R744 MAC Systems from conventional driven vehicles to EVs October 2009

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Content Natural Refrigerant R744 (CO 2 ) for MAC System Experience Phase 1: Functionality R744 AC & Heating System Phase 2: Performance AC & Heating Systems Phase 3: Controllability AC Phase 4: Driveability & Cost for Small Vehicles AC Phase 5: COP System Optimisation AC Phase 6: Durability Tests AC Systems E-Vehicles, Hybrid electrical Vehicles and PHEV

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. No ozone depletion; ODP = 0 Lowest possible GWP of 1 Classified under the American Standard Heating and Refrigeration (ASHRAE) as A1 Non toxic and non flammable R744 is one of the best known and understood substances in term of scientific research and applications. Humans inhale and exhale it Mankind puts it in soda and drinks it It is a natural substance of the atmosphere Highest efficiency, lowest indirect emissions and best LCCP vs. all others Lowest total cost of ownership Why Natural Refrigerant R744 (CO 2 )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. System Experience OE has build up more than 50 prototype vehicles with R744 – Systems Future development trends towards Electrical Vehicles with A/C and HP HEV and PHEV with A/C and HP Battery cooling Thermal management

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. OE System Experience R744 Function System Control Small Vehicle COP System Durability Testing AC & Heating Systems AC Systems Only Performance

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Phase 1: Functionality R744 AC & HS ( ) First development steps with R744: Demonstrate that R744 operates as refrigerant under all climate conditions Show the functionality of - Single AC-System - Coolantside Heat Pump System - Air Side Heat Pump System - Hot Gas Cycle System Therefore several cars were equipped with R744- Systems … … Audi … Daimler … BMW

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. HVAC Evaporator Gascooler Compressor Accu Air IHX HP Valve LP Valve P/T EXV Heating Mode: System Description: Air Heat Pump System Phase 1: Functionality R744 AC & HS ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Phase 2: Performance AC & HS ( ) Optimisation of the Cooling- and Heating Performance in R744 Systems Vehicle model build up

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. AC Pull Down Results R744 vs. R134a (Full Size Truck) Comfort Temperature 22°C 50 kph REC 80 kph REC 50 kph OSA 80 kph OSA IDLE REC 110 kph OSA 18 min 10 K Phase 2: Performance AC & HS ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Heat Up Result Hot Gas System R744 Hot Gas Cycle Coolant & Fuel Fired Heater Coolant Comfort Temp. 22°C 14 min 21 min 28 min - R744 HG Cycle - Coolant & FFH - Coolant Cabin Head Temperature Ambient temperature = -10°C Phase 2: Performance AC & HS ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Time [ min ] Pressure Tunnel In Tunnel Out Speed variation Blower variation Pressure [ bar ] Phase 3: Controllability AC ( ) Targets: - Same or better controllability as R134a systems - Safe handling of the high system dynamic - Noise and torque optimised controlling

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Time [ min ] 9 °C 12 °C 6 °C 3 °C 9 °C 6 °C 3 °C System conditions: Cycle:Forced Idle n_engine:2000 rpm Blower:7 T_Evap:Variable Compr.:Variable - Stable outlet temperature within the control range of 3°C – 12 °C Evaporator Temperature Setpoint Variation Phase 3: Controllability AC ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Phase 4: Driveability & Cost for Small Cars ( ) Vehicle Build Up for Different OEMs Small compressors, optimized heat exchangers and control strategy have been applied to show the AC functionality in small cars with low torque engines

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Md [%] t [-] M Eng 35/120 bar Engine torque M Com Pcomp [%] t [-] P max 35/120 bar P Idle Compressor torque Max. Cooling power point Compressor torque Controlling Strategy Phase 4: Driveability & Cost Small Cars ( ) ~ ~ M Com Md [%] Adjustable max torque timing Available engine torque

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Solution: Small Car Low Cost AC-Systems Small size fixed or variable displacement compressor Application adapted and optimized control strategy Coaxial IHX as part of lineset MCP Evaporator and Gascooler Full Flexible Tubing System PXV-System Result: Perfect drivability for small cars with R744 AC-Systems Phase 4: Driveability & Cost Small Cars ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Phase 5: COP System Optimisation AC ( ) Phase 5 was motivated to further improve COP and reduce fuel consumption of R744 AC systems The development phases 1 to 4 were focused on functionality and performance of R744 Systems

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Vehicle Test Results – Fuel Consumption NEDC Fuel Consumption Test R134a vs. R744 VW Touran TDI 1,9l; T ambient =20/28/35degC Additional Fuel Consumption R134aAdditional Fuel Cons. R744 T ambient Additional Fuel Consumption l/100km

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Phase 6: Durability Tests AC Systems ( ) OE has built up several vehicles with different R744 systems for durability testing at Obrist and Costumers Obrist Engineering Vehicles (AC and Heating Systems) Audi A4 1.6l Single AC-System Build up: 1999 Mileage: ~ km More then 10 years of city cycle operation !! Ford Galaxy 1,9TDI AC & HG System and MCP Build up: 2003 Mileage: ~ km R&D vehicle

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Kia Sportage 1,9 TDI Single AC-System Build up: km Durability Test in Dubai VW Lupo 1,0 Single AC-System Build up: 2004 Accelerated Lifetime test km OE has built up several vehicles with different R744 systems for durability testing at Obrist and Costumers Costumer Vehicles (AC Systems) Phase 6: Durability Tests AC Systems ( )

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. EVs, HEVs and PHEVs EVs, HEVs and PHEVs have additional needs for cooling and heating compared to conventional vehicles Cabin heating and cooling Battery cooling Efficiency in cooling and heating becomes key, since any energy required for heating and/or cooling needs has to be drawn from the battery High battery cost Range reduction issue

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. EV Heating System Consequences Electrical HeatingR744 HP NEDC wheel average3kW Heating requirement6kW1,5kW NEDC theo. range90km 20degC real range60km -20degC real range20km45km Vehicle becomes useless

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Example: Air Side Heat Pump for EV High Efficient E-Compressor

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. Cartridge AC - System Battery Box Li-Ion Battery Cooling System Development Coolant to Refrigerant to Air

Confidential © All rights with Obrist Engineering GmbH also in the event of the grant of a patent. Right of disposal like copying and distribution with us. R744 Development for conventional driven vehicles completed R744 Development for Evs, HEVs and PHEV under way R744 is the future refrigerant since it is the only refrigerant fullfilling all the requirements for MACs and battery cooling systems ODP and GWP COP and Efficiency Cost HP capability Summary