Army Sustainability Workshop P R ES E N T E D BY L E BA N O N G R E E N B U I L D I N G CO U N C I L ( LG B C ) NOVEMBER 12 – 13 – 19 DECEMBER 1 & 8
VRF VS CHILLED WATER SYSTEMS LOW RISE RESIDENTIAL BUILDING – DUBAI: CASE STUDY
PRESENTED BY, ENG. ELIE FADOUS
CONTENTS 1.
OBJECTIVES
2.
METHODOLOGY
3.
PROJECT DESCRIPTION
4.
COOLING BLOCK LOAD
5.
HVAC SYSTEMS DESCRIPTION: AIR COOLED CHILLER, VRF-OPTION I, VRFOPTION II
6.
INITIAL COST
7.
RUNNING COST
8.
MAINTENANCE AND SPARE PARTS
9.
LIFE CYCLE COST
10. ANALYSIS: TECHNICAL, FINANCIAL AND MAINTENANCE MANAGEMENT
1 - OBJECTIVES Assess the merits of an Air conditioning system Comparison between Air cooled chilled water system and : A) Roof located VRF outdoor units; B) Floor located VRF outdoor units How and what would be the benefits?
2 - METHODOLOGY Load calculation will be based on an Hourly analysis program Load calculation profile will be an hourly profile covering the entire year
Selection of equipment (High ambient temperature)
2 - METHODOLOGY AC systems layouts, schematic risers and schedule of equipment
Detailed yearly Electrical power inputs schedule
Life cycle cost comparison table
Analysis Table
3 - PROJECT DESCRIPTION The project consists of: • 1 basement used as car parks. • GF consists of shops. • 3 Podiums with lobbies and Tech area; the rest is used as parks. • 1st floor that includes a health club. • 7 typical Residential floors, each of 10 Apartments. • Roof Floor. • Total cooled area around: 6735m2 • Total Built up area: 15000 m2.
Typical floor plan
4 - PROJECT COOLING BLOCK LOADS Cooling Block loads have been calculated based on Hourly Analysis program Ventilation rates are based on ASHRAE standard 62.1
Summary table: BLOCK COOLING LOAD BL1 BL2
KW 1140 900
TR 325 255
Where: • BL1 represents the building cooling block load. • BL2 represents the building cooling block load with vent reclaim
Cooling loads have been done based on Dubai Weather Conditions as per Decree 66: 46C DB, 29C WB.
5 - SYSTEMS DESCRIPTION Chilled water system • 2x580 Kw=330TR Air cooled chillers (located on roof)
• Primary loop, on roof, with set of constant speed pumps: 2 pumps in duty +1 standby • 1 set of Secondary variable speed Pumps loops (roof): 2 pumps in duty + 1 stand by
• 2 Fresh air handling units with recovery heat wheel (110 Kw or 31TR) • AHU and FCU with 2 way modulating control. • Chilled water pipes distribution system with insulation
• Building management system • Energy metering system
5 - SYSTEMS DESCRIPTION
Indoor units
Fresh air Handling unit
Air cooled chiller
5 - SYSTEMS DESCRIPTION VRF system option 1 (Roof outdoor units) • 24 VRF Outdoor units located on roof having a total corrected load of 1250 kw • 152 VRF indoor units • 2 DX Fresh air handling units with recovery heat wheel (110 Kw or 31TR) • Refrigerant copper pipes with insulation • Intelligent controller system including power proportion distribution (PPD) system for energy metering.
5 - SYSTEMS DESCRIPTION VRF system option 2 (Same floor outdoor units) • 24 VRF Outdoor units located on the same floor having a total corrected load of 1250 kw • 152 VRF indoor units • 2 DX Fresh air handling units with recovery heat wheel (110 Kw or 31TR) • Refrigerant copper pipes with insulation • Intelligent controller system including power proportion distribution (PPD) system for energy metering.
