Secondary Loop Mobile Air Conditioner (SL-MAC) Demonstration Project

Transcription

1 Secondary Loop Mobile Air Conditioner (SL-MAC) Demonstration Project 39 th Open-Ended Working Group, Bangkok, Thailand 13 July 2017 Drs. Stephen O. Andersen & Nancy J. Sherman Institute for Governance & Sustainable Development (IGSD)

2 Market Drivers of HFC-134a Phasedown in MACs EU MAC Directive requires GWP <150 after 2016 for new automobiles sold in the European Union US EPA offers credit toward fuel mileage standards for low GWP US EPA lists HFC-134a as unacceptable in passenger cars and light-duty trucks as of Model Year 2021 Japan HFC regulations require low GWP MACs after Model Year 2023 Kigali HFC Amendment will Phase Down Worldwide 2

3 Atmospheric Impact of Mobile Air Conditioning Direct Greenhouse Gas (GHG) emissions Leakage of high Global Warming Potential (GWP) refrigerant to the atmosphere (through AC Hoses / Joints / Servicing / Accidents / End-of-Life) Atmospheric degradation products TFA HCOF COF HF Indirect GHG emissions CO 2 from exhaust (About 4% to 20% of fuel use is for air conditioning; depending on climate and traffic congestion) Atmospheric Degradation Products COF, HCOF, HF, TFA + R134a (HFC) Leakage 3

4 Technical Options to Replace HFC-134a in MACs Three refrigerant replacements approved by the USEPA SNAP also satisfy the EU F-Gas Directive (GWP<150) Safe use of HFC-152a requires secondary-loop for active safety system to prevent refrigerant leakage into the car interior SNAP / F-Gas Option GWP Efficiency TFA Flammable Application Patent HFO-1234yf < 1 Good Yes Slightly Yes *GWP from Intergovernmental Panel on Climate Change Assessment (IPCC) Assessment Report 5 (AR5) Carbon Dioxide - = 1 High CO 2 Ambient Temperature No No No HFC-152a = 138 Better No Yes No 4

5 Important Differences in Refrigerant Performance HFO-1234yf is ~5 to ~8% less energy efficient than HFC-134a, but added internal heat exchanger can offset up to 7%; thus the proper economic analysis adds the cost of the internal heat exchanger, if required, to the added cost of HFO-1234yf refrigerant HFC-152a is ~10% more efficient than HFC-134a, but an internal heat exchanger does not increase capacity and fuel efficiency HFO-1234yf charge is 10%, and HFC-152a 40%, smaller than HFC- 134a 17HX

6 Secondary Loop System vs Direct Expansion System Direct expansion system Andersen et al., 2014 Secondary loop system Andersen et al., 2014 SL-MACs use refrigerant to chill a fluid (coolant) that is circulated inside the car for comfort; a reduced charge of flammable refrigerants can be used more safely in systems with less emissions from fewer fittings and shorter refrigerant hoses. 6 7

7 Technology Demonstration: Secondary Loop for Flammable Refrigerants TATA Motors UNEP CCAC IGSD MAHLE Baseline Direct Expansion (DX) Dual AC System Apply SL-MAC system with improved Power Train Control logic to reduce short-lived climate pollutants (SLCPs) and maximize energy efficiency advantage Financial support by UNEP, as part of a climate change project of the Climate and Clean Air Coalition (CCAC) TATA Aria 2.2L Dicor is selected vehicle with front and rear A/C system Technical Advisors: California Air Resources Board (CARB), Chemours, Chrysler, Fiat, General Motors, Jaguar Land Rover, Neutronics Refrigerant Analysis, HF Consultancy, Natural Resources Defense Council (NRDC), Mobile Air Conditioning Society Worldwide (MACS), SAE International, Sun Test, TERRE Policy Centre, National Renewable Energy Laboratory (NREL), University of Maryland, and Valeo. 7 5

8 Challenges: Secondary Loop System Time to comfort in SL-MAC system is demonstrated to be equivalent to direct expansion (DX) systems despite the need to cool the intermediate coolant Added components increase vehicle weight and fuel use (very minor compared to overall fuel economy improvement obtained) and require extra effort to recycle at end of vehicle life It is always challenging to attribute measured improvements in fuel efficiency to specific design features; some innovations in the demonstration vehicle can also be applied to DX systems Unique to SL-MACs Regenerative cooling, powered cooling controlled for least fuel use, cold storage, low-cost multiple cooling points to reduce the energy use needed for comfort Both SL- or DX- MACs Compressor preferentially engaged on deceleration, water flow to heater controlled by valve in hot weather, and other enhancements to-be-determined during demonstration 8

9 Secondary Loop advantages and disadvantages over Direct Expansion System Advantage Less Refrigerant at Lower Cost Per Vehicle (e.g. 2 or > cooling points) Manage Refrigerant Risk Use Stored Cold Energy Coolant Distributed Cooling Easy Extension to Heating Improved Noise, Vibration, and Harshness (NVH) Deceleration Cooling Potential Cost Advantages to Vehicle Owners Disadvantage Additional Components and Mass Package Size (parts + volume) Lower Coefficient of Performance (COP) that can be mitigated by SL-MAC engineering choices Key Project Objective: Increase the SL-MAC coefficient of performance (COP) and Life-Cycle Climate Performance (LCCP) beyond that of a DX system with Latest Thermal and New Powertrain Technology 9

