) Humidification : steam for AHU May / june 2010 : problem with humidification
Electrical consumption Considerations : High consumption : AHU, office equipment, lights, kitchen equipment Small consumption: 3 heat pumps, chiller Small reduction in monthly electricity consumption (i.e. water pump fountain)
Electrical consumption Considerations : Total low electricity consumption HPs HP3 : almost no elec. consumption HP1 & HP2 : similar profile Summer : (almost) no consumption More heating power available Proposals : Connect HP3 to central heat system Change climate control strategy
Temp.set point Temperatures HP
Energyperformance HP P therm,deliv P therm,extract P electrical COP year COP std.ref. (MWh/year) (MWh/year) (MWh/year) HP 1+HP2 78 65 17 4,6 4,5 HP3 29 3 26 1,3 3,2 HP 1+ HP2 HP3 P th,deliv P th,extract P el COP P th,deliv P th,extract P el COP MWh MWh MWh MWh MWh MWh nov '10 (*) 12,16 10,00 2,16 5,63 2,51 0,44 2,07 1,21 dec '10 25,08 19,03 6,06 4,14 10,69 0,53 10,16 1,05 jan '11 15,65 12,21 3,45 4,54 5,21 0,55 4,67 1,12 febr '11 (*) 15,57 12,12 3,45 4,51 5,67 0,51 5,17 1,10 mrt '11 (*) 8,65 6,79 1,85 4,66 4,16 0,53 3,63 1,14 april '11 0,00 0,99 0,00 0,26 mei '11 0,00 0,00 0,00 0,04 juni '11 0,00 0,00 0,00 0,01 juli '11 0,00 0,00 0,04 0,03 0,01 0,03 1,25 aug '11 0,00 0,00 0,04 0,07 0,04 0,03 2,59 sept '11 0,00 0,00 0,04 0,03 0,00 0,03 1,17 okt '11 0,72 0,54 0,17 4,13 0,19 0,17 0,02 nov '11 1,30 1,04 0,27 4,88 0,44 0,44 0,00 dec '11 5,62 4,12 1,50 3,74 0,39 0,38 0,01 Considerations : COP HP3 very low! Proposals : Check HP3 Connect HP3 on central heating system
Energyperformance HP Considerations : HP1 & HP2 = alternating regime Pel HP 1 Pel HP 2 Pth HP 1 > Pth HP 2 COP HP1 = 5 COP HP2 = 3,5 Proposal : Check HP2
Free-cooling Considerations : Good operation free-cooling Small or no operation chiller Temperature diff. (depart/retour) is rather small More cooling power available Proposals : Change climate control strategy
Energy Balance Extracted heat : 64,4 MWh Extracted cold : 63 MWh Considerations : +/- good balance good regeneration Year over year temperatures / Long term balance = not enough info yet = to be followed up
Temperature bore holes
Thermal Comfort 23,5 20,5 Considerations: Design comfort criteria : 20 C 25 C = OK Optimal comfort zone : 20,5 C 23,5 C = +/- OK
Thermal comfort Considerations: Good thermal summer comfort Proposal : Increase temp. set.point / dead band temp. control in summer > energy saving
Thermal comfort Considerations : Winter comfort = OK Large spread oper.int.temp.(tmin Tmax) at similar Tref.ext. (range 0 C-10 C) Mid season = risk of overheating Control sunshades!
Agenda 1. Bayer office building project 2. Evaluation Energyconsumption Heat pumps Free-cooling Bore hole system Comfort 3. Primary energysaving & CO2-reduction 4. Conclusions & Proposals
Energy/CO2 saving Primary Energy Saving HPs + bore holes + backup boiler + backup chiller (Bayer) std. boilers + std. chillers (Reference) Electrical consumption MWh e 73 84 Primary electrical consumption GJ p 656 756 Gas consumption GJ p 0 302 Total Primary energy consumption GJ p 656 1.058 Reduction Primary energy GJ p 402 % Saving - 38% CO 2 -Saving HPs + bore holes + backup boiler + backup chiller (Bayer) std. boilers + std. chillers (Reference) CO2 due to electrical consumption ton 73 84 CO2 due to gas consumption ton 0 17 Total CO2-emission ton 73 101 Reduction CO 2 -emission % Saving - ton 28 28%
Agenda 1. Bayer office building project 2. Evaluation Energyconsumption Heat pumps Free-cooling Bore hole system Comfort 3. Primary energysaving & CO2-reduction 4. Conclusions & Proposals
Conclusions Evaluation 1. Energyconsumption: Gas: medium/low, no submetering Electricity: medium/high, heat pumps/chiller 2. Heat pumps COP HP1 > COP HP2 COP HP3 very low 3. Free-cooling: good performance 4. Bore holes : temperatures depart/retour = OK, good energy balance/regeneration 5. Thermal comfort : Good summer / winter comfort Risk of overheating in mid season (sunshades!)
HP 3: Check performance Connect to central heat system HP 1 / HP 2: HP1 = standard / HP 2 = backup Check performance HP2 Indoor climate control : Proposals Increase set.point / dead band zone indoor temperature within adaptive comfort limits Check controlstrategy individual roomcontrol of indoor temperature (TABS, ventilation, ventiloconvectors)
Towards optimal design and control of geothermal heat pumps combined with thermally activated building systems in offices GeoTabs www.geotabs.eu WP1: Project coordination and management WP2: State-of-the-art review of design methods design tree WP3: Inventory of cases online database WP4: Monitoring of real GEO-HP-TABS cases WP5: Model simulations WP6: System operation and controller development MPC implementation WP7: Comfort survey tool development www.comfortmeter.eu WP8: Guidelines for improved design and control REHVA guidebook WP9: Dissemination and valorisation
Questions? Ingenium nv ir. Pedro Pattijn Business Unit Manager Energy & Sustainability Nieuwe Sint Annadreef 23 8200 Brugge Tel. 050/40.45.30 Fax 050/40.45.34 E-mail: pedro.pattijn@ingenium.be Web: www.ingenium.be