5 - SYSTEMS DESCRIPTION
Indoor units
Fresh air Handling unit
Outdoor unit
6 - INITIAL COST Chiller system VS VRF system (Option 1) • Chiller Option - Initial cost is around $1,109,609 • VRF option 1 - Initial cost is around $1,519,000
Increase in installed cost of VRF Option 1 vs Chiller Option :
+410,000$ = +37%
6 - INITIAL COST Chiller system VS VRF system (Option 2) • Chiller Option - Initial cost is around $1,109,609 • VRF option 2 - Initial cost is around $1,437,878
Increase in installed cost of VRF Option 1 vs Chiller Option :
+329,000$ = +30%
7 - RUNNING COST The sum of hourly running cost through a whole year leads to the yearly running cost. The calculation has been based on: • Dubai Hourly outdoor temperature profile • Detailed schedule showing the hourly cooling load kwh through the whole year based • Hourly Electrical Power inputs schedule for both systems calculated via special software taking in consideration above items a and b. • Yearly running cost has been calculated based on 0.1035 $ per Kwh
7 - RUNNING COST Dubai Hourly outdoor temperature profile (°C): Month of August (sample) 0:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00
1 32.3 32.1 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.6 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.2 36.2 35.4 34.6 33.8
2 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.6 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.2 36.2 35.4 34.6 33.8
3 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.6 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.4 34.6 33.8
4 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.4 34.6 33.8
5 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.4 34.6 33.8
6 33 32 32 32 31 31 31 32 33 34 35 37 38 39 39 39 39 39 38 37 36 35 35 34
7 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.4 34.6 33.8
8 33.1 32.4 31.9 31.7 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.4 34.6 33.8
9 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
10 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
11 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
12 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
13 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
14 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.2 36.8 37.9 38.6 38.9 39 38.9 38.5 37.9 37.1 36.2 35.3 34.6 33.8
15 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.3 36.8 37.9 38.6 38.9 39 38.9 38.5 37.8 37.1 36.2 35.3 34.5 33.8
August 16 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.5 33.7 35.3 36.9 37.9 38.6 38.9 39 38.9 38.5 37.8 37.1 36.2 35.3 34.5 33.8
17 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.5 37.8 37.1 36.2 35.3 34.5 33.8
18 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.5 37.8 37.1 36.2 35.3 34.5 33.8
19 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.5 37.8 37.1 36.2 35.3 34.5 33.8
20 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
21 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
22 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
23 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
24 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
25 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.7 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
26 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.2 35.3 34.5 33.8
27 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.1 35.3 34.5 33.8
28 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.1 35.3 34.5 33.8
29 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.3 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.1 35.3 34.5 33.8
30 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.4 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.1 35.3 34.5 33.8
31 33.1 32.4 31.9 31.6 31.4 31.3 31.4 31.8 32.6 33.8 35.4 36.9 38 38.6 38.9 39 38.9 38.4 37.8 37.1 36.1 35.2 34.3 33.4
7 - RUNNING COST Hourly cooling load schedule (KW): Month of August (Sample) 0:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00
1 587.1 584 589.6 573.9 572.7 573.2 573.8 580.4 588.3 616.6 626.6 651.4 661.5 666.5 682.5 674.7 674.7 685.7 664.1 654.5 653.5 636.4 629.4 628.3
2 607 598.4 606.4 585.3 579.2 585.9 589.3 588.7 607 618.6 627.9 658.4 664.9 688.1 689.5 677.8 676.7 680.1 679.3 659.2 658.7 649.5 638.9 617.4
3 612.9 611.7 595 587.3 594.5 576.8 593.9 599.9 599.1 621.7 640.7 644.5 675.4 668.2 682.1 692.7 680.3 677.2 686.3 655.5 648.1 652 627.1 624
