Low-Cost Tweaks Yield Big-Time Savings

Once Jack Dale Associates (JDA) quantified mechanical-system interactions for Texaco's data center, specified techniques were employed to upgrade the plant while avoiding disruptions to data-processing operations. Total construction costs for chiller-plant renovations commissioned by JDA were less than $600,000.

11/01/2000


Once Jack Dale Associates (JDA) quantified mechanical-system interactions for Texaco's data center, specified techniques were employed to upgrade the plant while avoiding disruptions to data-processing operations. Total construction costs for chiller-plant renovations commissioned by JDA were less than $600,000.

Procedures outlined by the engineering team improved energy efficiency and continue to save the petrochemical company more than $100,000 per year in utility costs. The design not only solved operating problems, but also improved the facility's ability to increase its chilled-water reserve for future expansions. Best of all, the upgrades reduced energy consumption. Key features include:

 

The upgrades help set system demand and to ensure that only the required amount of chilled water is distributed.

Before JDA began work on the project, Texaco had received a number of proposals for resolving the facility's system problems. The least onerous of the proposals would have required a two-week shutdown of the entire 5,000-ton chiller plant and over $2 million to complete.

Table 1 - Existing HVAC System Parameters


TimeBypass positionB riser flowB supply tempB return tempMain CHW supply temp FChilled water flow (gpm)Flow to labs (gpm)BAX flow (gpm)East-West riser flow (gpm)Main return header pressure (psi)Main supply header pressure (psi)IBM CDU flow (L/M)

13:00

Closed

1584

44.6

52.7

43.6

2778

414

617

1610

66

65

190

13:15

10% open

1665

44.7

52.1

43.7

2787

426

626

1661

65

64

190

13:20

15% open

1634

44.6

52.1

43.6

2737

432

637

1655

65

65

190

13:30

20% open

1666

45.0

52.0

43.7

2645

505

636

1704

65

65

200

13:38

25% open

1686

45.0

52.1

43.9

2655

504

630

1713

65

66

200

13:43

35% open

1669

44.4

52.3

44.0

2635

504

637

1728

65

66

200

13:49

Full open

1662

44.6

52.7

44.3

2671

502

630

1778

66

67

200

13:57

Full open

1363

44.1

54.5

44.3

2631

513

627

1864

68

68

145

14:08

Full open

1333

43.5

54.1

43.8

2611

517

635

930

69

70

130


Table 2 - Savings from Mechanical Plant Re-engineering


Original designRe-engineered design

HP

kW

HP

kW

Subtotal:

972

611

Subtotal:

223

118

Chiller loads:

2,200

1,760

Chiller loads:

1,600

1,280

Total HP & kW:

3,172

2,371

Total HP & kW:

1,832

1,398

Dead head factor:

0.90

Pump kW saved:

973

Total kW Demand:

2,134 kW

Total kW demand:

1,398

Use factor:

0.80

Use factor:

0.80

Annual pump utility cost:

$235,462

Annual pump utility cost:

$45,530

Added utility cost for new office space:

$79,684

Net annual utility savings after chiller plant renovations:

$110,248


Average cost per kWh: 0.055 $/kWh





Product of the Year
Consulting-Specifying Engineer's Product of the Year (POY) contest is the premier award for new products in the HVAC, fire, electrical, and...
40 Under Forty: Get Recognized
Consulting-Specifying Engineer magazine is dedicated to encouraging and recognizing the most talented young individuals...
MEP Giants Program
The MEP Giants program lists the top mechanical, electrical, plumbing, and fire protection engineering firms in the United States.
September 2018
Power boiler control, Product of the Year, power generation,and integration and interoperability
August 2018
MEP Giants, lighting designs, circuit protection, ventilation systems, and more
July 2018
Integrating electrical and HVAC systems, emerging trends in fire, life safety, ASHRAE 90.4
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
Data Center Design
Data centers, data closets, edge and cloud computing, co-location facilities, and similar topics are among the fastest-changing in the industry.
click me