Prepared by Valerie Hovland, ,

Size: px

Start display at page:

Download "Prepared by Valerie Hovland, ,"

Bethany Gordon
5 years ago
Views:

2 Prepared by Valerie Hovland, 303-275-4489, valerie_hovland@nrel.

1 2 Prepared by Valerie Hovland, , February 10, 2003 Rob Farrington (National Renewable Energy Laboratory), Patrick Coroller (ADEME), Carlo-Andrea Malvicino (Centro Ricerche Fiat), Raymond Gense (TNO), Denis Clodic (Ecole des Mines), Predrag Hrnjak (SAE/University of Illinois Mobile AC System Cooperative Research Program), Prof. Kruse (University of Hannover), Robert Mager (BMW), Shane Harte (Visteon)

2 27 billion liters (7.1 billion gallons) used for air conditioning annually Equivalent to 6% of the national fuel use, or 10% of the imported crude oil! Millions of Gallons Used for AC per Year

3 Metabolic Heat Generation 150 Watts th

4 Outline Important parameters impacting MAC fuel use & CO 2 emissions Modeling approach Modeling results Solutions to reduce MAC fuel use & CO 2 emissions

Important Parameters for AC Fuel Use Vehicle Design Vehicle Use 100 CYC_FTP Speed (km/h) 50 0 0 500 1000 1500 2000 2500 Time (sec) Environ- ment

5 Important Parameters for AC Fuel Use Vehicle Design Vehicle Use 100 CYC_FTP Speed (km/h) Time (sec) Environ- ment Month Dec 5 Nov Temp (C) Oct Sept 30 Aug July June 20 May Apr 25 Mar 5 15 Feb 10 5 Jan 12-6am 9am-1pm 4-7pm Time of Day 10pm-12am

6 Factors Impacting MACS Fuel Consumption and Associated CO 2 Emissions Vehicle Design Style Thermal AC System Glazing Area Slope Vehicle mass Cabin size and mass Instrument panel size Engine type, displacement Frontal area and geometry Vehicle exterior/interior color Vehicle drag, rolling resistance Optical Properties Cabin Paint Glass Instrument Panel Mass Insulation Air leakage Thermal properties Parked Car Ventilation Controls Cabin temp Recirculation Compressor Solar compensation Exhausters Air distribution System weight Refrigerant type Compressor Fixed displacement Variable displacement

7 Factors Impacting MACS Fuel Consumption and Associated CO 2 Emissions Vehicle Use Driver/Occupant Driving style Vehicle maintenance Windows open/closed Interface with A/C Control A/C use Comfort Defogging/dehumidification Noise/allergen reduction Pollution/dust reduction Drive Cycle Regulatory Real world City vs. Highway Idle time (engine off/on) Vehicle speed impacts Engine speed Condenser airflow Cabin heat loss/gain In sun In shade Parked Vehicle orientation Sunroof closed/open Windows closed/open

8 Factors Impacting MACS Fuel Consumption and Associated CO 2 Emissions Environment Wind Climatic Humidity Solar radiation Air temperature Air density (altitude) Thermal Comfort Perspiration Cabin humidity Cabin temperature Air velocity on body Thermal asymmetry Solar radiation on body Mean radiant temperature Thermal comfort model (Fanger) Metabolic rate Occupant Recent environment Occupant preferences Clothing type and level Heat/moisture transfer Thermal capacitance Moisture capacitance

9 Time Distance Max Spd Avg Spd Idle TimeMax Accel Drive Cycle sec km km/h km/h sec m/s^2 US SC FTP NEDC (Urban + ExtraUrban) J U.S. SFTP test procedure now includes AC operation for regulated emissions only (SC03) Many other drive cycles Speed (km/h) CYC_FTP Time (sec)

10 Fuel and CO 2 Impacts of Using AC Vehicle: 180 g CO2/km (7.7 liters/100km, 30.4 mpg) FTP US06 SC03 NEDC J-1015 Range Fixed Disp 125% 112% 124% 126% 130% % Variable Disp 116% 107% 116% 116% 119% % Fixed - Variable 9% 5% 9% 10% 10% 5-10% For example, SC03 drive cycle used in U.S. SFTP shows 24% and 16% over-consumption for fixed and variable displacement compressors

11 Modeled Fuel Impacts of Using AC Experimental Fuel Impacts (5 vehicles, 28C, 50% RH) Centro Ricerche Fiat 7 30% 32 51%

12 MAC Fuel Consumption Varies with Climate Compressor power consumption varies with strongly with climate, vehicle speed, engine speed, blower speed, recirculation Forrest, Delphi, SAE % variation with climate AC usage varies with thermal comfort 100 AC load is a function of cabin soak temperature and demisting needs Percent AC Usage Cool Warm AC Usage Slightly Warm Thermal Sensation Vote Warm Hot