10 Economic Framework Manufacturing Secondary loop (SL) is the economic choice when added SL components cost less than the difference between HFO-1234yf and HFC-152a refrigerant costs Ownership SL is the economic choice if cost savings from less frequent service and fuel savings are greater than the added cost of the system components Sensitivity Analysis is Essential Declining cost of refrigerants from mass production and competition Application patents for HFO-1234yf in MACs will expire by 2023 in most markets Both HFO-1234yf and HFC-152a qualify for the U.S. low-gwp credit toward fuel efficiency Credits for off-cycle fuel savings may be a game-changer in favor of SL-MACs (deceleration cooling and prolonged comfort in vehicles with stop/start) 10

11 Preliminary Findings SL-MAC Economics Manufacturing Single-point cooling HFO-1234yf with internal heat exchanger (if necessary) is likely the least cost short-term manufacturing option where engine real estate is limited Two or more cooling points - HFC-152a is clearly the least cost system, with co-benefits in durability and customer satisfaction - Ownership SL-MAC cost advantages of less frequent service and fuel savings overwhelms manufacturing cost disadvantage 17HX

12 March 2017 Refrigerant Cost Comparison Indicative Single-Point Automobile & Light Truck Systems Refrigerant OEM cost/kg Retail cost/kg Cost charge Cost recharge HFC-134a $8.00 $16.79* $5.60 (700 grams) $11.76 (700 grams) HFO-1234yf $80.00 $220.00* $ (630 grams) $ (630 grams) HFC-152a ~$5.00 ~$10.00 ~$ (420 grams) ~$ (420 grams) Indicative Multi-Point & Heavy Truck Systems Refrigerant OEM cost/kg Retail cost/kg Cost charge Cost recharge HFC-134a $8.00 $16.79* $12.80 (1600 grams) $26.86 (1600 grams) HFO-1234yf $80.00 $220.00* (1440 grams) $ (1420 grams) HFC-152a ~$5.00 ~$10.00 ~$ (960 grams) ~$ (960 grams) *13 March 2017 Refrigerant Prices O Reilly Auto Parts: 10 pounds $199.00; 30 pounds Accounting for the 10% and 40% reduction in system charge for HFO-1234yf and HFC-152a, respectively 12

13 MAC Kigali Amendment Business Opportunities Investment Certainty of Global Transition from HFC-134a Anticipate HFC-134a restriction in export markets Reduced Emissions in Servicing and End-of-Life Training and tools for servicing with HFC-134a and new refrigerants Agreed Incremental Cost of Re-Tooling manufacturing in A5 Parties Paid by Montreal Protocol Multilateral Fund (MLF) Downstream costs of MAC service and Fuel Use

14 Thank you for your attention! SL MAC System: Concept Demonstration Model Questions

15 Backup Slides Follow

16 Team Members Tata Motors Ltd (TML) - Sangeet Kapoor, Prasanna Nagarhalli, Jagvendra Meena MAHLE - Sourav Chowdhury, Timothy Craig, Lindsey Leitzel Institute for Governance & Sustainable Development (IGSD) Dr. Stephen O. Andersen, Dr. Nancy J. Sherman, Melinda Soffer JAB Consulting Jim Baker

17 Cooling Degree Days & Population Source: Davis et al, Proceedings of the National Academy of Sciences,

18 Kigali HFC Amendment Unanimous Agreement of all Nations Phase-down HFCs on Differentiated Schedules that can be Accelerated Most Developed Countries First Russia and Affiliated Countries Second Vast Majority of Developing Countries Third Developing Countries in High Ambient Regions Last Increased Energy Efficiency Anticipated (SAE LCCP Metric for Vehicles) Financing of Agreed Incremental Costs for Developing Countries Qualified Under Article 5 of the Montreal Protocol

19 The Montreal Protocol Phaseout of Ozone-Depleting Substances (ODSs) The Montreal Protocol has slowed and reversed the accumulation of ozone depleting substances (ODSs) in the stratosphere, as measured by effective stratospheric chlorine amounts. Stephen A Montzka, NOAA/ESRL,

20 The Montreal Protocol ODS Phaseout Protects Climate!. The Montreal Protocol reduced net GWP-weighted emissions from ODS in 2010 by 11 Gt CO2- eq yr -1. This is 5-6 times the reduction target of the first commitment period ( ) of the Kyoto Protocol. Guus JM Velders, Stephen O Andersen, John S Daniel, David W Fahey, and Mack McFarland, PNAS,

21 Kigali Amendment: HFC Phasedown Schedule in Article 5 Parties (mostly developing countries) Source: OzonAction Fact Sheet The Kigali Amendment to the Montreal Protocol: HFC Phase-down, 2016

