Designs, Upgrades Cut Costs for Ammonia Refrigeration Operators
It’s common knowledge that efficiently built facilities allow operators to increase their profits by reducing energy spending. But ammonia refrigeration companies, contractors and end users may be unaware of some less common knowledge . . . that electric utilities offer incentives to companies that design and build or retrofit facilities to improve energy efficiency. Different programs offer various approaches and incentive structures to achieve savings, and regardless of the utility program, any owners and operators may be able to make the changes it takes to collect those incentives – at little-to-no cost.
AVAILABLE FUNDING
Roughly two-thirds of utilities currently offer efficiency incentive programs, said Marcus Wilcox, chief executive officer of Cascade Energy. And they are doing it because they are required to by legislation, have capacity limitations or want to provide a customer service. “They could be short on production or distribution or the Clean Power Act will restrict their ability to use coal,” Wilcox said, adding that some utilities simply want to focus on efficiency. “It broadens their portfolio,” he said, adding that increasingly, utilities are seeing energy as a service rather than a commodity. Energy efficiency broadens the scope of these services.
The money to fund the incentives typically comes from funds utilities collect as part of their customers’ bills. “Part of the rates their customers pay goes to fund energy efficiency programs. Often 2 to 4 percent of an electric bill goes into this program kitty,” Wilcox said.
The programs vary by region and typically offer technical assistance and training in addition to incentives. “They may also fund energy management information systems —software that allows the customer to track energy use — or custom energy analysis and design consultations,” Wilcox said. Available programs typically include both incentives and loans. “For the vast majority, it is simply called an incentive. When the project is done, the program verifies the savings the project delivers and will pay incentives based on that measured and verified savings,” Wilcox said.
Some utilities offer on-bill financing in which they make the operator an initial loan, which is paid back each month via the utility bill. “The idea being the savings pay for it,” Wilcox said. The types of funding available may vary depending on whether operators are undergoing new construction or addressing existing operations. A lot of industrial refrigeration projects require customized programs. “These are complex systems and complex upgrades. It requires modeling and work to determine the savings,” Wilcox said.
On a retrofit in which operators are replacing or modifying a specific piece of equipment, utilities calculate the cost to be the entire cost of replacement whereas on new construction, they incentivize operators for incremental project costs.
For new construction, utilities may consider the state energy code. Certain states require certain energy efficiency minimums. “The utility program will fund energy efficiency above and beyond what is required,” Wilcox said. An example is Title 24 in California, which has very specific minimum requirements for refrigeration system and refrigerated warehouse equipment, systems and overall design.
State requirements vary widely, and it can be more of a challenge to go above and beyond an aggressive state energy code on new construction, but it is possible, Wilcox said. He suggested operators begin working directly with their utility providers to learn about the specific incentives available in their areas. “Talk to the utility as early as possible, as most efficiency programs may not provide incentives for a project that is already underway or complete,” he said.
THE SAVINGS
As an operator at a dairy processing plant, Todd Toburen worked with Cascade Energy to improve the dairy’s energy efficiency. Less than a year ago, he became a technical advisor at Cascade Energy, but it was his first-hand experience as an operator that showed him how beneficial the programs could be.
While at the dairy, he took part in the Refrigeration Operator Coaching program that provides low-cost and no-cost solutions, used Cascade’s best practices guide and invested in energy management software that gave him 15-minute snapshots of energy usage.
“We saved 1 million kilowatt hours. In Portland, Oregon, that equated to about $85,000 in annual savings,” Toburen said, adding that Energy Trust of Oregon had an incentive program that the dairy was able to use. “It takes time and effort, but there is a payoff.” To put this energy savings into perspective, the savings would power approximately 100 homes, as an average U.S. home uses around 10,000 kilowatt hours per year.
Toburen said energy efficiency programs bring everything together. “People are in the production business to produce a product, but at the same time, they are there to make money,” he said. “The changes we made at the dairy were right in tune with saving the company money and still complying with all of the rules and regulations put forward by OSHA and EPA,” he said.
