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Informative Annex L2 – Example Investigation Report

Xxxxxx Headquarters BuildingExisting Building Commissioning Investigation Report

April 26, 2010

Prepared by:

ABC Engineering123 Main StreetAnywhere, AA

Note to readers:

This example Investigation Report is from an actual project. It is provided to help illustrate the overall structure and intent of an Investigation Report and includes most of the content typically found in such a document. However, as this example was created prior to the development of Guideline 0.2, it may not match directly with the sections outlined in Annex L2, “Investigation Report.”

photo of facility

Executive SummaryABC Engineering conducted an existing building commissioning (EBCx) investigation of Xxxxxx’s main office building in Anywhere, AA. The purpose of the EBCx investigation was to identify recommendations that, if implemented, would yield energy and/or non-energy benefits. The EBCx investigation occurred from February to March 2010, and included a review of the facility’s electric usage history, a review of the building construction documents, phone conversations with Xxxxxx staff, and a two-day visit to the facility to observe the facility’s operations and hold further discussions with the staff and the facility’s primary HVAC service contractor.

Sixteen HVAC, lighting, and envelope-related recommendations were identified during the EBCx investigation. Implementation of these recommendations would result in energy and non-energy benefits. The recommendations identified during the investigation are described in detail in this report. Implementation of all of the recommendations is estimated to reduce the annual electric usage of the facility by 180,787 kWh (34% of baseline usage) and $11,058. The total estimated implementation cost of all of the recommendations is $117,500.

The facility’s baseline annual energy use index (EUI) is 18.8 kWh/ft2-yr, or 64 kBtu/ft2-yr – the facility is an all-electric facility. The baseline EnergyStar® performance rating for the facility is 40. Implementing the recommendations described in this report is estimated to increase the EnergyStar® performance rating to 68.

The EBCx process typically continues beyond the investigation phase, to the implementation and hand-off phases. If Xxxxxx would like to implement any of the identified recommendations and move forward with the EBCx process, ABC Engineering would be happy to assist

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Table of ContentsExecutive Summary......................................................................................................................................... i

1. Acknowledgements................................................................................................................................... 3

2. Project Goals............................................................................................................................................ 3

3. Facility Background.................................................................................................................................. 3

3.1. Building Information......................................................................................................................... 3

3.2. Heating, Ventilating, and Air-Conditioning..........................................................................................4

3.3. Central Domestic Hot Water Loop....................................................................................................12

3.4. Interior & Exterior Lighting.............................................................................................................12

3.5. Building Controls 12

3.6. Facility Maintenance....................................................................................................................... 13

4. Facility Energy Use Analysis................................................................................................................... 14

4.1. Utility Billing History......................................................................................................................14

4.2. Facility Energy Performance............................................................................................................17

4.3. Target Energy Performance..............................................................................................................17

5. Findings and Recommendations...............................................................................................................18

5.1. HVAC Recommendations................................................................................................................20

5.2. Envelope Recommendations.............................................................................................................26

5.3. Lighting Recommendations..............................................................................................................27

6. Additional Recommendations................................................................................................................... 28

6.1. Service Contract 28

6.2. Other Recommendations.................................................................................................................. 28

6.3. Future EBCx-related Work...............................................................................................................29

Appendix A: New BAS Requirements........................................................................................................30

Appendix B: EnergyStar® Portfolio Manager Statement of Energy Performance.......................................32

Appendix C: EnergyStar® Target Finder....................................................................................................36

Only HVAC Recommendations are Implemented.......................................................................................37

HVAC & Envelope Recommendations are Implemented......................................................................38

All Recommendations are Implemented...............................................................................................39

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1. AcknowledgementsABC Engineering would like to thank the staff of Xxxxxx, as well as Xxx, for their time and assistance throughout the investigation, especially during the site walk-through.

2. Project GoalsXxxxxx’s goals for the project were:

Conduct a focused Existing Building Commissioning (EBCx) investigation of the facility, consistent with an ASHRAE Level II Energy Audit.

Identify recommendations that, if implemented, would yield energy and/or non-energy benefits.

Achieve an EnergyStar® score of 75 through implementing recommendations with energy benefits.

3. Facility Background

3.1. Building InformationXxxxxx’s main office facility is located near downtown Anywhere, AA, at Xxxx. The facility was originally constructed in 19xx and underwent an addition in 19xx. The building consists of three main sections:

19xx admin / office building (“Office”). This section of the facility is 10,584 sf and consists of the following areas / functions:

o Customer Service

o Member Services

o Accounting

o Board Room

o Offices, Conference Rooms, Mail Room

19xx lunchroom / engineering (“Engineering”). This two-story area is 7,118 sf and is adjacent to the Office section, on the west side. It consists of:

o Lunch room on the ground level (at the same level as the adjacent Office area)

o Engineering area on the upper level

19xx warehouse and crew area building (“Warehouse”). This area is 10,369 sf, is west of and adjacent to Engineering, and includes:

o Warehouse storage area

o Meter repair area

o Crew room and gear drying room

This section was originally constructed in 19xx as just a warehouse area. The crew room, gear drying room, and meter repair area were built out in 19xx.

Figure 1 shows the overall floor plan of the facility:

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Figure 1: Xxxxxx Headquarters Building Floor Plan

The Office and Engineering areas are typically occupied from 7 am to 5 pm Monday through Friday. The Engineering area also sees some occupancy on nights and weekends. The Warehouse sees sporadic occupancy; when this space is occupied, it’s typically between 6:30 am and 4 pm.

3.2. Heating, Ventilating, and Air-ConditioningThe Office, Engineering, crew room, and meter repair rooms are conditioned with air-to-air heat pumps. The location of the main HVAC equipment (heat pumps, rooftop exhaust fans) is shown on the roof plan below in Figure 2, based on a satellite image of the facility. Note that the location of the indoor air handler and outdoor heat pump sections of the Office area heat pumps are also shown on the plan.

