High Efficiency Technologies for Small and Medium-Sized Air Conditioning Equipment Using R410A. Hitachi Appliances, Inc.

Transcription

1 1 High Efficiency Technologies for Small and Medium-Sized Air Conditioning Equipment Using R410A Hitachi Appliances, Inc.

2 2 Introduction The situation faced by the refrigeration / air conditioning industry has become increasingly severe, because ODP CFCs: abolished in 1995 in developed countries HCFCs: must be reduced to practically zero by 2020 GWP Must reduce greenhouse gas emissions according to COP3 What should we do to minimize CO 2 emissions? One solution is to develop high-efficiency AC equipment using HFCs In this presentation, examples of high-efficiency technology used in small and medium-sized air conditioning equipment and lessons for changeover to HFC refrigerants will be shown.

3 3 To utilize HFC refrigerants, we have considered 1. Optimization of specifications for each component such as compressors, heat exchangers, refrigeration cycles 2. Assembly line conversions to produce A/C equipment using HFCs 3. Minimization of material costs 4. Training for installation and servicing

4 4 Introduction of HITACHI Group Revenue by Industry Segment Information & Telecommunication Systems Electronic Devices Power & Industrial Systems Logistics, Services & Others High Functional Materials Household Appliances & A/C Products All figures include Eliminations and Corporate items, FY2005/Consolidated basis

5 HITACHI Worldwide Total 932 Companies 355,879 Employees *Including Hitachi, Ltd. Hitachi Europe Ltd. Maidenhead, UK Hitachi (China), Ltd. Beijing, China Japan 477 Companies 242,659 Employees North America 75 Companies 15,514 Employees Europe 88 Companies 5,354 Employees Asia (including China) 251 Companies 86,796 Employees Hitachi Asia Ltd. Singapore Hitachi, Ltd. Tokyo, Japan China 133 Companies 40,359 Employees Hitachi America Ltd. Brisbane, CA, U.S.A Other Areas 42 Companies 5,556 Employees Consolidated figures for FY2005, ended March,

6 6 Small and Medium-Sized Air Conditioning Equipment Outdoor Unit Indoor Units Copper Pipe (Gas Line) Copper Pipe (Liquid Line)

7 7 Variation of A/C units Indoor Units Outdoor Units

8 8 Comparison: HCFCs & HFCs HCFC HFC Refrigerant R22 R407C R410A Components HCFC22 HFC32/125/134a HFC32/125 (100%) (23/25/52wt%) (50/50wt%) ODP * GWP * Pressure at MPa 1.19MPa 1.65MPa at MPa 2.21MPa 3.06MPa Lublication Oil Mineral Ether Ether Ester Ester *1:Scientific Assessment of Ozone Depletion: 2006, National Oceanic & Atmospheric Administration *2:IPCC2007 4th Assessment Report

9 9 Technology for High Efficiency and Reliability in Compressors Compressor Output (kw) Type for Use Room A/C Packaged A/C Room A/C Packaged A/C Domestic Ref. A/C, Domestic Ref. Ref Chiller A/C Ref Chiller Reciprocating レシフ ロ式 Rotary ロタリ式 Scroll スクロル式 Room A/C Packaged Room A/C A/C Commercial Packaged A/C Ref. Commercial Ref Centrifugal 遠心式 Chiller Industrial Chiller Ref. Industrial Ref Screw スクリュ式 Chiller Commercial Chiller & Commercial Industrial Ref. & Industrial Ref

10 Scroll Compressor Reliability New circular oil supply structure Efficiency Optimizing scroll wrap profile to reduce leakage & mechanical loss Adopting asymmetric scroll Inside chamber Fixed scroll Putting sub-bearing below the motor Ether lubricant oil Orbiting scroll Outside chamber Symmetric Asymmetric Optimizing stroke volume according to refrigerant characteristics DC motor 10

11 11 Rotary Compressor Reliability Suitable materials for roller and vane Efficiency DC motor Injection 2-stage compression system with injection Ester lubricant oil

12 12 Technology for High Efficiency in Heat Exchangers Purpose To increase heat transfer rate To reduce pressure loss To increase amount of Subcooling Measures High angle Micro-fin tubes Double-sided louvered fins Improvement of refrigerant flow

13 13 Cooling COP Heating COP Heat Transfer Tube Conventional Height Hf 0.23mm 0.20mm Number of Groove Angle a 12 deg. 35 deg. 100% 100% New Type 101.7% 102.4% α Hf Height Screw Angle Refrigerant Flow

14 14 Heat Transfer Fin One Side Offset Louver Fin (Conventional Fin) Both Side Offset Louver Fin (Improved Fin)

15 15 Effect of Both Side Offset Louver Fin One Side Offset Louver Fin (Conventional Fin) Air Air Both Side Offset Louver Fin (Improved Fin) Leeward fins are not affected by temperature of windward fins Temperature Overall Heat Transfer Coefficient (W/K) Both Side Offset Louver Fin 0.8 One Side Offset Louver Fin 1.0 Velocity of Air Flow Fig. Effect of Both Side Offset Louver Fin Overall Heat Transfer Coefficient +10% 2.0 (m/s)

16 16 Technology for High Efficiency in Refrigeration Cycle Refrigeration Cycle, which is the combination of components System Optimization Purpose To increase coefficient of performance satisfying its capacity

17 17 (1) Gas Injection Cycle Indoor Unit Heat Exchanger Outdoor Unit Fan Conventional cycle G Pressure G i Compressor G-G i Outdoor Unit Heat Exchanger Outdoor Unit Expansion Valve Gas Liquid Separator Tank Gas Injection Circuit Enthalpy Gas injection cycle 1Compression work is reduced. 2Pressure loss is reduced.

