bowie state university fine and performing arts...

Bowie State university fine and performing arts center

Thesis Proposal

Zack Lippert – Mechanical

Advisor: Steve Treado

Location: Bowie, MD

ContentsExecutive Summary....................................................................................................................... 2

Building and Mechanical Overview................................................................................................2

Mechanical Systems Redesign Overview.......................................................................................4

Alternatives Considered.................................................................................................................4

Ground Source Heat Pump....................................................................................................4

Large Diameter Ceiling Fans...................................................................................................5

Underfloor Air Distribution....................................................................................................6

Proposed System Alternatives.......................................................................................................7

Breadth Topics...............................................................................................................................8

Lighting Breadth.....................................................................................................................8

Construction Breadth.............................................................................................................8

Tools and Methods for Analysis.....................................................................................................8

References..................................................................................................................................... 9

Appendix A: Spring Schedule.......................................................................................................10

BSU Fine and Performing Arts Center 10/22/2011 Zack Lippert

Executive SummaryThe Bowie State University Fine and Performing Arts Center is a 123,000 square foot

educational building that has several very different types of spaces. The building is conditioned through a variable air volume system served by 16 air handling units. It has just been completed and will be fully operational starting in the spring semester. The mechanical system uses a chiller and two boilers to meet the heating and cooling loads.

Alternative design approaches have been researched to find a way to reduce the amount of energy that the mechanical system uses to condition the building. The ideas researched were ground source heat pumps, large diameter fans for high volume spaces and underfloor air distribution. After weighing the pros and cons, the underfloor air distribution systems and ground source heat pump were selected for further investigation.

The building contains several spaces with high ceilings and the current system wastes energy by conditioning the entire space despite the fact that the occupants are only on in the lower five to seven feet. The underfloor air distribution will reduce the energy cost by allowing the supply air to be provided at a higher temperature, therefore reducing the amount of cooling needed to treat the air.

The ground source heat pump will reduce the size of the chiller and boilers or perhaps even eliminate the need for them completely. The building has a good amount of unused land surrounding it which could be used for the numerous bore holes that are needed for the system. The only energy required to run the system is the electricity to run the pumps which is significantly less than the energy used by chillers and boilers.

In another attempt to save energy in the building a lighting redesign will be done. It will incorporate energy efficient lamps and ballasts, as well as smart controls such as occupancy sensors and day light sensors. Since all of these redesigns will increase the complexity of the building, the testing and commissioning plan will need to be altered to accommodate the added components. In addition to adding these systems to the commissioning plan the existing plan will be analyzed to see if it can be simplified.

Building and Mechanical OverviewBowie State University’s new Fine and Performing Arts Center is a 123,000 square foot

mixed use building that contains a 400 and 200-seat theatre, a recital hall, class rooms, offices, an art gallery, a large atrium and workshops for creating scenery and costumes. The north side of the building has a large expanse of glass with different colored panes spaced in a pattern to look like sheet music. The numerous acoustical considerations have made this a wonderful


building to enjoy musical and theatrical performances. Figure 1 shows the layout of the building. The north section, highlighted in blue, is three stories filled with classrooms and administrative offices. The south section, highlighted in red, houses the large performance spaces.

Figure 1: Building Layout

There are 3 MAUs with enthalpy wheels that provide ventilation air to the 16 AHUs, which provide conditioned air to the building through VAV systems. There are two 1,712 MBH gas-fired boilers and one 305 ton air cooled chiller on site. Tables 1 and 2 show the size and the area that each AHU and MAU serves.

Unit Area Served Min OA (CFM)

Enthalpy Wheel

MAU-1 AHUs-1, 3, 9 9500 YesMAU-2 AHUs-2, 7, 10, 14 9030 YesMAU-3 AHUs-8, 11, 12 17400 Yes

Table 1: Mixed Air Units


Unit Area Served CFM Min OA (CFM)

Enthalpy Wheel

AHU-1 Main Theater 7000 4000 NoAHU-2 Recital Hall 4850 3700 NoAHU-3 Main Stage 3750 2900 NoAHU-4 Black Box Theater 6200 3500 YesAHU-5 Movement Studio 4200 1800 NoAHU-6 Choral Room 1950 900 NoAHU-7 Instrument Ensemble 2700 2700 NoAHU-8 Art Gallery 4500 2900 NoAHU-9 2nd Floor, East 6185 2600 No