Figure 2: Xxxxxx Headquarters Roof Plan

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3.1

3.2

3.2.1 OfficeWhen the Office was originally constructed in 19xx, it was conditioned with a multizone air handling unit located in the mechanical / electrical room on the north side of the building. The multizone unit was removed in 2002 and replaced with eight air-to-air heat pumps. The air handler sections of these heat pumps are located where the multizone unit used to be located (in the mechanical / electrical room), and the outdoor condensing unit sections are located outside on grade, just to the north of the mechanical / electrical room.

Figure 3: Office indoor air handler (Typical of 8) Figure 4: Office outdoor heat pumps (Typical of 8)

Since 20xx, three air-to-air ductless heat pumps have also been installed in the Office building – one in Member Services, one in the General Manager’s office, and one in the server room. The condensing units for these three heat pumps are located on grade near the spaces they serve (the outdoor section for the Member Services heat pump is located near the other eight Office building heat pumps).

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Figure 5: Ductless Heat Pump Unit (Typical of 3)

The most common comfort complaints in the facility relate to the main doors to the Customer Service area, during the wintertime. These doors have pushbutton openers. Customers use these openers often, and during the wintertime, the cold air coming in when the doors are standing open can be objectionable. To minimize the amount of time the doors are open, we recommend investigating if the stand-open time for the doors can be reduced, while still meeting ADA requirements.

3.2.2 EngineeringBoth floors of the Engineering area are conditioned with nine rooftop air-to-air heat pumps located directly over the Engineering area. These heat pumps were installed in 2002, replacing the original 1992 rooftop heat pumps, and have airside economizer control.

Figure 6: Rooftop Heat Pump Unit (Typical of 11)

3.2.3 WarehouseIn the Warehouse, the crew room and repair areas are served by two rooftop air-to-air heat pumps with airside economizer control, installed in 2002.

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The warehouse space is served by electric unit heaters, which are rarely used - power to the unit heaters is shut off except for cold days. The temperature set-points of these unit heaters are controlled by the crew staff.

The drying room is conditioned with two electric wall heaters on the east side of the room, controlled by a wall-mounted thermostat. There is a ceiling exhaust fan in the room, which could draw air from the adjacent crew room to the east under the east door of the drying room. However, this fan is not working, likely due to water from the heavy hose spray in this area. During the EBCx investigation, the space conditions were measured at 80°F and 40% RH.

Figure 7: Drying room electric wall heaters

3.2.4 Air-to-Air Heat PumpsThe facility’s heat pumps are documented in Table 1:

Table 1: Air-to-Air Heat Pump Equipment Schedule

Heat Pump

No.Area(s) Served Location

Supply Fan Motor Power

(HP)

Nominal Cooling

Capacity (tons)

HP-1 Crew room in Warehouse Warehouse roof 1/3 2.5

HP-2 Ground floor corridor in Engineering Engineering roof 1/3 2

HP-3 Ground floor lunchroom in Engineering Engineering roof 1/3 2

HP-4 Ground floor unfinished rooms in Engineering

Engineering roof 1/3 2

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Heat Pump

No.Area(s) Served Location

Supply Fan Motor Power

(HP)

Nominal Cooling

Capacity (tons)

HP-5 Upper floor engineering area in Engineering

Engineering roof 1/3 2.5

HP-6 Upper floor engineering area in Engineering

Engineering roof 1/2 2.5

HP-7 Upper floor office in Engineering Engineering roof 1/3 2

HP-8 Upper floor room in Engineering Engineering roof 1/3 2.5

HP-9 Upper floor office in Engineering Engineering roof 1/3 2

HP-10 Meter repair area in Warehouse Warehouse roof 1/3 2

HP-11 Upper floor office in Engineering Warehouse roof 1/3 2

AH/HP-1 Offices and toilet rooms in northern half of Office

Office mech / elect room

1/3 3

AH/HP-2 Hallway around courtyard in Office Office mech / elect room

1/2 3

AH/HP-3 Mail room, south conference room in Office


1/3 3

AH/HP-4 Offices and meeting room on west side of Office


3/4 6

AH/HP-5 Board room in Office (south half) Office mech / elect room

1/3 3.5

AH/HP-6 Board room in Office (north half) Office mech / elect room

1/3 3

AH/HP-7 Customer service and accounting in Office


1.5 7

AH/HP-8 Member services. Unit is currently shut off.


1/3 3.5

Ductless HP-1

Server room on east side of Office. Is actually an air conditioner (no heat).

Ceiling of server room

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Ductless HP-2

Member services in Office Ceiling of member services

2

Ductless HP-3

General manager’s office in Office Ceiling of office 3

Total 8-1/4 63

The heat pumps are controlled by conventional wall-mounted thermostats. The thermostats are adjustable (the occupants can adjust the set-points up or down by ±2°F) and are non-indicating.

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The set-points can also be monitored and controlled through the existing building automation system (BAS).

Space temperatures were monitored in four areas for five days during the investigation and were found to fall within typically acceptable levels as shown in Figure 8:

Figure 8: Measured space temperatures

3.2.5 Ventilation SystemsVentilation air is delivered to the occupied spaces via the heat pumps. Each rooftop heat pump in the Engineering area has an economizer damper, with a minimum position for minimum outside air delivery. The heat pumps serving the Office area draw minimum outside air through a louver on the north exterior wall of the mechanical / electrical room.

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Figure 9: Office Heat Pump Outdoor Air Intake

As the Member Services heat pump is now served from a ductless heat pump without mechanical ventilation (the ducted heat pump serving this area was disabled after the ductless unit was installed), CO 2

levels were monitored in this space for five days during the investigation, to see if the lack of mechanical ventilation was creating unacceptably high CO2 levels. As shown in Figure 10, the CO2 levels fall below the typical maximum acceptable level, indicating that ventilation is adequate in this space (likely due to this space being open to other mechanically ventilated spaces):

Figure 10: Measured CO2 levels

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Office Heat Pumps Outdoor Air Intake

Closed off Outdoor Air Intake

The outside airflow being drawn in by the Office area heat pumps was spot measured at 620 cfm, which equates to 22 cfm/person. This is above the default office outdoor airflow rate of 17 cfm/person but below the custom calculated ventilation rate of 990 cfm, as calculated using the procedures in ASHRAE Standard 62.1-2010, Ventilation for Acceptable Indoor Air Quality. Since the measured value falls between the default value, and the custom calculated value and the measured CO2 levels fall within acceptable tolerances, the Office area appears to be adequately ventilated.