4 621.7 603.6 594.8 601.7 578.8 581.1 584.4 592.9 602.6 626.2 639.7 657.6 660.7 673.4 695.6 680.5 686.2 689.4 671.9 659.5 663.3 637.1 635.4 633
5 608 608 608 589 582 591 594 591 609 624 631 658 669 691 674 684 695 676 672 672 646 644 640 622
6 614.8 614.3 594.7 589.2 593 574.4 588.9 588.1 613.6 618 644.3 644.5 665.6 683 682.6 694.3 677.3 697.3 676.8 669.3 646.5 651.6 628.5 621
7 625 599 599 599 582 577 587 600 606 628 644 645 666 674 694 674 688 678 673 671 647 645 642 620
8 611 613 598 591 591 579 599 595 602 625 641 648 674 669 684 695 680 679 687 666 658 640 629 632
9 609 606 605 589 583 588 591 588 608 624 629 660 661 676 692 678 698 688 679 659 659 637 633 630
10 612 602 608 585 585 585 596 592 609 623 631 659 665 673 694 675 684 682 681 655 651 648 632 620
11 623 601 600 597 584 579 583 603 594 613 635 662 657 674 686 694 681 693 675 678 666 643 628 621
12 623 609 610 595 582 588 591 586 609 620 631 657 666 672 684 692 681 687 679 666 647 651 625 623
13 620 603 594 599 578 579 591 590 608 621 640 655 668 685 678 687 688 680 681 663 658 637 643 618
14 615 614 591 590 590 577 596 589 616 619 631 657 656 693 683 693 680 677 681 655 651 648 630 622
August 15 618 602 599 597 581 577 585 598 596 618 630 663 658 677 692 679 688 679 682 656 648 653 627 619
16 623 599 600 599 581 577 595 585 613 621 639 650 664 676 682 696 678 691 677 673 653 637 644 627
17 619 603 596 597 580 576 594 589 609 621 642 644 662 688 676 683 692 684 660 670 646 643 638 622
18 612 614 591 592 591 577 593 598 596 626 638 652 674 669 693 677 675 680 672 668 650 639 644 619
19 611 617 593 589 594 573 598 594 613 617 624 651 673 672 680 688 692 679 670 670 646 643 640 620
20 611 616 594 589 593 574 597 595 597 625 640 649 675 672 686 692 683 678 679 654 650 648 631 622
21 618 605 597 601 578 581 579 603 604 622 632 662 662 677 692 682 681 690 667 660 658 639 629 634
22 607 607 606 589 585 586 589 589 606 625 633 662 664 677 692 678 687 671 686 671 654 642 645 620
23 622 602 596 599 577 580 580 597 603 616 638 658 662 689 674 682 684 685 669 655 660 636 633 633
24 608 605 604 588 583 584 578 592 600 623 640 655 669 694 685 698 682 683 666 657 659 636 633 629
25 610 603 605 585 584 584 582 589 597 624 639 652 674 678 696 674 691 698 654 669 650 647 627 620
26 623 598 599 596 580 579 589 588 608 621 648 658 677 671 683 694 677 673 671 668 647 639 642 617
27 609 614 592 591 590 577 594 593 605 614 643 647 665 688 677 693 684 686 677 666 643 641 638 620
28 610 615 593 587 592 574 595 595 599 623 643 650 678 674 682 697 680 677 678 654 651 648 628 620
29 623 600 597 595 582 577 581 598 615 627 637 668 661 690 675 697 681 676 678 653 650 649 625 622
30 620 601 596 600 579 579 588 588 609 620 644 655 678 683 690 685 692 673 664 669 652 650 623 623
31 622 598 595 598 577 579 589 584 610 618 645 643 666 688 676 689 698 669 669 654 652 645 629 620
7 - RUNNING COST Electrical consumption (KWh) – Chillers system: Month of August (Sample) 0:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00
1 176.33 174.73 175.42 170.51 169.02 168.76 169.31 172.61 177.43 189.35 198.68 212.87 221.46 226.75 233.46 231.53 230.98 232.26 222.26 215.72 210.65 202.24 196.91 193.31
2 184.74 179.70 179.84 173.51 170.73 172.10 173.38 174.79 182.35 189.89 199.04 214.87 222.51 233.57 235.69 232.52 231.62 230.49 226.96 217.09 212.11 205.83 199.47 190.39
3 186.32 183.19 176.84 174.03 174.75 169.70 174.59 177.74 180.28 190.72 202.52 210.90 225.76 227.28 233.34 237.28 232.76 229.58 229.13 215.50 209.13 206.51 196.29 192.16
4 188.66 181.07 176.79 177.82 170.62 170.83 172.09 175.9 181.2 192.33 202.25 214.64 221.21 228.93 237.64 233.38 234.64 233.42 224.67 216.67 213.41 202.43 198.53 194.57
5 185.1 182.3 180.2 174.5 171.5 173.4 174.7 175.3 182.9 191.8 199.9 214.8 223.8 234.4 230.8 234.4 237.3 229.3 224.7 220.4 208.4 204.3 199.8 191.6
6 186.82 183.87 176.77 174.53 174.36 169.07 173.28 174.64 184.09 190.14 203.5 210.9 222.72 231.96 233.5 237.79 231.81 235.91 226.19 219.63 208.68 206.4 196.67 191.35
7 190 180 178 177 171 170 173 178 182 193 203 211 223 229 237 231 235 230 225 220 209 205 200 191
8 186 184 178 175 174 170 176 176 181 192 203 212 225 227 234 238 233 230 229 219 212 203 197 194
9 185 182 179 174 172 173 174 175 183 192 199 215 221 230 236 232 238 233 227 216 212 202 198 194
10 186 181 180 173 172 172 175 176 183 191 200 215 223 229 237 232 234 231 227 215 210 205 198 191