22 Kigali Amendment: HFC Phasedown Schedule in Non-Article 5 Parties (mostly developed countries) Source: OzonAction Fact Sheet The Kigali Amendment to the Montreal Protocol: HFC Phase-down, 2016

23 Extraordinary Benefits of HFC Phasedown Source: UNEP, Montreal Protocol and the Green Economy (2012) 23

24 The Kigali Amendment is the Start that will be Strengthened! 24

25 Protocol & Market Drivers of HFC-134a Phasedown in MACs Protocol Drivers The 2016 Kigali Amendment Reduction in Short Lived Climate Pollutants (SLCP) HFCs The 1997 Kyoto Protocol already controls HFC emissions The 2016 Montreal Protocol Amendment will control HFC production and consumption and will finance the transition by developing countries to lower GWP refrigerants and higher energy efficiency Market Drivers EU MAC Directive requires GWP <150 after 2016 for new automobiles sold in the European Union US EPA offers credit toward fuel mileage standards for low GWP US EPA lists HFC-134a as unacceptable in passenger cars and light-duty trucks as of Model Year 2021 Japan HFC regulations require low GWP MACs after Model Year

26 Technical Options to Replace HFC-134a in MACs Three refrigerant replacements approved by the USEPA SNAP also satisfy the EU F-Gas Directive (GWP<150) SNAP / F-Gas Option GWP Efficiency TFA Flammable Application Patent HFO-1234yf < 1 Good Yes Slightly Yes Carbon Dioxide - CO 2 = 1 High Ambient No No No HFC-152a = 138 Better No Yes No *GWP from Intergovernmental Panel on Climate Change Assessment (IPCC) Assessment Report 5 (AR5) HFO-1234yf, although costly (bulk cost increased by 10~12 times), is leading with 35 manufacturers, 125 models so far 24 million vehicles sold by year end 2016 Audi and Daimler selected CO 2 (R744) based on non-flammability, and limited regular production has started on selected models. Automobile companies know how to safely use flammable fluids (fuel, hydraulic fluid, motor oil, brake fluid, antifreeze, and windshield cleaning fluid are all flammable) 26

27 Baseline Test Plan S.No Test Test Condition Baseline Test Status 1 Air discharge measurement Front and Rear-All blower speed Completed Stationary AC performance test in Moderate Ambient- (Open Door Close Door)-Max Blower, Max Cool Stationary AC performance test in Severe Ambient- (Open Door Close Door)-Max Blower, Max Cool Transient AC Performance test in Moderate Ambient-Max Blower, Max Cool Transient AC Performance test in Severe Ambient-Max Blower, Max Cool 35 C, 40 % RH 45 C, 40 % RH 35 C, 40 % RH, 1000 W/m2 Solar Load 45 C, 40 % RH, 1200 W/m2 Solar Load Completed Completed Completed Completed 6 Kolkata City cycle AC Performance test-max Blower, Max Cool 38 C, 50 % RH, 800 W/m2 Solar Load Completed 7 Mumbai City Cycle AC Performance test-max Blower, Max Cool 40 C, 60 % RH, 800 W/m2 Solar Load Completed 8 Compressor power consumption 9 10 Thermal Comfort - Moderate Ambient Transient AC Performance test- Max Blower, Max Cool Thermal Comfort - Severe Ambient Transient AC Performance test Max Blower, Max Cool 35 C, 40 % RH, 1000 W/m2 Solar Load 35 C, 40 % RH, 1000 W/m2 Solar Load 45 C, 40 % RH, 1200 W/m2 Solar Load Completed Completed Completed 11 Fuel Economy and Emmision Test Indian Drive Cycle Completed 27 6

28 TATA Aria Baseline Testing Component Level Tests - Individual Components: Evaporators (F & R), Condenser - Chiller-Cooler Combination Chiller Cooler Pump System Bench Testing (per GreenMAC LCCP criteria) Vehicle Wind Tunnel Testing

29 Energy Benefits of Secondary Loop Simulated Fuel Economy With Cold Storage Conditions: A. No A/C B. Continuous A/C with Cabin Soak to Ambient Condition C. B + Compressor Disengaged at Speed = 0 (Engine runs at idle) D. B + Compressor Disengaged at Speed = 0 OR Acceleration >0 FTP75 (mph) NEDC (kph) SC03 (kph) A B C D Fuel Econ (mpg) No A/C Continuous A/C Compressor Stop at idle Compressor Stop at Idle+Accl. Gain = (D-B)/Bx100 (%) FTP75@28 C % NEDC@28 C % SC03@35 C % Chart of Simulated Fuel Economy Improvement, Dr. S. Chowdhury, MAHLE Demonstrates the Potential Fuel Economy Benefit of SL-MAC 29

30 Project Plan Task Name Baseline Vehicle Assessment Component & System Development Vehicle Build,Emissions & Wind Tunnel Tests PowerTrain Logic Implementation Road and Tunnel Evaluation in India Final Energy Analysis and Report Q3 Q4 Q1 Q2 Q3 Q4 Q1 MAHLE Receives Vehicle TML Receives Vehicle 30 6