3.2.6 Exhaust SystemsThe facility uses eight rooftop exhaust fans and five ceiling exhaust fans for various types of exhaust, as outlined in Table 2:

Table 2: Exhaust Fan Equipment Schedule

Exhaust Fan Tag

Exhaust Fan Type Area(s) Served Location

Fan Motor Power (HP)

Type of Control

CEF-1 Ceiling exhaust fan

Drying room Ceiling of room served

Fractional HP

Wall switch. Fan

does not work.


Crew room north shower room

Ceiling of room served

Fractional HP

Occ sensor


Crew room south shower room


Fractional HP

Occ sensor


Foreman area north toilet room


Fractional HP

Wall switch


Foreman area south toilet room


Fractional HP

Wall switch

Engineering Toilet REF

Rooftop exhaust fan

Four toilet rooms on first floor of Engineering

Engineering roof

1/2 HP None (24/7)

Lunch Room REF

Rooftop exhaust fan

Lunch room on the first floor of Engineering

Office roof 1/3 HP Twist timer

Member Services

REF

Rooftop exhaust fan

Member services in Office Office roof 1/2 HP Twist timer

North Office Toilet REF

Rooftop exhaust fan

Toilet rooms on north side of Office

Office roof 1/3 HP None (24/7)

Board Room N REF

Rooftop exhaust fan

North half of Board Room in Office


Board Room S REF

Rooftop exhaust fan

South half of Board Room in Office


Meeting Room REF

Rooftop exhaust fan

Meeting room on west side of Office


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Exhaust Fan Tag

Exhaust Fan Type Area(s) Served Location

Fan Motor Power (HP)

Type of Control

South Office Toilet REF

Rooftop exhaust fan

Toilet rooms on south side of Office

Office roof 1/3 HP None (24/7)

During the EBCx investigation, all of the twist timers were found to be working except for the timer serving the Lunch Room – the staff has said that they will replace this timer.

The staff noted that the toilet rooms on the north side of the ground floor of Engineering (served by Engineering REF) get cold during the wintertime if the exhaust fan is off.

The ceiling exhaust fan in the drying room is not working, likely due to water from the heavy hose spray in this area.

Figure 11: Rooftop exhaust fan

3.3. Central Domestic Hot Water LoopDomestic hot water is delivered to plumbing fixtures throughout the facility via three electric water heaters (one 60 gallon, one 80 gallon, one five gallon). The 60 gallon water heater is located in the janitor’s closet across from the Office area board room and serves the adjacent showers and toilet rooms as well as the board room and member services area sinks. The 80 gallon unit is located in the mezzanine storage area over the Warehouse and serves the engineering area toilet rooms, crew lunch room, crew toilet rooms, crew showers, and inside lunchroom area. The five gallon water heater serves the south toilet rooms in the Office area, next to the General Manager’s office. Each water heater is set at 120°F supply water temperature.

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6.1

3.4. Interior & Exterior LightingLighting was not included in the scope of the EBCx investigation. In general, though, the interior overhead lighting is mostly controlled by motion sensors. There is some display lighting that is kept on for demonstrating lighting technologies to Xxxxxx customers.

The exterior lighting, serving the parking area and the yard area, is controlled by photocells.

3.5. Building ControlsThe building uses a Xxxx BAS for limited monitoring and control of the heat pumps. The control system is 10-15 years old and has limited capability. E.g., the system is not capable of scheduling heat pumps on and off.

The control system does not monitor or control any of the facility’s exhaust fans.

Figure 12: Control system screenshot

3.6. Facility MaintenanceMost maintenance is performed on-site, by in-house staff. An outside service contractor services all the heat pumps in the facility every six months. Based on a conversation with the service contractor, they replace filters quarterly, clean the coils annually, and check the following annually: refrigerant charge, refrigerant valve operation, defrost cycle, electric heat operation. They do not test economizer operation and do not provide a written summary of the work performed each quarter / year.

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4. Facility Energy Use Analysis

4.1. Utility Billing HistoryUtility billing consumption data for 2002 through 2009 was analyzed as part of the facility energy use analysis to interpret facility energy use characteristics and determine the existence of any anomalies.

Figure 13 shows the monthly electric energy use profile of the facility from 2002 through 2009. The figure shows the electricity use during the summer months remains relatively constant from year to year. However, the figure also shows the winter electricity use increasing from 1,555 kWh/day in January, 2003 to 2,315 kWh/day in January, 2009, a 49 percent increase in electricity use for the month of January over the past six years.

Figure 13: Monthly Electricity Use Profile

Analysis of the mean monthly ambient temperatures from 2002 through 2009 indicates the monthly ambient temperature for January decreased from 44.8°F in 2003 to 39.9°F in 2009 (see Figure 14). Based on our calculations, this drop in temperature accounts for the majority of the increase in January (wintertime) usage.

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Figure 14: Outdoor Air Temperature Variation from 2002 through 2009

The utility billing data for the latest annual billing cycle, 2009, was input into an energy profiling program called EZ-SIM to determine estimates of building end-uses. The result of this analysis is shown in Figures 15 and 16 below.

Figure 15: Monthly Building Energy End-Use Analysis Results

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Figure 16: Annual Building Energy End-Use Analysis Results

As shown in Figure 15, there appears to be simultaneous heating and cooling occurring during the winter months (mid-October through mid-March). This may be due to two spaces in the building that have year-round cooling requirements – the data center room in the Office building, and the computer room in the Engineering building.