13 When are people thermally uncomfortable? Environmental Variables (T air, Humidity, Q solar ; t) Parked Car (M.R.T.) Sun or Shade Predicted Percent Dissatisfied Any Time of Day or Year Occupant Variables Clothing, Metabolic Rate

14 Predicted Percent Dissatisfied Any Time of Day or Year Time-of-Day and Time-of- Year Travel X = % of Time AC on for Each City % of Time AC on X Annual Distance Traveled = Vehicle Distance Traveled with A/C

15 Vehicle Distance Traveled with A/C Vehicle Fuel Economy with A/C Vehicle Fuel Economy if no A/C Vehicle Fuel Used with A/C Vehicle Fuel Used if no A/C Vehicle Fuel Used with A/C Vehicle Fuel Used if no A/C Vehicle Fuel Used for A/C Weight City Results by Population and Use Country Vehicle Registrations to Get Fuel Used for AC by Country

16 Norway Finland Sweden Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania Bulgaria Italy Greece Portugal Spain Turkey Austria Belgium Bulgaria Czech Republic Denmark Finland France Germany Greece Hungary Ireland Italy Netherlands Norway Poland Portugal Romania Spain Sweden Switzerland Turkey United Kingdom

17 Country Austria Belgium Bulgaria Switzerland Czech Republic Germany Denmark Spain City Graz Innsbruck Linz Salzburg Vienna Brussels Plovdiv Sofia Varna Geneva Ostrava Prague Berlin Bremen Dusseldorf Frankfurt Hamburg Koln Mannheim Munich Stuttgart Copenhagen Barcelona Madrid Palma Santander Sevilla Valencia Country City Finland Helsinki Tampere France Bordeaux Brest Clermont Dijon Lyon Marseille Montpellier Nancy Nantes Nice Paris Strasbourg United Kingdom Aberdeen Belfast Birmingham London Greece Andravida Athens Thessaloniki Hungary Debrecen Szombathely Ireland Birr Dublin Kilkenny Country Italy Netherlands Norway Poland City Brindisi Genova Messina Milan Naples Palermo Pisa Rome Torino Venice Amsterdam Groningen Bergen Oslo Kolobrzeg Krakow Poznan Warsaw Country City Portugal Braganca Coimbra Evora Faro Porto Romania Bucharest Clujnapoca Constanta Craiova Galati Timisoara Sweden Goteborg Karlstad Kiruna Ostersund Stockholm Turkey Ankara Istanbul Izmir

18 Temperature, humidity, solar radiation Dec Nov Oct Sept Temperatures (C) in Brussels 5 10 Aug July June May Apr Mar Feb Jan Hour of Day Source: Department of Energy Energy Plus TMY Calculations

19 Temperature, humidity, solar radiation Dec Nov Oct Sept Aug 85 Relative Humidity (%) in Brussels, BEL Month July June May Apr Mar Feb Jan Time of Day Source: Department of Energy Energy Plus TMY Calculations

20 Inputs Air Temperature (from data) Mean Radiant Temperature (from model & data) Humidity Ratio (from data) Air Velocity (assume 0.1 m/s) Activity (met) (1.5 met driving) Clothing (clo) (assume 0.6 clo: trousers, long- sleeve shirt) Thermal Comfort Model Energy Balance: Internal heat production Water vapor diffusion through skin heat loss Sweating heat loss Respiration latent and dry heat loss Convection heat loss Radiation heat loss Outputs Predicted Mean Vote (PMV) Predicted Percent Dissatisfied (PPD) Source: International Standards Organization (ISO) 7730 Moderate thermal environments Determination of the PMV and PPD indices and specification of the conditions for thermal comfort

21 Fanger s thermal comfort model excludes: Sun hitting a driver Thermal asymmetry Sitting on a hot seat High humidity impacts Model excludes AC use due to Automatic Temperature Control Windows closed for noise, dust, allergen, or pollution reduction Cabin soak temperature may be higher than modeled

22 MRT(time) = 20 C * NormalizedRadiation(t) * AvgRad / 4713Wh/m 2 60 Explorer Soak, 11/12/00 IP 50 Windshield Temperature (C) Headliner Seat Model 10 Ambient 0 0:00 6:00 12:00 18:00 0:00 Time from Midnight

23 Dec 5 Nov Mean Radiant Temperature (C) in Brussels, BEL Oct Sept 30 Aug 40 Month July June May Apr 25 Mar Feb 5 10 Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Time of Day 15 5

24 Predicted AC Usage for Cooling in Brussels Dec Nov Oct Predicted Percent Dissatisfied (%) in Brussels, BEL Clothing: 0.6, Velocity: 0.1, MRT: Ambient+Rise Sept Month Aug July June May 10 Apr Mar Feb Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Time of Day