11 189 180 178 176 172 170 172 178 179 189 201 216 220 229 235 238 233 235 226 222 214 204 197 191
12 189 182 181 176 171 173 174 174 183 191 200 214 223 228 234 237 233 233 227 219 209 206 196 192
13 188 181 177 177 170 170 174 175 183 191 202 214 223 233 232 235 235 231 228 218 212 202 201 190
August 14 15 187 188 184 181 176 178 174 176 173 171 170 170 175 172 175 177 185 179 190 190 200 200 215 216 220 220 235 230 234 237 237 233 233 235 229 230 228 227 215 216 210 209 205 206 197 196 192 191
16 189 180 178 177 171 170 175 174 184 191 203 213 222 230 233 238 232 234 226 221 210 202 200 193
17 188 181 177 176 171 169 175 175 183 191 203 211 222 234 231 234 236 232 220 220 209 203 199 191
18 186 184 176 175 174 170 174 177 180 192 202 213 226 228 237 232 231 231 224 219 210 203 200 191
19 186 184 176 174 175 169 176 176 184 190 198 213 225 229 233 236 237 230 223 220 209 204 199 191
20 186 184 176 174 174 169 175 176 180 192 203 213 226 228 234 237 234 229 226 215 210 205 197 192
21 188 181 177 177 170 171 171 179 182 191 201 216 222 230 237 234 233 233 223 217 212 203 196 195
22 185 182 180 174 172 172 173 175 183 192 201 216 223 230 236 233 235 227 229 220 211 203 201 191
23 189 181 177 177 170 171 171 177 182 190 202 215 222 234 231 234 234 232 223 215 213 202 197 195
24 185 182 179 174 172 172 170 176 181 192 203 214 224 236 234 239 233 231 222 216 212 202 197 194
25 186 181 179 173 172 172 171 175 180 192 203 214 226 230 238 231 236 236 219 220 210 205 196 191
26 189 180 178 176 171 170 173 175 183 191 205 215 227 228 234 238 232 228 224 219 209 202 200 190
27 185 184 176 175 174 170 175 176 182 189 204 212 223 233 232 237 234 232 226 219 207 203 199 191
28 185 184 176 173 174 169 175 176 181 192 203 213 227 229 233 239 233 229 226 215 209 205 196 191
29 189 180 177 176 171 170 171 177 185 193 202 218 222 234 231 239 233 229 226 215 209 205 195 191
30 188 180 177 177 171 170 173 175 183 191 204 214 227 232 236 235 236 228 222 220 210 206 195 192
31 189 180 177 177 170 170 173 174 183 191 205 211 223 233 231 236 238 226 223 215 210 204 196 189
7 - RUNNING COST SUMMARY Chiller Option: Yearly Energy Cost: $143,000 VRF Option 1 : Yearly Energy Cost: $85,600 Yearly Energy Cost Reduction For VRF Option 1 Vs Chiller Option:
-57400$ = -40%
Chiller Option: Yearly Energy Cost: $143,000 VRF Option 2 : Yearly Energy Cost: $83,800 Yearly Energy Cost Reduction
For VRF Option 2 Vs Chiller Option:
-59200$ = -42%
8 - MAINTENANCE AND SPARE PARTS Chiller option Yearly Maintenance and Spare part Cost Item
Qty
Maintenance Operation cost /unit
$
Total
Chiller
2
6260
12520
Fresh Air Handling Units
2
680
1361
Chilled Water Pumps
6
410
2460
Fan Coil Units
139
40
5560
Treatment for Water / Chemicals
1
3000
3000
Spare parts
-
Inclusive
$
24901 VRF option Yearly Maintenance and Spare part Cost Item
Qty
Maintenance Operation cost /unit
$
Total
Indoor Units
152
40
6080
Outdoor Units
24
270
6480
Dx Fresh Air Handling Units
2
600
1200
Spare parts
-
Inclusive 13760
$
8 - MAINTENANCE AND SPARE PARTS Reduction in maintenance and spare part yearly Cost of VRF options vs Chiller Option :
$ 24,901
-45%
$ 13,760
9 - LIFE CYCLE COST LCC-P = IC + ESPWF (COST energy + COST maintenance)
Where: ESPWF =
(1+d)n
–1
d(1+d)n
LCC -P
Life-cycle cost Present value
IC
Initial cost of alternative
ESPWF
Equal series present worth factor
COST energy
Yearly energy cost saving
COST maintenance
Yearly maintenance cost reduction
n= lifetime in years and d=discount rate in percent/100
Application: d = 0.08%, n=20 years, ESPWF=9.8
9 - LIFE CYCLE COST Initial Cost
Yearly Energy Cost
Maintenance And Spare Parts Cost
LCC :Present Value
Air Cooled chiller
VRF option 1
$1,109,609
$1,519,000
$143,000
$85,600
$24,901
$13,760
$2,758,086
$2,494,531
VRF Option 1 Life Cycle Cost is lower than Chillers by:
-264,000$ = -10%
9 - LIFE CYCLE COST Initial Cost
Yearly Energy Cost
Maintenance And Spare Parts Cost
LCC :Present Value
Air Cooled chiller
VRF option 2
$1,109,609
$1,437,878
$143,000
$83,800
$24,901
$13,760
$2,758,086
$2,395,736
VRF Option 2 Life Cycle Cost is lower than Chillers by:
-362,000$ = -13%
10 - ANALYSIS A. Technical criteria B. Financial criteria C. Maintenance management criteria
10.A - TECHNICAL ANALYSIS Technical Considerations
Air Cooled Chilled Water
VRF System
System / Partial Load Response
Low, due to Primary and secondary heat exchange circuits.