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4.2. Facility Energy PerformanceThe facility energy use intensity (EUI) and EnergyStar® Performance Rating were determined as part of the facility energy use analysis. The current EUI, based on the 2009 utility billing data, is 64 kBtu/ft2-yr, or 18.8 kWh/ft2-yr. Based on the EnergyStar® Target Score Finder, this energy use corresponds to a performance rating of 40. The EnergyStar® performance rating is a percentile ranking relative to other similar buildings throughout the country, where a rating of 50 is average. A score of 40 means that Xxxxxx Headquarters building is using slightly more energy than other small office / warehouse buildings across the US. The performance rating of 40 also suggests that the building could be performing better, indicating there is potential for energy savings.

4.3. Target Energy PerformanceXxxxxx indicated that they would like to have the headquarters building EnergyStar® Certified. EnergyStar® Certification requires a minimum performance rating of 75. In order to achieve EnergyStar® Certification, the facility EUI would need to be reduced from 64 kBtu/ft2-yr to 43 kBtu/ft2-yr, a 34% reduction in usage. In other words, the energy savings resulting from implementing recommendations would need to be at least 34 percent of the 2009 electric energy use to achieve this rating.

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5. Findings and RecommendationsThroughout the EBCx investigation, sixteen HVAC, envelope, and lighting-related recommendations were identified. These are summarized in the list of findings and recommendations below (Table 3) and discussed in detail in the sections following this table. The supporting calculations for the energy savings and implementation cost estimates listed in the table below are available upon request from ABC Engineering.

Table 3: List of Findings and Recommendations

Recommen-dation No.

Short Description Finding Recommendation Benefits related to Implementing the

Recommendation

Estimated Implementation Cost ($), Simple Payback

Period (yrs)

Recommendations for Ongoing Persistence of Benefits

R1 Heat pump scheduling

All of the heat pumps currently operate continuously. The existing control system does not allow for heat pump on/off scheduling.

Turn off the heat pumps serving the Office area during unoccupied hours. Install a new BAS to accomplish this.

Energy savings, enhanced monitoring of heat pumps and exhaust fans. Estimated annual energy savings of 95,540 kWh, $5,945.

$36,000, 6.1 years. Every quarter, verify that the heat pumps are not operating at night or on weekends.

R2 Toilet room exhaust fan

control

The three large rooftop exhaust fans currently operate continuously.

The two offices adjacent to (south of) the Office north toilet rooms are served by the Office north toilet exhaust fan. They do not need to be served by the exhaust system.

Control the rooftop exhaust fans from motion sensors. Remove the exhaust grilles serving the offices.

Energy savings. Estimated annual energy savings of 4,400 kWh, $264.

$8,800, 33 years. Every quarter, verify that the exhaust fans are not operating at night or on weekends.

R3 Economizer damper control

The economizer systems for the rooftop heat pumps utilize an older style of economizer controller.

Control the economizer dampers on the eleven rooftop heat pumps through the new BAS.

Energy savings, increased ventilation due to increased economizer operation. Estimated annual energy savings of 15,070 kWh, $904.

$39,000, 43 years. Include checks of economizer damper control and performance in the service contractor’s scope of work.

R4 Install economizer on

AH/HP-7

The air handlers / heat pumps serving the Office building do not use airside economizers.

Install an airside economizer system for AH/HP-7 in the Office area. Control through the new BAS.

Energy savings, increased indoor environmental quality due to increased economizer operation (increased ventilation). Estimated annual energy savings of 4,550 kWh, $273.

$6,000, 22 years. Include checks of economizer damper control and performance in the service contractor’s scope of work.

R5 General Manager’s heat

pump

The heat pump serving the General Manager’s office is oversized, creating uncomfortable conditions in the space due to wide temperature swings and noisy unit operation.

Replace the General Manager’s ductless heat pump with a smaller heat pump.

Increased occupant comfort due to more stable space temperature control.

$4,200 None.

R6 Low income office ducting

The low income office is noisy and experiences wide temperature swings.

Reduct the diffuser serving the low income office in the Office area.

Increased occupant comfort due to more stable space temperature control.

$1,000 None.

R7 Drying room exhaust fan

Clothes do not dry as fast as desired in the drying room. The ceiling exhaust fan serving the room does not work.

Replace the ceiling exhaust fan serving the drying room with an inline exhaust fan. Install a humidistat near the existing thermostats, and control the fan from the humidistat.

Increased functionality of the space due to lower humidity levels resulting in more efficient drying.

$1,300 Every quarter, verify that the exhaust fan is still working by increasing the humidity set-point so that the fan turns on.

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Recommen-dation No.

Short Description Finding Recommendation Benefits related to Implementing the

Recommendation

Estimated Implementation Cost ($), Simple Payback

Period (yrs)

Recommendations for Ongoing Persistence of Benefits

R8 Mail room and conference room

temperature control

The thermostat for AH/HP-3 is located in the General Manager’s office. This unit serves this office as well as the mail room and the adjacent conference room. The General Manager’s separate ductless heat pump is influencing performance of AH/HP-3.

Remove the thermostat for AH/HP-3 from the General Manager’s office. Add t’stats in the mail room and adjacent conference room, add a motion sensor in the conference room, and control the unit from these t’stats.

Increased occupant comfort due to more accurate and stable space temperature control.

$2,600 None.

R9 Install and repair wall insulation

Around the Office courtyard, the wall insulation is not installed flush against the metal siding, there are gaps in the wall insulation, and the wall insulation is not secured in place in some locations.

In Office area, install new exterior wall insulation in areas currently uninsulated, repair existing wall insulation where damaged / improperly installed.


$5,000 (rough estimate), 5.9 year

payback.

None.

R10 Increase roof insulation

The insulation installed underneath the roof deck is thin (approximately R-11).

Install additional roof insulation when roof is replaced (future work).


Not calculated – future work.

None.

R11 Parking area lighting

High pressure sodium lighting is used in the parking area.

