Case Study: Energy Upgrades Lower Operating Costs
The energy services division of Horizon Solutions conducted an engineering assessment of the mechanical processes and electrical systems in the Lyrton Inc. manufacturing facility. The audit found opportunities that would lower business operating expenses and improve the bottom line. Project type: Makeup Air Unit (MAU), Variable Frequency Drive (VFD) and motor replacements, and LED lighting upgrade.
Reducing Energy Consumption
Lytron specializes in custom liquid cooling solutions. They design and manufacture cold plates, chassis, chillers, cooling systems, and heat exchangers for some of the most demanding thermal management applications. Headquartered in Woburn, MA, the Lytron manufacturing facility operates two, nine-hour shifts Monday through Friday and a six-hour shift on Saturday. The building uses electricity for lighting, cooling, and various plug loads, and natural gas for space and domestic hot water heating. This facility needed to lower their energy costs.
Horizon Solutions identified multiple opportunities for energy savings, and implemented the following energy upgrades:
- Installed 80/20 MAU (Makeup Air Unit) in place of 100% OA (Outside Air) MAU An 80/20 MAU recirculates up to 80% of the air handled by the MAU. In other words, you have to heat a minimum of 20% cold outside air instead of 100%. The existing 100% OA MAU meant that 100% of the outside air had to be heated. The new 80/20 MAU will result in significant natural gas savings for Lytron.
- Installed 15 HP Premium Efficiency Motor on existing exhaust fans This is an important upgrade for 2 reasons: (1) a few points inefficiency were gained by installing the new motor and (2) the new motor has class F insulation, which can handle higher heat demand when a VFD is used, as compared to the insulation of the existing motor.
- Installed 15 HP VFD to control exhaust fan motor speed The 15 HP VFD allows exhaust fan motor speed to be adjusted in order to correspond to a number of weld stations in use. Fan airflow is proportional to motor speed.
- Installed (11) shutoff butterfly dampers in weld station exhaust ducts Each weld station has its own branch exhaust air duct. Shutoff dampers shut off exhaust fan flow when weld stations become inactive. When a welding arc is struck, the shutoff damper for that station opens, exhausting the weld fumes. When a welder shuts the station down, the damper closes after a 2-3 minute time delay.
- Installed static pressure sensors to provide control variable to above 15 HP VFD Static pressure sensors serve as the indicator for how many weld stations are in operation at a given time and play a role in determining exhaust fan flow.
- Installed controls to ensure adequate fume removal from weld stations Controls use signals from pressure sensors to help select exhaust fan speed, and corresponding exhaust fan flow required for the total number of weld stations in operation at a given time.
- Installed suitable motors, VFDs, and controls on six existing rooftop exhaust fans to ensure satisfactory space air pressure levels are maintained Maintaining satisfactory air pressure levels ensures there is sufficient airflow for personnel working in the space, and that sufficient air is exhausted to dilute air contaminants. With the addition of the weld fumes exhaust system, on average, there is a sufficiently smaller total airflow being exhausted as compared to the existing condition that did not have the weld fumes exhaust fan VFD. Because of this, an assist from the six existing rooftop exhaust fans was needed. Pressure sensors detect high pressure, send a signal to the controls which then activate the motors on the rooftop exhaust fans, producing exhaust flow sufficient enough to maintain a slightly positive pressure in the room.
LED Lighting Component
- Removed 8 ft. linear fluorescent industrial shades and replaced with Lithonia 6000 Lumen LED shades
- Task lighting changed to 4 ft. Lithonia ZL LED shades
- All existing 2x4 ft. and 2x2 ft. T8 Recess Prismatic Troffers changed to Lithonia GTL Acrylic 30L LED troffers
- Existing 2x4 ft. and 2x2ft. 2 lamp T5 office fixtures replaced with Lithonia FSL 30L LED troffers
- Installed exit signs with emergency bug eyes (select locations)
- Exterior fixtures replaced with RAB wall pack and Lithonia
The project was completed in two phases:
- Phase 1 was completed in April 2016 and included the weld fumes exhaust control system and LED lighting upgrade
- Phase 2 was completed in July 2016 and included MAU completion
Jason Stokes, Maintenance Supervisor, Lytron — "Everyone is very happy with the lighting and it makes the facility look better. The machine operators were skeptical at the beginning with the VFDs being put on the welding stations but they are very happy and surprised at how well they work. We also expect to save significantly on our natural gas next winter, something that has us very excited."
The energy upgrades outlined above resulted in significant energy cost savings for Lytron. Horizon Solutions worked with the utility representatives from Eversource and National Grid to confirm a guaranteed incentive, even negotiating a higher incentive amount than originally proposed from both utilities.
Additionally, the project had a substantial, positive impact on the environment. The mechanical and lighting components of Lytron's energy upgrade project helped to decrease air pollution and environmental damage by significant amounts. Combined, the projects removed 583,594 lbs. of carbon dioxide, 817,836 grams of sulfur dioxide, and 3,431,169 grams of nitrogen oxide from the atmosphere. Each of these pollutants causes significant environmental damage. Global warming is caused by carbon dioxide, sulfur dioxide, and nitrogen dioxide cause acid rain, and nitrogen dioxide also produces smog. By removing these pollutants from the air, Lytron's combined mechanical and lighting projects had the same impact on the environment as:
- Planting 66 acres of trees
- Removing 67 cars from the road each year or saving 43,061 gallons of gasoline
A much-appreciated thank you to Tony Parente, Barney Judge, and Michael Pace for their contributions to this article. Don’t miss our other case study blogs:
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