Le Mission Impossible
The Habitat For Humanity Restore Energy Crisis in Christiansburg, Virginia
“How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?” Sherlock Holmes, The Sign of Four
“Watch Me.” Detective James McNulty, The Wire
We - the CHP Auditeers - were asked in desperation to come. There was a local energy crisis. Hope was fading fast. It was looking like the Habitat for Humanity Restore, in its new location, would have to find another new home due to extremely high utility bills.
Only days before, a local newspaper had written a hopeful article about the ReStore moving to its new “great location” that was formerly a large grocery store with a 16,000 sq.ft. sales floor area. “If the store is as successful as we hope, it will help us finance the building of two to four houses a year,” said the nonprofit’s executive director.
However, 2,500 paper green George Washingtons were sent out the door that month for electricity. This was above and beyond the non-profit's budget for utilities, and therefore, that utility bill was spelling "eviction notice" right before their eyes. Or so they thought.
Over a casual discussion with a friend, an employee at CHP Energy Solutions was made aware of the problem. The Habitat for Humanity staff was hopeful that maybe, just maybe, a few of our trained energy auditors could come by and give some general consulting. CHP Energy Solutions volunteered its services for free.
This is where The CHP Auditeers came into the picture.
We were approved to spend 10 hours of our paid time, and we had a limited $300 spending threshold to actually perform any necessary work. The silver lining was that Habitat for Humanity had free volunteer labor available, so the $300 could be spent solely on critical materials.
Here’s how we allocated our 10 hours:
- Guided tour of facility with manager
- Lighting takeoff and output using Light Meter
- Infrared Thermography of building
- Building scan for infiltration
- HVAC visual inspection & thermostat use interview
- Water heater visual inspection
- Analysis and report
We found a lot of issues that could be improved, but only some of the recommendations were performed. Here is what was recommended.
The ReStore had approximately 300 light fixtures that contained two T-8 32-watt four-foot fluorescent lights. The existing average lighting output was approximately 75 foot-candles which provided more than the recommended output of 50 foot-candles for a retail space.
It was recommended to take out one of the two lights from the fixtures. To maintain uniformity, it was recommended to take out the same light location along the whole strip of lighting fixtures. It was also recommended to start with taking out the lighting at the front of the store and work toward the back (due to the natural lighting from the storefront windows.) By removing half of the lights, the lighting energy use would be reduced by approximately 40%, while providing a large quantity of light replacements for future use.
HEATING & COOLING IMPROVEMENTS
The HVAC (Heating, Ventilation, Air Conditioning) systems included three zones with three different heat pump systems in the former bog-box grocery store: the retail area, the storage area, and the pharmacy area.
We prioritized the measures that needed to be improved starting with recommending:
- Install thermostat with capability to limit the auxiliary heating. (It is best practice to keep the auxiliary heat strips off during the off-peak hours.)
- Lower the thermostat setting when store was closed to 50°F and to 65°F when store was open. If the building envelope was sealed and insulated, this lowered the risk of pipes freezing, which made lowering the temperature a viable option. (For every 1°F that the thermostat is reduced the Department of Energy has found it saves 3% in energy costs for a 24-hour period.)
The main goal was to reduce the temperature as low as possible while maintaining comfort for the occupants during the store hours (Wednesday, Thursday, Friday, Saturday 10 AM—6 PM). Use of the auxiliary heat strips would be reduced if the thermostat setting was on a dynamic schedule that slowly ramps up and down the temperatures using the heat pump alone. (10 SEER Heat Pump—2-2.5 COP / the auxiliary heat strips—1 COP)
3. Shut off air handler in the back fo the store if not critical to maintain comfortable temperatures in storage area in back.
4. Clean filter by vacuuming dust and debris. Replacing it would be best practice but it was a much costlier option. (Last recorded replacement was 12/29/10.) If at the very least it was taken out and cleaned, this would improve air flow, efficiency, and more importantly, indoor air quality.
The ductwork was insulated in all visible locations. The ductwork was not sealed and was extremely leaky. There were loud banging sounds emanating from the main air handler. This was caused by a duct connection that was not fastened correctly.
To improve the performance of the ductwork the following measures need to be performed:
1. Fasten loose duct part that is noisy/ leaky.
2. Air seal all connections and joints in duct work with mastic/ mastic tape.
WATER HEATER IMPROVEMENTS
There was a 20+ year old, 120-gallon electric water heater located in the rear of the building. There seemed to be no demand for hot water in the building.
1. Turn off water heater. If hot water is ever in demand, then wrapping the water heater and pipes was recommended. Wrapping the pipes would also be a wise investment to prevent the pipes from freezing if the temperature in the rear semi-unconditioned area gets below freezing.
AIR LEAKAGE IMPROVEMENTS
There were significant breaks in the thermal and air barriers in the building’s shell. In the rear of the building there were direct openings in the wall, and in the front of the building the automatic sliding glass doors allowed direct unconditioned air to infiltrate the retail air, greatly hampering controlled comfort.
Unconditioned/ uncontrolled air was coming into building's rear wall location through the old chillers’ line openings which were not in use anymore. Also, the metal louvered area in the rear wall was allowing air and moisture to infiltrate the building.
The infrared images revealed differences in temperature due to the lack of insulation and/or ceiling panels. Missing ceiling panels decreased the effectiveness of controlling the air and thermal settings of the building. Reinstalling insulation and ceiling panels would give a more complete air and thermal barrier in this area. Use of a lift was donated by CHP Energy Solutions Training Center to perform this measure.
So what happened in the end?
A month after implementation based on our recommendations, we received an email from a Habitat for Humanity board member stating that the Restore's energy bill “was down $1,000,” attributed to the improvements.
This hopeful fairy tale ending meant they could stay in their new store location. They could now pay the bills, conserve energy, and hold onto the hope that soon they could save enough money to build new homes for those in need.
Community Housing Partners
CHP develops, designs, manages and sells affordable housing and delivers energy conservation training and contracting across the southeastern US. CHP is a 501(c)(3) community development corporation that serves the needs of low-wealth and low-income individuals and families.
CHP Energy Solutions
CHP Energy Solutions provides expert training and building performance upgrades to create healthier, safer, more durable and energy-efficient environments using proven methods in energy efficiency, health and safety, and indoor air quality (IAQ). Our credentialed and experienced professionals have a proven track record of success helping property owners, contractors and building operators improve residential and commercial buildings.
Benjamin Knopp and Jon Bluey are the Simon and Garfunkle of the energy auditing world. Benjamin Knopp has spent time abroad (Germany) and at home learning about the newest technologies in the energy conservation world. He also holds a few Building Performance Institute certifications. Benjamin, according to Jon, has a natural way for all things building science. Jon Bluey has held various professions which include high school literature teacher, landscaper, construction manager, and adult educator. His varied passions have allowed him to pursue a construction management degree from Virginia Tech, a green roof installer certification. He also holds many three- and four-lettered building science certifications which include: BPI, HERS, and CEM.
Habitat for Humanity Restore of the New River Valley
The ReStore is a thrift store concept for building materials, gently used furniture, lighting & plumbing fixtures, tools, appliances, and lots, lots more! The store accepts quality donations from the public, individuals and businesses, uses mostly volunteer labor, and the profits go directly toward our charitable mission to provide affordable housing. We love donations!
1675 North Franklin, Christiansburg, VA 24073
Open Tues-Sat 10am - 6pm