AHU-10 2nd Floor, Lobby & Lounge 5500 2250 NoAHU-11 North Wing 1st Floor 9300 4000 NoAHU-12 North Wing 2nd & 3rd Floor 19800 10500 NoAHU-13 West Offices 1900 475 NoAHU-14 Instructional Offices 800 380 NoAHU-15 1st Floor Electrical Room 1600 30 NoAHU-16 3rd Floor Electrical Room 1700 0 No

Table 2: Air Handling Units

Mechanical Systems Redesign OverviewThe current system in place at the BSU Fine and Performing Arts Center uses 585,000

kWh of electricity and 736,000 kBtu per year based on the energy model created for Tech 2. This amount of energy usage costs the university almost $135,000 each year. The focus of this redesign is to reduce the amount of energy that the building consumes. With the aim of reducing energy in the mechanical system, the following alternatives were considered: a ground source heat pump, large diameter ceiling fans and an underfloor air distribution system.

Alternatives Considered

Ground Source Heat PumpA vertical loop ground source heat pump (GSHP) was considered in order to reduce the

amount of energy used by the mechanical system. The system can be used in both heating and cooling seasons and would allow the existing mechanical systems to be reduced in size and cost. The vertical loop GSHPs have several advantages over the horizontal loops. They need less land to operate, the deeper bore holes allow the pipes to be in contact with a more constant temperature soil throughout the year, it uses less piping than horizontal layouts, and has a


more efficient system performance. The drawbacks to the vertical loop layout is that it has a higher installation cost because of all the specialized equipment needed to drill the deep bore holes and the there are fewer contractors that can due the work.

Figure 2: Vertical Loop GSHP (McQuay)

Figure 2 shows a diagram of a vertical loop GSHP. The vertical loop GSHP runs deep enough in the earth that the temperature is a constant 55°F throughout the year. GSHPs require a lot of space in order to reject or absorb enough heat for the building. The vertical loop system needs approximately 250 to 300 sf/ton. The red shapes in figure 3 show possible locations near the building that could be used for the vertical loops.

Figure 3: Aerial View of Site

(Image courtesy of Google Maps)


Large Diameter Ceiling FansLarge diameter low revolution ceiling fans were considered for the large atrium space.

Any large space is going to have stratification, meaning the heat is wasted in the area that no one occupies. Ceiling fans are able to push that hot air back down to where the occupants are requiring less energy be used to heat the space. Figure 4 shows the benefit of mixing the air in areas with high ceilings. Also, during the summer months the fans provide a gentle breeze to increase evaporative cooling. This would allow the spaces to be several degrees warmer while the occupants still feel comfortable.

Figure 4: Stratification in High Volume Spaces (Summer)

Underfloor Air DistributionAn underfloor air distribution (UFAD) was considered for the large performance spaces

in the south section of the building. There are seven large performance spaces with ceilings ranging from 20 to 50 feet. The current system has overhead diffusers in the ceiling that condition the entire space. The UFAD system would provide the conditioned air directly to where the occupants are which would require less conditioning of the air. Figure 5 shows the benefit of underfloor air distribution.


Figure 5: Benefit of UFAD (Hamilton)

Proposed System AlternativesIn order to reduce the amount of energy that the mechanical system uses, an underfloor

air distribution and a vertical loop ground source heat pump have been proposed.

The UFAD system will allow the occupants of the large volume spaces such as the theaters and dance studios to be more comfortable and the systems can provide higher temperature air to the spaces. Since the air needs to be warmer to keep the occupants comfortable the mechanical system can save energy on conditioning the air for these spaces. Also, since the air reaches the occupants first, the heat generated by the lighting and other electrical equipment will have less effect on the space. The initial cost for the UFAD system will be significantly higher because the floors will all need to be raised to allow for the air distribution. An analysis will be done to see if the energy savings from the reduced fan power and higher supply air temperatures are enough to offset the increased initial cost.

The GSHP will reduce the amount of energy that the chiller and boilers need to condition the building. Depending on the size of the GSHP system, it could replace the chiller and boilers altogether. The GSHP requires a lot of nearby land to reject and absorb heat from the ground. The vertical loop proposed requires 250 to 300 sf/ton. The site has plenty of unused land surrounding the building which could be used for the GSHP as shown in Figure 3.


The GSHP will significantly increase the upfront cost of the project but using it for both cooling and heating will greatly reduce the monthly utilities cost for both electricity and natural gas.