High, due to Direct expansion
Outdoor Plant Requirement
2 Chillers fit on roof. Area needed=140 m2
Minimum area for one chiller is 75m2. * Covered Pump room area needed=50m2
Option 1: 24 outdoor units on roof. Area needed=260 m2 Option 2: 2 outdoor units in each typical floor. Area needed is 11m2 per floor. Minimum Area per one OU-30Hp is 6.5m2, more Flexibility to fit the outdoor units No need
Fresh Air and Exhaust System
Fresh air handling unit Can be connected to same chiller.
Requires separate DX treated fresh air system.
Distribution System
1 shaft: 1x0.5m2
Option 1:1 shaft: 1.6x1m2 Option 2: No need
10.A - TECHNICAL ANALYSIS (CONT’D) Technical Considerations
Air Cooled Chilled Water
VRF System
* Acoustical and vibration treatment
Acoustical and Vibration system is needed
No need (or minimal)
Water treatment System
Needed
No need
Water Leakage
High risk of damage on finishing materials
No damage
Refrigerant leakage
No limitations
Refrigerant concentration to follow Ashrae limitations.
*Hydronic balancing
Complicated and needs advanced labor skills
No need
Air flow Set point for Indoor units
Three speed fan (FCU) Wide range of fan air speed with multi setting of static No optimization since working point is not easily pressure to meet the required air flow leading to low met. wattage and low noise level
10.A - TECHNICAL ANALYSIS (CONT’D) Technical Considerations
Air Cooled Chilled Water
VRF System
*Metering System for Rental areas and shops in GF.
Required the addition of complete metering system including but not limited to energy meters, sensors, cabling, software and space for installation.
Need Power meter connection to the Controller. Power
Design System
Greater Responsibilities
Easy design system
* Electrical Power, Cable and Distribution system.
630kw For Chillers & Pumps
Option1: 560Kw For OU Relatively Same impact. Option2: 44Kw Per floor Major reduction in cable section/ length and electrical Distribution system
*Items not considered in installation cost but will lead to additional Cost reduction
10.B - FINANCIAL ANALYSIS Financial Considerations
Air Cooled Chilled Water
VRF System Option 1
VRF System Option 2
165
226
213
433
259
254
75
42
42
System
Air Conditioning System Capital Cost per Cooled Area, $/m2 Yearly HVAC Running Cost per TR Yearly HVAC Maintenance Cost per TR
*Residential Tower in Dubai: Average Construction cost is around 2000-2200 $ /m2 depending on building height and standard.
10.C - MAINTENANCE MANAGEMENT Operation Points
Air Cooled Chilled Water Plant
VRF System
Maintenance of outdoor units
2 chillers, 6 pumps, water treatment system to be 24 outdoor units need to be maintained maintained
Maintenance and monitoring of Indoor units
From each AHU/FCU
One single point (outdoor unit) to monitor related indoor units
Life system Spare Parts
20 years More components to go wrong: chiller moving parts, Control valves, sensors…
20 years Less spare parts are needed
Control system Calibration of Metering system for rental areas
Complex system Energy meters need regular calibration
Maintenance for pipes insulation
Highly needed to avoid pipes condensation
Very simple Electronic type (PPD), no need for calibration. minimal
Please contact CEDRO at:
Thank you
T/F: +961-1-981944 E:
[email protected] www.cedro-undp.org Beirut, Maarad Street, Building 287B, 1st floor
cedroundp
cedro_undp
CEDROproject
cedroproject.wordpress.com
