Michaels Energy, with funding assistance from Focus on Energy, teamed with Nestle Nutrition to incorporate energy efficient design features into Nestle’s production facility addition in Eau Claire, WI. The plant will produce infant formula from a liquid feedstock.
Michaels met with Nestle stakeholders to gain an understanding of the production process from receiving through packaging. Energy efficient upgrades were identified in this kickoff meeting. Additional measures were developed as the process was further studied by Michaels Energy staff in La Crosse. A second meeting with Nestle was held to discuss the potential design alternatives and select projects for investment-grade energy analysis.
Measures identified and analyzed include:
- Heat recovery from a continuous drying process to preheat process water with recovered heat further used to heat makeup air for the facility.
- Heat recovery from a batch process using a combination of large silos of water serving as the heat sink and heat exchangers for preheating and precooling product.
- Non-Condensing boiler stack heat recovery for the new boiler and a downstream condensing economizer to recover heat from both the new process boiler and existing process boiler.
- Outdoor air supply for air compressors and purgeless air dryers.
- Variable frequency drive for new boiler burner fan.
- Variable speed ammonia compressors used for making process chilled water.
- Floating ammonia compressor head pressure control.
- Thermosyphon free oil cooling for ammonia compressors.
- Process cooling tower heat recovery used for plant space heating and receiving area snow melt.
- Variable speed cooling tower fans and energy efficient motors.
The above measures combine for $1.2 million in annual energy savings, resulting in a combined simple payback of 1.4 years using trailing energy costs. This includes savings of 1.3 million therms, 1.4 million kWh, and 1.7 MW.
Larry Willi, Senior Facilities and Utilities Engineer for Nestle, plans to use Michaels and Focus on Energy programs for pending projects in the future.