UW- Energy Audit Class Lowell Hall TeamB 080715

UW- Energy Audit Class

Energy Efficiency Measures (EEM) for Lowell Hall

Sarah Maston, Ryan Meyers, Kevin Preuss & Paul White

Executive SummaryOver the 1st week of August, our team provided a Level 2 Energy Audit of the Lowell Hall Building on the University of Wisconsin’s Madison Campus. We looked for Energy Efficiency Measures (EEMs) for the building envelope, lighting, and HVAC systems. After some quick calculations, we found that:

EUI = 119.2 kBtu/SF/yr (EnergyStar National Median EUI = 74)

ECI = $1.66/SF/yr

…which indicates a myriad of opportunities for improvement. We have included 5 EEMs for consideration. The first EEM for the building envelope, has a lengthy payback, but may want to be considered for other reasons. EEMs 2-4 have simple paybacks of under 4 years. EEM-5 addresses a code violation. We also listed other EEMs for consideration.

Energy End Use Pie Charts (Gas & Electric)

Annual Energy Use

Building EUI:119.2 kBtu/SF/yr

Building ECI:$1.66/SF/yr

Monthly Energy Use

EEM-1: Replace Inefficient Windows

• By reviewing the background information on Lowell Hall, that was provided, we determined that some of the windows were less efficient than others.

• We originally were going to propose replacing the 7700 SF of the old glass windows with high-performance glass, but the payback was too large.

kBTU Savings Cost Savings (Annual)

Cost to Install Windows

SimplePayback

583,552 $3282 $80.75/ SF 191 years

EEM-2: Add Time Clock to Dining Rm Lights

• During our building walkthrough, we noted that the cove lighting in the Dining Room stayed on 24/7, which is very inefficient.

• We propose adding two time clocks to the lighting circuits for the cove lighting in the Dining Room. This time clock will turn the lights off over night, when no one is using the space.

kWh Savings Cost Savings (Annual)

Cost to Install Time Clocks

SimplePayback

2135 kWh $278 $910 39 months

EEM-3: Reduce Redundant Lobby Lighting

• During our building walkthrough, we thought that the lobby lighting was excessive.

• We recommend reducing the cove lighting by ½ and wiring the ballasts in tandem.

kWh Savings Cost Savings (Annual)

Cost to Remove Lights/ Rewire Ballasts

SimplePayback

8970 kWh $493 $904 1.83 years

EEM-4: VFDs for CHW & HW Pumps

• During our walk-through, we noted that the primary CHW pump and the duty/ standby HW pumps had their balancing valves throttled down to 60% open.

• The VFDs for these pumps were operating in hand, at 100%. This is extremely inefficient, and there was no indication as to why this was done.

• We recommend opening the balancing valves to 100% open and then adjusting the pump speed down until the control valves in the system at the furthest point from the pumps just start to close down.

Estimated CHW Pump Power Savings

Savings Cost Savings (Annual)

Cost to AdjustSystem

SimplePayback

3 HP 6,445 kWh $354 $300 10 months

Estimated HW Pump Power Savings

Savings Cost Savings (Annual)

Cost to AdjustSystem

SimplePayback

5 HP 32,674 kWh $1797 $300 2 months

EEM-5: Add modulation to OA damper (HV-1)

• During our walk-through, we noted that the outside air (OA) damper to HV-1, serving the conference room did not modulate to bring in OA when the room was occupied.

• The OA damper had been linked with the return air damper with a 2-position switch, such that the OA damper was either 100% open or 100% closed. The default is 100% closed, which does not provide the code-required fresh air to the room.

• We recommend adding controls, such that the OA damper can modulate to bring in OA to meet the code requirements.

Current Difference with damper open

Savings Cost Savings (Annual)

Cost to Install Controls

SimplePayback

2.3 A 2135 kW $35.11 $300 8.5 years

Additional EEMs to be Considered• The following are other issues that we witnessed in the building. Some

additional research is required to determine costs and paybacks:• Consider replacing the 2 oversized HW boilers with modular condensing boilers. • Consider replacing oversized chiller with smaller chiller to reduce cycling.• Investigate use of check valves on two condenser water pumps that are tied

together, to eliminate risk of recirculating water without cooling.• If replacing boilers is not possible, investigate installation of controls on both

Kewanee boilers to control boiler temperature based on outside temperature.• Investigate potential for shutting down chiller pumps PE-3 on inlet side, or P1 on

outlet side, of new chiller. Pumps are rated for 678 gpm. System requires 555 gpm. Pump P1 is connected to VFD, but 40% closed.

• Building automation system is not utilized effectively, nor is it installed completely. Consider bringing in vendor for training.

• Replace roof section that was not replaced in the last renovation. Many guest rooms are very hot.

Conclusions

There are many opportunities to improve the efficiencies of the systems in this building, but we have only focused on five key EEMs. With more research and time, more opportunities can be explored.

Best Wishes!