The energy management software could also help operators identify problems with systems. “When you look at it and one week is high, you ask, ‘Why is that?’ Maybe you’re drawing more amperage on something or you are using a compressor more,” Toburen said, adding that he found it interesting to look at energy use. “You can go online and look day to day and compare apples to apples and see if changes you made have lowered your energy consumption.”
“With most coils, ice forms and it takes energy to melt the ice off. It is important to upgrade the defrost configuration and controls so it is the most efficient defrost as possible. Also look at heat recovery. Every BTU of refrigeration load that a system provides goes to the outdoors. Energy analysis often indicates that it is a benefit to reclaim that heat so it can be used for wash-down water or other applications.”
Marcus Wilcox, chief executive officer of Cascade Energy.
As part of the ROC coaching program, operators take part in training. “I benefited the most from sitting in a classroom and having someone explain everything to me,” Toburen said. “It gives people an idea of what it costs you to leave a door open or build up scale on your condensers. It makes you think.”
The Refrigeration Engineers and Technicians Association also offers training for site personnel to gain the skills and information required to drive energy efficiency improvements on their own systems, Wilcox said. The program is called the Certified Refrigeration Energy Specialist training and certification.
Now that Toburen is out in the field, he said he sometimes gets pushback from operators when he suggests they make changes. Many times operators stick with what they’re doing because they’ve always done it a certain way. “Or they’ll say they tried it and it never worked,” he said, adding that he works to get operators to have an open mind.
Wilcox said energy efficiency programs can get left in the dust because they aren’t first and foremost on people’s minds.
With new construction, the design process is long and complex and involves a lot of parties, which can hinder the adoption of energy efficient technologies. “Someone has to take ownership or participate in the energy efficiency program, and often that is not clear,” Wilcox said.
Vendors may be hesitant to recommend customers look at a program because they don’t want to delay a sale or hold up construction even though they may be aware of an energy saving opportunity or a more efficient piece of equipment, Wilcox explained.
SYSTEM UPGRADES AND CHANGES
Operators have a number of options when looking at energy efficiency improvements, whether for new construction or upgrades. Wilcox said addressing energy efficiency during construction is cheaper. “If you don’t do it then you’ll have to do retrofits later and it will cost a lot more.”
When looking at a new system, engineers should work to reduce the load from the beginning. “It could be with insulation, types of doors, or different forms of cooling and heat recovery,” Wilcox said. The next step is to minimize system lift — the difference between the cold side and the hot side of a system. “It costs more to lift the heat if they are very far apart,” Wilcox said, recommending that anyone looking to minimize lift should look at coil selection, partload performance and system design to keep lift to a minimum. “Designers want the system to be able to trim or scale back in an efficient fashion,” Wilcox said.
For operations, variable speed control in the fans and compressors can reduce energy use as well.
The next category the company works on is efficient defrost design. “With most coils, ice forms and it takes energy to melt the ice off. It is important to upgrade the defrost configuration and controls so it is the most efficient defrost as possible,” Wilcox said. “Also look at heat recovery. Every BTU of refrigeration load that a system provides goes to the outdoors. Energy analysis often indicates that it is a benefit to reclaim that heat so it can be used for wash-down water or other applications.”
Another way to reduce the energy use of the refrigeration system is to reduce condensing pressure. “There are misconceptions on what a system can run at and this should be considered,” Toburen said. “If you can lower the head pressure, your compressor isn’t going to work as hard.”
Wilcox said operators can consider a central computer control system that manages everything with a focus on energy efficiency. There are also tune-up programs that utilize targeted cleaning, repairing and tuning of existing equipment.
Toburen admitted that from an operator perspective, energy efficiency was one of the last things he looked at. He changed his perspective once he learned more about the benefits energy efficiency provides. “I learned if I am doing it efficiently, I am doing it safely and I am doing the things EPA and OSHA want you to do to keep a facility running,” he said. “It is one of those things you sit back and say, ‘Why wouldn’t you want to do it?’”