25 Assume same travel patterns as U.S. Source: 1995 National Personal Transportation Survey 70% Daily Travel 25 Percentage of Travel Occurring during that Time am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Hour of the Day Percentage of Travel Occurring in that Month Average Summer Months: May - September Month of the Year

26 Norway Finland Percent of Time AC is in Use Sweden 3.4 to to 11.4 Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania 11.4 to to to to to to to 42.0 Italy Bulgaria Portugal Spain Greece Turkey

27 Norway Finland Percent of Time AC is Used for Dehumidification AC used for dehumidification if: Temperature C (35-55 F) Relative Humidity > 80% Sweden 3.8 to to 8.6 Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania Bulgaria Italy Greece Portugal Turkey 8.6 to to to to to to to 47.9 Month Dec Nov Oct Sept Aug July June May Apr Mar Feb Dehumidification Percent Usage in Brussels, BEL Dehumidification Usage No Dehumidification Usage Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm10pm-12am Time of Day Spain

28 Norway Finland Percent of Time AC is Used for Cooling and Dehumidification Centro Ricerche Fiat Sweden 19.4 to 28.6 Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania Bulgaria Italy Greece Portugal Turkey 28.6 to to to to to to to to 58.8 Comparison to Centro Ricerche Fiat s estimation: we may under predict usage Centro This study Recerche Fiat North Italy 41.7% South Italy 64.4% Avg Italy Cooling 35.7% 53.0% Cooling + Dehumid 44.2% Spain

29 Norway Vehicle Registrations (1000's) Finland 1323 to 2121 Sweden Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic 2121 to to to to to to to Sources: 2002 World Road Statistics from the International Road Federation ACEA European Automobile Manufacturers Association EA/Car_Parc_ pdf Portugal Austria Switzerland Hungary France Romania Bulgaria Italy Greece Turkey to to Million Total Vehicles EU Japan 62.4 Spain

30 Enough to Circle the Globe ~25 Times

31 Sweden Norway Finland Vehicle Kilometers Traveled Sources: 2002 World Road Statistics from the International Road Federation International Road Traffic and Accident Database Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania 6500 to to to to to to Italy Bulgaria Portugal Spain Greece Turkey

equivalent fuel consumption Torque (Nm) 350 300 250 200 150 Engine Efficiency

32 Vehicle Modeling in ADVISOR Using a Mercedes 1.7 liter compression ignition diesel Fuel economy expressed in gasoline equivalent fuel consumption Torque (Nm) Engine Efficiency Mercedes 1.7L Diesel Engine f/ ORNL Speed (rpm)

100-200 g CO 2 /km corresponds to 4.3-8.6 liters/100km 55-27 mpg Modeled 180 g CO 2 /km vehicle (2000) 7.7 liters/100km, 30.4 mpg on FTP cycle, hot initial conditions Vehicle parameters Cd*A = 0.

33 g CO 2 /km corresponds to liters/100km mpg Modeled 180 g CO 2 /km vehicle (2000) 7.7 liters/100km, 30.4 mpg on FTP cycle, hot initial conditions Vehicle parameters Cd*A = 0.33*2 m 2 Vehicle mass = 1220 kg, includes mass of AC system Engine max power = 91 kw Engine max efficiency = 36% Other parameters use ADVISOR defaults CO 2 emissions determined from fuel consumption 2.33 kg CO 2 /liter fuel

34 AC Modeling AC system: 125 cc variable displacement, HFC-134a Power consumption based on Delphi compressor curves 3-4 kw th cooling 125 cc displacement piston Scale fixed disp power consumption of Delphi curves by 125/210 and COP ratios Total power = P compressor /0.85 AC power (kw) System Power Consumption (kw) Fixed Disp Baseline: 125cc Compressor Speed (rpm) US Fixed Disp Variable Disp Defrost Mode Time (sec)

35 AC Power Consumption Modeling, cont. AC system Assume 32 C, 50% RH Defrost mode: 16 C, 80% RH Engine speed/compressor speed ratio = 0.64 [Forrest, Delphi] Month Temperature (C) in Madrid, ESP Dec 5 Nov 10 Oct 15 Sept Aug 30 July June May 10 Apr Mar 5 Feb 5 Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Time of Day Month Dec Nov Oct Sept Aug 50 July 65 June 70 May Apr 85 Relative Humidity (%) in Madrid, ESP Mar 55 Feb Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Time of Day Month Mean Radiant Temperature (C) in Madrid, ESP Dec Nov 10 Oct Sept Aug July June May Apr 10 Mar Feb Jan 12-6am 6-9am 9am-1pm 1-4pm 4-7pm 7-10pm 10pm-12am Time of Day