Replace the six 200W high pressure sodium parking area lighting fixtures with LED fixtures.


Not calculated (out of study scope).

None.

R12 Yard area lighting

High wattage lighting fixtures are used in the yard area.

Replace the fourteen 400W yard area lighting fixtures with LED fixtures.

Energy savings. Estimated annual energy savings of 16,800 kWh, $1,008.


None.

R13 Daylighting in Engineering

area

The perimeter areas in the Engineering area have a large amount of window area, yet the lights are on at 100% whenever switched on.

Install daylight sensors to control the ceiling lighting fixtures in the perimeter spaces in the Engineering areas.

Energy savings. Estimated annual energy savings of 202 kWh, $12.


Every quarter, test the operation of the daylighting system through functional testing.

R14 Lighting fixture retrofit

The overhead lights in the Office and Engineering area use 32W 3,500K T8 lamps.

Replace 32W 3,500K T8 lamps in ceiling fixtures with 25W 5,000K full spectrum T8 lamps.

Energy savings, increased occupant comfort (better light quality). Estimated annual energy savings of 14,103 kWh, $846.


None.

R15 Lighting control The overhead lights in the Office and Engineering area are manually controlled.

Monitor lighting operation through the BAS. Add lighting sweep control to BAS. Requires implementation of R1.

Enhanced monitoring of lighting system. $13,600 None.

R16 Accent lighting control

The accent lighting is on at 100% level whenever switched on.

Use motion sensors to turn off interior accent lighting when not needed.



Every quarter, test the operation of the motion sensors through functional testing.

Total Implementation of All ECMs described 180,787 kWh, $11,058 estimated annual energy savings.

$117,500 estimated implementation cost, 10.6 year estimated

simple payback.

The estimated savings values and implementation costs shown in this table are based on engineering calculations. Actual savings and cost values may be slightly different than these. Also note that many of these recommendations have significant non-energy benefits, which have not been quantified but are listed in the table above.

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5.1. HVAC RecommendationsFor the estimated savings values and implementation costs related to these recommendations, see Table 3.

5.1.1 R1 – Heat Pump SchedulingIdentified Finding

During the EBCx investigation, ABC Engineering and Xxxxxx noted that all of the heat pumps currently operate continuously (24/7). Xxxxxx indicated that their operating schedule could be reduced, especially in the Office area. However, the existing control system does not allow for heat pump on/off scheduling.

Recommendation & Benefits

Replace the current control system with a BAS that will allow for heat pump scheduling, as well as monitoring and operation of other equipment in the facility. Since the Office heat pumps share a common return, backdraft dampers will need to be installed on the discharge of these air handlers to avoid backflow in units that are scheduled off.

The new BAS should be Windows 7-based and web accessible with a graphical user interface and have sufficient trending and alarming capability. The new wall-mounted temperature sensors will have pushbutton overrides to allow occupants to operate the units after hours. See Appendix A for more details on the new BAS.

If the Office heat pumps are scheduled off, we recommend implementing night setback / setup temperatures rather than shutting the units off completely. E.g., the setback / setup temperature set-points could be 60°F and 80°F, respectively. We estimate that the heat pumps could bring the spaces back to their occupied set-points within one hour of changing from unoccupied to occupied operation.

Alternate Recommendation

Instead of replacing the Xxxx control system with a new BAS, a lower cost solution would be to replace the existing heat pump thermostats with simple programmable thermostats. Heat pump operating schedules could then be programmed into the thermostats. Global control of heat pump temperature set-points and operating schedules from the Xxxx system would likely not be possible with this option.

5.1.2. R2 – Exhaust Fan ControlIdentified Finding

The three large rooftop exhaust fans (Engineering REF, North Office REF, and South Office REF) currently operate continuously (24/7), even though the building is not occupied continuously.

The two offices adjacent to (south of) the Office north toilet rooms are served by the Office north toilet exhaust fan. These ceiling exhaust grilles are noisy, and these spaces do not need to be served by the exhaust system. At one time, these spaces may have been storage rooms.


For the Office north toilet rooms, add start/stop control of the exhaust fan serving these rooms. Add motion sensors in the two toilet rooms (men’s and women’s), the men’s shower room, and the women’s lounge. Control the lighting of each room from its respective sensor. Keep the lights on for ten minutes after the rooms are unoccupied (length of time easily adjustable by maintenance staff). For the exhaust fan control, if any of the two toilet rooms, shower room, or women’s lounge is occupied (as sensed by the motion sensors), the Office north toilet room exhaust fan turns on and remains on until five minutes after

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these rooms are unoccupied (length of time easily adjustable by maintenance staff). If R1 is implemented, monitor operation of this exhaust fan through the BAS (current transducer). The CT should also allow for generation of an alarm if the exhaust fan belt breaks.

For the Office south toilet rooms, add a motion sensor to the General Manager’s toilet room. Control the fan from this sensor as well as the other two existing motion sensors in the nearby toilet rooms. For the exhaust fan control, if any of the three toilet rooms is occupied (as sensed by the motion sensors), the Office south toilet room exhaust fan turns on and remains on until five minutes after these rooms are unoccupied (length of time easily adjustable by maintenance staff). If R1 is implemented, monitor operation of this exhaust fan through the BAS (current transducer). The CT should also allow for generation of an alarm if the exhaust fan belt breaks.

For the Engineering north toilet rooms, add start/stop control of the exhaust fan serving these rooms. If any of the four rooms is occupied (as sensed by the existing motion sensors), the Engineering north toilet room exhaust fan turns on and remains on until five minutes after the rooms are unoccupied (length of time easily adjustable by maintenance staff). Also install a wall-mounted temperature sensor in the west toilet room of this bank of four toilet rooms. Turn on the exhaust fan if the space temperature drops below 65°F (‘on’ temperature set-point easily adjustable by maintenance staff), and turn it off when the space temperature reaches 2°F above the set-point. If R1 is implemented, monitor operation of this exhaust fan through the BAS (current transducer). The CT should also allow for generation of an alarm if the exhaust fan belt breaks.