18 18 (2) Subcooling Bypass Cycle Outdoor Unit Heat Exchanger Indoor Unit Heat Exchanger Bypass Circuit Bypass Compressor Heat Exchange Subcooling Heat Exchanger 1Capacity becomes higher.

19 (3)(i) COP Improvement Effect Example of model 140 (Rated Cooling Capacity 12.5kW) HCFC: R22 Unit HFC: R407C Unit HFC: R410A Unit 19

20 Average COP (3)(ii) COP Improvement Effect (a)cop Improvement (5HP) 3.60 Subcooler 0.06 DC Fan Motor 0.13 DC Compressor Motor 0.19 R Refrigeration Cycle 0.27 Compressor 0.10 DC Fan Motor R407C Deterioration by R407C 4.40 Gas Injection Compressor 0.23 Heat Exchanger 0.13 Others Change to R410A 0.13 R410A Improvement by R410A (b)annual CO 2 Emission Reduction 2,400 46% Cut kg/year 1,300 kg/year Previous Model(R22) New Model(R410A) 20

21 21 (4)(i) Leak Tightness Design Pressure becomes: R22 R407C R410A 3.0MPa 3.3MPa 4.15MPa(depends on equipment) (a)thickness of some components... larger ex.)pipe according to Japanese Regulation t = PDo 2σ η + 0.8P a + α where t :minimum thickness of pipe P :design pressure D o :outer diameter of pipe σ a :allowable stress of the material η :efficiency of welding α :margin against corrode (for cupper pipe, α=0)

22 (4)(ii) Leak Tightness (b)types of parts (flare nut, etc.)... changed Diamet er R22 (HCFC) Type 1 R410A (HFC) Type 2 A B A B φ φ JIS B8604:2002 (c) Higher durability of other parts for example, expansion valve, solenoid valve, 4-way valve, stop valve, pressure sensor, etc. (d) Higher pressure for leak test (although detection value of leak test is set the same) 22

23 23 Conversion of Facilities at Assembly Line Oil charger, Refrigerant charger, etc...changed

24 24 Material Cost From characteristics of R410A, some component dimensions can be more compact...cost down Example of model 140 Cost 100% 97% 97% COP 100% 106% 122% Cost Ratio (%) 120% 100% 80% 60% 40% 20% 0% 100% 97% 97% R22 R407C R410A

25 25 Caution at Installation and Servicing (a) Example of Evacuation and Refrigerant Charge Stop Valve (Liquid) Stop Valve (Gas) Manifold Gauge Nitrogen Tank Outdoor Unit Vacuum Pump Refrigerant Cylinder (R410A) Scale

26 Caution at Installation and Servicing (b) Tools for Installation and Servicing Pipe cutter,bender, Flaring tool R407C (HFC) R410A (HFC) Lubricant oil Refrigerant cylinder Vacuum pump Manifold valve, Charging hose :Interchangeability with R22(HCFC) :only for R407C(HFC), :only for R410A(HFC) 26

27 27 Quality Control of Contamination at Installation To prevent hydrolysis, content of water and contamination in the refrigeration cycle should be suppressed by sufficient vacuuming as follows: (example of HITACHI) R22 :-0.1MPa, 2hours (5 Torr) R410A:-0.1MPa, 2hours (5 Torr) the same

28 28 Conclusion In converting from HCFCs to HFCs Environmental benefits are realized Zero ODP Improved efficiency of A/C equipment reduced CO2 emissions Material cost of equipment can be minimized by optimizing each component Several specification changes, conversion of facilities, and preparation of tools are required

29 Together with energy saving technology, the adoption of HFCs are issues of growing importance these days, and will be necessary to continue forging ahead with development of technology. 29

30 ref1 (reference) Pipe Thickness and Material for installation Diameter R22 R410A Thickness Material Thickness Material φ O 0.8 O φ O 0.8 O φ O 0.8 O φ O 1.0 O φ O 1.0 1/2H φ O 1.0 1/2H φ O 1.0 1/2H φ O 1.0 1/2H φ O 1.1 1/2H φ O /2H

31 ref2 (reference) LCCP Evaluation (10 years) Recovery Rate 30% Recovery Rate 70% % Direct % Direct LCCP (CO2-kg) Indirect 59% Direct LCCP (CO2-kg) Indirect 53% Direct Indirect 5000 Indirect 0 R22 RM R410A RM 0 R22 RM R410A RM