36 Norway Finland Million LitersTotal Fuel Consumed Totals Billion Liters Total Billion kg CO2 Total EU Japan Sweden 1264 to 1959 Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania Bulgaria Italy Greece Portugal Spain Turkey 1959 to to to to to to to to to to to Million Kilograms Total CO2 Emitted 2946 to to to to to to to to to to to to

37 25% Market Penetration of AC Systems Norway Finland Million Liters Fuel for AC Million Kilograms CO2 for AC Sweden 3 to to 13 7 to to 31 Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania 13 to to to to to to to to to to to to to to 635 Italy Bulgaria 273 to to to to 878 Portugal Greece Turkey 377 to to 878 Spain Totals, 25% Market Billion Liters for AC Billion kg CO2 EU % of Tota l 0.81%

38 100% Market Penetration of AC Systems Sweden Norway Finland Million Liters Fuel for AC 11 to 45 Totals, 100% Market Billion Liters for AC Billion kg CO2 EU % of Total 3.25% Japan % of Total 4.57% Denmark United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania Bulgaria Italy Greece Portugal Spain Turkey 45 to to to to to to to to to to to 1507 Million Kilograms CO2 for AC 26 to to to to to to to to to to to to 3510

39 Fuel Consumption of MACs for Demisting Totals, EU Billion Liters for Demist Billion kg CO2 Percent of Total 25% Market % 100% Market % AC used for demist if: Temperature C (35-55 F) Relative Humidity > 80%

40 Norway Finland Percent of Time AC is Used for Cooling and Dehumidification Sweden 19.4 to 28.6 United Kingdom Denmark 28.6 to to to 41.5 Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania 41.5 to to to to to 58.8 Italy Bulgaria Portugal Spain Greece Turkey

41 for Cooling and Demisting Totals Dehumid + Cooling, EU Percent of Total Consumption Billion Liters Billion kg CO2 25% Market % 100% Market %

compared with stock windshield [Farrington, NREL] Increase cabin thermal insulation Ventilation

42 Reduce the load (e.g. cabin soak temperature) Infrared reflective glazings Cabin soak temperature reduced up to 9 C compared with stock windshield [Farrington, NREL] Increase cabin thermal insulation Ventilation using a 50 W blower lowered temp 16 C [Atkinson, SAE ] Reflective body material Reduce glazing and IP areas Improve distribution of cooling (e.g. direct occupant cooling)

43 More efficient equipment Compressors, heat exchangers, expansion devices AC controls Cabin controls (cool occupants not cabin) Reduce Outside air to be treated Reheating of overcooled air Improve air distribution (e.g. climate control seats) Distributed HVAC systems Reduce overall AC system weight Alternative refrigerants

44 Fuel Used for Cooling and Dehumidification Denmark Sweden Norway Finland Percent of Time AC is Used for Cooling and Dehumidification 19.4 to to to 38.8 Totals Dehumid + Cooling, EU Billion Liters Billion kg CO2 25% Market % 100% Market % Percent of Total Consumption On average in Europe, about 4% of annual vehicle fuel goes for cooling and dehumidification this is a strong function of location United Kingdom Ireland Netherlands Poland Germany Belgium Czech Republic Austria Switzerland Hungary France Romania 38.8 to to to to to to 58.8 Cabin cooling uses 81% of AC fuel Currently (25% market penetration), 1% of fuel consumed across EU is used for running AC system Portugal Spain Italy Bulgaria Greece Turkey In the future (100% market penetration), 4% of fuel consumed across EU will be used for running AC system, unless AC system power is reduced

45 MAC fuel use & CO 2 emissions are strong functions of: Vehicle design Vehicle use Environment Solutions to reduce fuel consumed by MACs Reduce the load improve vehicle design Improve delivery design for occupant thermal comfort Improve equipment Educate consumers on impacts of driver behavior on MAC fuel use

46 Improve model assumptions presented here Verify usage patterns of vehicle AC with Real World Usage Study (blower speed, mode, temp ) Initiate vehicle usage survey similar to U.S. s National Personal Transportation Survey (trip length, trip distance, time of day travel ) Validate thermal comfort criteria to predict AC system usage Improve accuracy of power consumption models, to better value technologies (cost-benefit analyses) Use model to develop/continually update standardized tests Standardized tests assumptions (drive cycle, operating temperatures, etc) will greatly impact fuel consumption

WINDOW ENERGY LABELING IN COOLING SEASON: Fenestration & glazed structures

WINDOW ENERGY LABELING IN COOLING SEASON: Fenestration & glazed structures L A B O R A TO R Y O F B U I L D I N G C O N S T R U CT I O N A N D P H Y S I C S - D E P A R T ME N T O F C I V I L E N G I N E E R I N G ARISTOTLE UNIVERSITY OF THESSALONIKI WINDOW ENERGY LABELING IN