Remove the two exhaust grilles serving the offices to the south of the Office north toilet rooms (labeled ‘Office’ in Figure 1) and replace with ceiling tiles. Return air from these offices will pass through either the open office doors or under the doors when they are closed.

5.1.3. R3 – Upgrade Economizer ControlIdentified Finding

The airside economizer systems for the rooftop heat pumps utilize an older style of economizer controller. This controller has a wide deadband, resulting in reduced energy savings related to economizer operation.


If R1 is implemented and a new BAS is installed, upgrade the heat pump control to allow the BAS to control the rooftop heat pumps. With this arrangement, energy savings would be realized since BAS control of the economizers would result in more efficient operation due to the narrower deadband and higher economizer lockout temperature.

5.1.4. R4 – Add Economizer to AH/HP-7Identified Finding

The air handlers / heat pumps serving the Office building do not use airside economizers – minimum outside air is drawn in to deliver ventilation air to the Office building. Adding economizer dampers would result in energy savings by reducing the load on the compressors when in cooling mode.


Adding economizer functionality to each of the air handlers serving the Office area would be difficult and costly, since the units share a common return duct and space is somewhat tight for additional ducting / dampers. However, economizer dampers can be added relatively easily to the largest of the air handlers, AH/HP-7. This unit has a cooling capacity of 7-1/2 tons and an estimated supply airflow of 3,000 cfm.

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There are two 44”w x 69”h louvers in the north exterior wall of the Office mechanical / electrical room. Only one is being used for minimum outside air for the air handlers. The other can be used for adding economizer functionality for AH/HP-7. The work related to this measure includes:

Install a 42”w x 12”h duct between the unused louver in the mechanical / electrical room and the 30” x 30” (field verify) mixed air duct serving AH/HP-7 and AH/HP-8. The latter unit is currently off – there are no plans to turn this unit back on, as the area it serves, Member Services, is being conditioned with a ductless heat pump – so the economizer would effectively be serving AH/HP-7 only.

Install a motorized damper in this new duct. Also install a motorized damper in the existing 30” x 30” duct (field verify), just upstream of where it connects to AH/HP-7.

Remove the controller for AH/HP-7 and take over control through the BAS. Enable the economizer (open the outside air damper, close the mixed air damper) whenever there is a call for cooling and the outside air temperature is less than the return air temperature. During times when the unit is operating and economizer cooling is not being called for, close the outside air damper and open the mixed air damper.

Note that implementation of R1 would be required for this measure to be implemented.

Figure 17: Sketch of Proposed Outdoor Air Intake Duct & Motorized Return Air Damper to AH/HP-7

5.1.5. R5 – Replace GM’s Ductless Heat PumpIdentified Finding

The General Manager’s office is conditioned using a three-ton ductless heat pump unit installed below the ceiling on the south side of the room. When this unit operates in heating and cooling mode, it creates uncomfortable conditions in the space due to the wide temperature swings and noisy unit operation. The unit appears to be oversized.

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Figure 18: GM's Office Ductless Heat Pump Unit


Replace the unit with a properly sized unit (estimated at 1-1/2 tons, verify with an HVAC engineer).

5.1.6. R6 – Reduct Low Income OfficeIdentified Finding

The low income office on the northeast side of Customer Service is noisy and experiences wide temperature swings. The primary occupant of this space, Helen, reports cold temperatures in the space during the summertime, indicating that there may be too much supply air being delivered to the space. This space was originally a storage area, which may be why space conditions are uncomfortable. A variety of HVAC systems serve this space:

A supply air diffuser from the same system that serves the Customer Service area (AH/HP-7). The thermostat for this unit is in the Customer Service area.

A wall-mounted electric heater located high on the south wall of the office, controlled by a thermostat on the north wall of the office.

A ceiling exhaust fan, controlled by a twist timer on the north wall of the office.

Most of the noise in the room is coming from the supply air system. The diffuser serving the space taps directly into the bottom of the main duct serving the Customer Service area, as shown in Figure 19:

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Figure 19: Supply duct serving office


Reduct the supply air diffuser serving the space as follows:

Move the supply diffuser one tile to the west.

Remove the fitting on the bottom of the main duct, and patch the main duct.

Take the existing fitting, and tap into the west side of the main duct approximately 6’ to the north of the supply diffuser. Attach a 90 deg elbow onto the fitting, and duct to the diffuser using 10” diameter flexible ductwork.

Balance the diffuser to 100 cfm.

A longer term solution for this space would be to install a separate HVAC system dedicated to serve this space, since it is a separate thermal zone from the Customer Service area. Perhaps a ductless heat pump system could be used, but adequate ventilation air would need to be ensured with this type of system.

Implementation Update

Since this recommendation was originally identified, the Owner has implemented the measure. However, rather than moving the diffuser one tile to the west, they reused an abandoned diffuser and located it in the northeast corner of the room. The Owner has reported that temperatures are now more stable in the office.

5.1.7. R7 – Control Drying Room from HumidistatIdentified Finding

Clothes do not dry as fast as desired in the drying room. The ceiling exhaust fan serving the room, on the west end of the drying room, does not work, likely due to water from the heavy hose spray that occurs in this area. During the EBCx investigation, the space conditions were measured at 80°F and 40% RH.

Recommendation & Benefits25

Remove the ceiling exhaust fan, and replace it with an intake grille. In the existing duct between the grille and the wall cap on the south end of the building, install an inline exhaust fan that is rated for operating in wet (humid) conditions. Install an access hatch on the floor above to access this fan.

Install a humidistat near the existing thermostats in the drying room. Operate the exhaust fan to maintain a humidity level of 35% in the space (humidity set-point adjustable at humidistat).

Implementation Update

Since this recommendation was originally identified, the Owner has implemented the measure. However, rather than installing a new fan and humidistat, they replaced the burned out motor in the fan, installed a metal shield to protect the motor from water spray, and reused an existing humidistat to control the fan. The crew that uses the drying room have reported that conditions are now more satisfactory (i.e., drier).

