Saving some (cookie) dough: finding efficiencies in an ice cream factory
by Tim Perrin, Senior Account Manager
There’s nothing quite like the taste of a cold scoop of ice cream on a hot Vermont summer day. While it’s a staple in most households, many people probably don’t think about the amount of energy that goes into making this delicious treat. Working with a Vermont-based, world-famous ice cream maker has given me some insight into this energy-intensive process.
The industrial peak initiative
Last August we launched a new pilot initiative to help Vermont’s largest manufacturers reduce their energy costs. The Industrial Peak Initiative focuses on reducing expensive spikes, or peaks, in electric usage that can cause a business’ annual electric rate to increase significantly. These peaks also increase the demand on the state’s electric grid, making it more costly to maintain.
The program began with 19 large manufacturers, including Ben & Jerry’s. I worked in the company’s production facility in St. Albans, VT to help them assess and reduce their energy use. Using their 15-minute interval data and submetering equipment, we were able to monitor and analyze the plant’s electric usage. This information helped us to identify the equipment that contributed most to their electric peaks. We found that on hot days, when the refrigeration systems have to work extra hard to freeze and keep ice cream between negative 20 and negative 40°F, these peaks in usage occur more frequently.
Working with a team of contractors and Ben & Jerry’s plant engineers, maintenance staff, and sustainability staff, we focused on two major areas of the operation to reduce their energy demand and improve the performance of the facility. We started by adding variable speed drives to control the horsepower of their refrigeration units. These controls cause the refrigerators’ ammonia compressors and evaporator fans to better match the needed refrigeration load, rather than running full force all the time.
Our second area of focus was on the plant’s lighting. We switched their distribution freezer, production room, mix-making area, and spiral freezer lights to LEDs. This made a particularly big difference in the spiral freezer, which is kept at negative 40°F. Because of the extremely cold conditions, the original fixtures took a long time to warm up and fully illuminate the room; therefore they were left on at all times to keep the area appropriately lit. LED bulbs function much better in cold temperatures and reach full brightness instantly, so the lights can now be shut off when the space is unoccupied, which is about 90% of the time.
Significant savings with statewide benefits
With these upgrades in place the St. Albans plant is saving $89,000 and 1,012,000 kWh annually – enough electricity to power 96 homes for one year. In addition to decreasing their electric costs and peak use charges, they have also reduced their demand on the electric grid. This reduction has been particularly important for the City of St. Albans, which has been a resource constrained region in the past, and an area of focus for Efficiency Vermont’s recent geographic targeting efforts. The Industrial Peak Initiative has also helped Ben & Jerry’s reduce their operating costs and environmental impact, allowing them to further their missions of sustainable financial growth, climate justice, and of course, making fantastic ice cream.
What’s your favorite Ben & Jerry’s flavor? Let us know in the comments below!