Breadth Topics

Lighting BreadthThe energy model created in tech 2 showed that over half of the electricity consumption

in the building is from lighting. The lighting system for the north section of the building will be redesigned with an emphasis on energy efficiency. The south section will be omitted from the redesign because the performance spaces need special lighting for artistic and aesthetical reasons. The redesign will use energy efficient lamps, ballasts, occupancy sensors and daylight sensors. After the design is done, an energy model will be created to determine if the payback period is acceptable.

Construction Breadth The addition of the underfloor air distribution system and ground source heat pump

will greatly affect the testing and commissioning of the building. As a construction breadth a plan for testing and commissioning these systems will be created. Also, the existing testing and commissioning requirements will be looked at to see if they can be simplified.

Tools and Methods for AnalysisAn accurate design and implementation will be achieved for both depths and breadth by

researching all of the equipment and systems in great detail. Also, the use of numerous design software such as Revit Mechanical, Trane Trace, AGI32, DAYSIM, Excel and Microsoft Project.

Revit Mechanical and Trane Trace will be used to model the underfloor air distribution system. Revit will be used to model the system for duct and pipe sizing. Trane Trace will be used to model the energy consumed by the new system. It will then be used to compare the energy used by existing system to the energy of the proposed system.

Trane Trace will be used again for the GSHP. It will be used to determine the amount of energy the system can replace from the existing system. It will also be used to estimate the remaining loads that the chiller and boiler would need to meet. For sizing the GSHP I will use the ASHRAE Handbook 2007 Applications.

The lighting redesign will use AGI32 to calculate the amount of light on each surface in the rooms and the amount of energy used for the lighting. DAYSIM will be used to calculate the amount of light entering the rooms and how much artificial light would be needed to meet the


requirements of the rooms. The commissioning and testing redesign will use Microsoft Project to recreate the testing and commissioning schedule.

ConclusionThe intent of this redesign is to significantly reduce the amount of energy used by the

building and decrease the impact of the building on the environment. The ground source heat pump and underfloor air distribution system will work together to reduce the energy used by the mechanical system. The UFAD system will reduce the load that the mechanical system needs to condition and the ground source heat pump will meet the lesser loads by means that are much friendlier to the environment and less costly to the owner. The proposed improvements to the lighting of the offices and classrooms will reduce the amount of electricity that the building will need to operate. All of these changes to the initial design will make the construction of the building more complicated and as a result the building will need a new commissioning plan. All of these component work together to increase the energy efficiency of the building.


References

ASHRAE, 2007 HVAC Applications

This book described when the under floor air distribution system is applicable. It also stated several advantages and disadvantages to using an under floor air distribution system. The book also covers ground source heat pumps. It goes into detail about the types of GSHPs available and the benefits and disadvantages of each one.

Hamilton, Sephir D., Kurt W. Roth, and James Brodrick. "Displacement Ventilation." ASHRAE Journal September (2004). Print.

This article describes the advantages of displacement ventilation with UFAD systems. It goes on to discuss the energy saving potentials and the increased occupant comfort that accompanies displacement ventilation

Li, Yuguo, Peter V. Nielsen, and Mats Sandberg. "Displacement Ventilation in Hospital Environments." ASHRAE Journal June (2011). Print.

This article discusses how displacement ventilation works and the possibilities for improving indoor air quality. The article specifically looks at its application in hospitals where excellent IAQ is necessary but the same type of system could be applicable in the Bowie State Fine and Performing Arts Center.

McDonell, Geoff. "Underfloor & Displacement: Why They're Not the Same." ASHRAE Journal July (2003). Print.

This article points out the differences between UFAD systems and displacement ventilation systems. It describes the more technical aspects of both systems and lays out the advantages and disadvantages of each.

McQuay. Geothermal Heat Pump Design Manual. Staunton, Virginia: McQuay International, 2007. Print.

This manual was written by a manufacturer of GSHPs and therefore it is biased toward the advantages of them. However, it describes several different types of GSHP systems and the different requirements for each system.


"Summer Cooling and Heat Destratification with Big Ass Fans." Industrial Ceiling Fans, Commercial Ceiling Fans, Residential Ceiling Fans. Big Ass Fans, 2011. Web. 6 Dec. 2011. <http://www.bigassfans.com/how-they-work/>.

This is a manufacturer’s website that discusses the advantages of large diameter, low velocity fans. It contains several different products that would be applicable to large spaces such as the atrium and includes an in depth description of the advantages to reducing stratification and increase air flow in large volume spaces.


Appendix A: Spring Schedule


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