5.1.8. R8 – Relocate Thermostat for AH/HP-3Identified Finding

The thermostat for AH/HP-3 is located in the General Manager’s office. This unit serves this office as well as the mail room and the adjacent conference room. However, the General Manager’s office is served by a separate ductless heat pump, which could be influencing the performance of AH/HP-3.


To increase the comfort level in the mail room, move the thermostat from the General Manager’s office to the mail room (near the mail room door). The General Manager’s office will continue to be conditioned by its ductless heat pump.

Also add a thermostat and a motion sensor in the adjacent conference room, near the conference room door. Control AH/HP-3 from the mail room thermostat unless occupancy is sensed in the conference room by the motion sensor. In this case, control the AH/HP from the conference room thermostat. Once occupancy is no longer sensed in the conference room, revert control of the unit back to the mail room thermostat.

5.1.9. Other Recommendations InvestigatedRooftop Heat Pump Economizer Dampers

During the EBCx investigation, all of the eleven rooftop heat pump economizers were tested – at an outside air temperature of 54°F, each of the units were put into cooling mode. If the first stage of cooling turned on the compressor without opening the economizer dampers first, the unit failed the economizer test. If the economizer dampers opened and the compressor stayed off, the unit passed. The following economizers failed the test, and are thus not operating correctly: HP-1, HP-2, HP-3, HP-4, HP-6, & HP-10.

However, with these types of economizer controllers, the units will likely never go into economizer operation since by the time the outside air rises to a point where cooling would be required (calculated at 60°F outside air temperature for this facility), it will be too warm for economizer operation. Repairing or replacing these economizer controllers would result in little, if any, energy savings. However, implementing R3, where control of the units is taken over by the BAS, would result in energy savings related to enhanced economizer operation.

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5.2. Envelope RecommendationsFor the estimated savings values and implementation costs related to these recommendations, see Table 3 above.

5.2.1. R9 – Add Exterior Wall Insulation to Office AreaIdentified Finding

According to Xxxxxx staff, AH/HP-2 serving the hallway around the courtyard operates more often in heating and cooling mode than the other units, likely due to identified issues related to the exterior wall construction above the level of the ceiling.

Around the Office courtyard, a few issues were noted related to the exterior wall batt insulation above the level of the ceiling:

The insulation is not installed flush against the metal siding

There is a large gap between the ceiling and the bottom of the insulation, greatly reducing the effectiveness of the insulation

The insulation is not secured in place in many locations.

Figure 20: Exterior Wall Batt Insulation Not Secured In Place

In addition, around the perimeter of the Office building, ABC Engineering and Xxxxxx staff noted numerous short circuits in the exterior wall insulation above the level of the ceiling.

During a cold day last winter, the staff measured 33°F temperature above the ceiling when it was 29°F outside (66°F in the space). ABC Engineering measured 68°F above the ceiling (72°F in the space) when it was 56°F outside, indicating that there are issues with the exterior wall insulation.

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at columns

Figure 21: Short Circuits in Exterior Wall Batt Insulation Above Ceiling


While the issue has been identified, a specific solution has not yet been determined. ABC Engineering recommends that Xxxxxx work with exterior wall construction specialists in determining a workable solution.

One option that was discussed to remedy this issue includes removing the metal siding, installing rigid insulation, and then reinstalling the metal siding.

5.2.2. R10 – Add Roof Insulation to Office AreaIdentified Finding

The batt insulation installed underneath the roof deck is quite thin (approximately R-11), compared to modern construction standards of approximately R-30. In addition, the insulation appears to be compromised where the deck meets the roof joists.


Add insulation to the roof. We recommend doing this when the roof is replaced next, as this is a high cost measure with a relatively long payback period. Implementation costs for this recommendation were not estimated, since this work likely won’t take place for many years.

5.3. Lighting RecommendationsEven though lighting was not included in the scope of the EBCx investigation, some lighting recommendations were identified. Implementation of these recommendations would further lower the energy use of the facility, increasing the facility’s EnergyStar® score even further. These recommendations are described in Table 3 above.

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at columns

Insulation does not extend to ceiling

Short circuits at columns

6. Additional Recommendations

6.1. Service ContractDuring the EBCx investigation, ABC Engineering noted one other opportunity for optimizing operations at the facility. The current heat pump service contract is more of a deferred maintenance strategy (fix it when the service contractor notices it’s broken), rather than a preventive maintenance strategy (take steps to extend equipment life and minimize the chance of failure). Also, the service contractor does not provide a written summary of the work they perform on site during each service call.

We recommend that Xxxxxx consider revising the service contract to one that:

Includes more preventive maintenance items.

Requires the service contractor to provide written reports on specific work performed during each visit.

Includes operational checks such as economizer damper performance.

6.2. Other RecommendationsThree other recommendations were noted during the on-site investigation and during post-site visit discussions. These recommendations were not analyzed in detail for the reasons outlined below.

6.2.1. Heat Pump ZoningThe cooling capacity of the 22 heat pumps serving the facility totals 63 tons. At 17,487 sf conditioned area, this equates to 278 sf / ton. For this type of facility, we would expect that an installed cooling capacity of 500 sf / ton (35 tons) would be sufficient, suggesting that the existing heat pumps may be oversized. If the heat pumps are indeed oversized at Xxxxxx, the effect would be greater than necessary energy use due to lower equipment efficiency at part load performance and more fans operating than needed.

If Xxxxxx is interested in further investigating this recommendation, we recommend hiring an HVAC designer to investigate the heat pump zoning and look for opportunities to shut off units and reduct from the other units. This recommendation requires a more in-depth analysis than that covered by this EBCx investigation.

6.2.2. Heat Pump Water HeatersEnergy usage related to domestic water heating could be reduced by replacing one or more of the existing tank-type electric water heaters with a heat pump water heater. Heat pump water heaters are most effective when their waste cooling can be rejected to spaces that have a constant cooling load, rather than just rejected to the outdoors.

One location that may make sense for installation of a heat pump water heater is in the computer room adjacent to the board room in the Office, as this space likely has a constant cooling load. The cooling load on the ductless heat pump serving the computer room would be reduced due to the waste cooling from the heat pump water heater being rejected to the same space.

To achieve this, the 60 gallon water heater in the janitor’s closet adjacent to the board room could be removed and replaced with a heat pump water heater located in the computer room. The heat pump water heater would need to be installed in a manner that will not cause a potential water hazard for the computer equipment.

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To estimate the energy savings related to this recommendation, we would recommend monitoring the electric usage of the 60 gallon water heater and working with a local heat pump water heater rep to estimate the costs and savings related to installing a heat pump water heater.

6.2.3. Reduce Simultaneous Heating and CoolingSome heat pumps serve spaces that are connected to spaces served by other heat pumps. For example, there are two heat pumps that serve the board room. Also, the space served by the courtyard heat pump freely communicates with the adjacent member services area and the customer service area. For heat pumps that serve spaces that freely communicate, the space temperature set-points should be set the same to minimize simultaneous heating and cooling.

This recommendation would be easiest to implement if recommendation R1 (new BAS) were implemented – space temperature set-points could be monitored and/or set to minimize simultaneous heating and cooling. Energy savings related to this recommendation is difficult to estimate since it depends highly on occupant behaviors.

6.3. Future EBCx-related WorkThe EBCx process typically continues beyond the investigation phase, to the implementation and hand-off phases. ABC Engineering would be happy to assist Xxxxxx if the project moves into these phases. ABC Engineering could assist by:

1. Conducting a more detailed investigation into Xxxxxx’s lighting systems.

2. Verifying proper implementation of any implemented recommendations.

3. Conducting building operator and service contractor training on the implemented recommendations.

4. Developing a systems manual. A systems manual is a composite document that includes operation manuals, maintenance manuals, and additional information of use to the Owner such as operating requirements (temperatures, hours of operation), equipment lists, and training records.

5. Develop a request for proposal (RFP) for an updated service contract. See 6.1 above for more information about the updated service contract.

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Appendix A: New BAS RequirementsThis section provides a summary of Xxxxxx’s desired functionality for a new building automation system (BAS).

The new BAS shall include a new front end on the existing operator workstation (Roy’s computer). Front end shall be Windows 7-based and shall have:

Trending capability Alarming capability Web accessibility Graphical user interface (GUI), defined by Owner.

The new control panel can be located where existing control panel is located (in main electrical room).

Replace existing space temperature sensors with new sensors. The new sensors will have:

Indicating or non-indicating temperature (as defined by Owner for each zone) Temperature set-point adjustability by occupant Pushbutton override.

The range of set-point adjustability and length of override will be adjustable at the GUI for each sensor / heat pump.

The new BAS will control operation of all heat pumps (eleven rooftop heat pumps, eight indoor heat pumps):

Schedule-based occupied mode: evaporator fan on, unit operates in heating / cooling / economizer modes to maintain space temperature set-pointo Economizer mode applies to rooftop heat pumps only and AH/HP-7 if R4 is implemented.

Schedule-based unoccupied mode: unit is off unless space temp is lower than night setback temp or greater than night setup temp.

Heating and cooling set-points adjustable at GUI, for both occupied and unoccupied (setback / setup) modes of operation

Manual override capability of scheduled operating mode from GUI.

Monitor operation of heat pumps:

Evaporator (supply) fan operation (current transducer) Compressor operation (current transducer) Zone space temperature Discharge air temperature Outside air damper position (economizer operation) – this one applies only to the rooftop heat pumps

and AH/HP-7 if R4 is implemented. Monitor damper position with end switch.

Monitor OA temperature.

Monitor operation of the eight rooftop exhaust fans:

Fan on/off (CT) Belt break (CT).

The BAS shall have sufficient capacity for expansion (allow for add’l 50% of points controlled / monitored with new system).

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Appendix B: EnergyStar® Portfolio Manager Statement of Energy Performance

The facility space use, historic utility data, and other general information (building age, gross floor area, etc.), was entered into EnergyStar® Portfolio Manager to determine the current (baseline) performance rating, which is 40/100 based on December 2009 utility data. An Energy Performance Rating of 40 means that Xxxxxx uses slightly more energy than similar buildings (50 is average). This portfolio was created by ABC Engineering on behalf of Xxxxxx so they may track their headquarter building’s performance after recommendations have been implemented. Entering the facility information into EnergyStar®

Portfolio Manager is a required step in order for the facility to achieve EnergyStar ® Certification. The login information to access this portfolio is as follows:

Website: https://www.energystar.gov/istar/pmpam/index.cfm?fuseaction=login.Login

Username: Xxxxxx

Password: Xxxxxx

The next three pages show the Statement of Performance generated using EnergyStar® Portfolio Manager. These three pages show the current EUI (site and source), greenhouse gas (GHG) emissions, facility space use summary, and current EnergyStar® performance rating as compared to the national average and required EnergyStar® Certified performance ratings.

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https://www.energystar.gov/istar/pmpam/index.cfm?fuseaction=login.Login

Appendix C: EnergyStar® Target FinderEnergyStar® Target Finder was used to estimate what the EnergyStar® performance rating would be if the recommendations were to be implemented. This page and the next two pages show the Target Finder output for three cases: (1) Only HVAC recommendations are implemented; (2) HVAC and envelope recommendations are implemented; (3) All recommendations are implemented. As indicated, the EnergyStar® performance rating increases from 40 to 55 by implementing the HVAC recommendations, from 55 to 58 by also implementing the envelope recommendations, and from 58 to 64 by also implementing the lighting recommendations.

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Only HVAC Recommendations are Implemented

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HVAC & Envelope Recommendations are Implemented

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All Recommendations are Implemented

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