Well-designed optimization projects can minimize resource use in chilled water plants like this one at a Southern California pharmaceutical facility, resulting in immediate savings and significant contributions to sustainability goals. (Photo above by Optimum Energy)
Heating, ventilation, and air conditioning (HVAC) systems—the chilled water plant, steam and hot water plant, and air distribution—consume 65 percent of the energy used in pharmaceutical manufacturing facilities, according to research by Lawrence Berkeley National Laboratory. Chilled water plants also consume substantial amounts of water.
That makes these systems ripe for optimization. Minimizing their energy and water use can make a major contribution to reaching sustainability goals and reducing operational costs.
Well-designed HVAC optimization projects provide payback in three to five years, with savings starting immediately.
In addition, HVAC optimization provides energy monitoring and fault detection, which can enable facility personnel to improve operations without increasing headcount.
Optimization means monitoring and automatically and continuously controlling HVAC equipment as a holistic system to maintain desired facility conditions using the least amount of energy. This goes beyond recommissioning or modifying traditional static setpoints and PID-based controls.
To deliver consistent, reliable savings, HVAC optimization requires three elements: measurement, a system-level approach, and automatic control.
These charts, from Optimum Energy OptiCx dashboard for a pharmaceutical facility installation, compare year-over-year efficiency (top), and dollars and energy savings (below).
Measurement: Measuring both the energy input and the system output is essential for data-based optimization because varying the energy input of any piece of equipment will vary the total system output.
System-level approach: A system-level approach is key to effective HVAC optimization because it prevents unintended side effects that can occur if you optimize components one by one. Reducing the output of one component may cause other components to increase their energy use.
Automatic control: A truly optimized system requires continuous, automatic control. Solutions that call for human intervention to implement optimization recommendations may provide some energy savings, but real-time, dynamic control is the only way to provide maximum savings without compromising operations.
Making Optimization Work in Pharma
In general, the larger, more highly utilized, and more centralized the facility, the better suited it is for HVAC optimization. Centralized chiller plants and large air handlers present a concentrated target, which usually produces greater savings. These systems cost more to operate, generally have more sophisticated controls, and are more likely to have dedicated staff to operate and maintain them.
Owners of multiple facilities looking to optimize should prioritize buildings based on size, electricity rate, and total utility cost. In particular, facilities with the following characteristics should be priorities for optimization:
- High energy use—the more energy consumed, the greater the benefit.
- 24/7 operations—labs, manufacturing spaces, and nonvalidated spaces that operate year-round are great candidates. Validated (or GMP) spaces can also be optimized, but the expense of extra testing and approvals may make the project slow to pay back.
- New HVAC systems that have not been optimized—controls do not equal optimization.
- Middle-aged HVAC systems (10 to 15 years old)—these often are prime targets. They offer good room for improvement and are worth upgrading.
With Optimum Energy’s OptiCx platform, users can track savings in dollars, energy, and CO2 (top). This dashboard, for a two-chiller plant running OptimumLOOP on OptiCx, shows how much energy the plant is using (bottom), and the bar shows how much of the plant is optimized at a given point in time.
Operational Requirements and Restrictions
It is critical to identify the facility’s particular temperature, humidity, and airflow requirements and make sure the optimization product can operate within those restrictions. This initial feasibility study should include validated spaces that would require additional testing and approvals.
An optimization provider should identify system requirements and develop a plan for addressing all needs with the lowest possible energy input.
Compelling Cases for Optimization
Energy costs, corporate sustainability commitments, and the challenges of operating hodge-podge systems assembled over time are among the most compelling reasons to optimize HVAC systems.
Energy costs: Rising energy costs—due to either rising electricity rates or increased usage—are the sign of a facility that is ripe for optimization. The more you pay for power, the more you will benefit from optimization.
Sustainability mandates: Many corporations have a mandate to save energy and meet sustainability or carbon footprint goals. Johnson & Johnson, for example, has committed to reducing absolute carbon emissions by 20 percent by 2020 and 80 percent by 2050. Part of that reduction is coming from renewable energy purchases, but the cheapest renewable kWh is the one you don’t use.
Mixed equipment: HVAC systems that have been built up over time often have a mix of equipment—: some old, some new, different brands. With mismatched equipment, it is not always clear which is the best combination to run or what is the best set point for a subsystem. HVAC optimization provides the information needed to control complex HVAC systems for the highest possible efficiency.
Determining ROI for Optimization
Start with a quick calculation of savings and ROI: iIf an HVAC optimization package reduces building energy use by five percent and the payback threshold for energy projects is three years, then the project budget for optimization is 15 percent of the building’s annual energy expenditure.
The condition and age of the HVAC system will affect both the cost and the savings potential of an optimization project. The older and less controlled the HVAC system, the larger the potential savings, but also the larger the potential cost to bring the system to optimization readiness. The newer and more modern the HVAC system, the lower the cost and the potential savings.
The size and nature of an HVAC system also affect costs. Larger and more centralized systems concentrate energy use in one place, where it’s easier to measure and optimize. A distributed system, such as one with numerous split-systems or rooftop DX units, will require optimization and monitoring of each independent system and thus will cost more to optimize.
An HVAC system at the end of life provides another opportunity for optimization. If a system is ready for retirement, optimization along with equipment replacement provides a quantifiable financial payback that would not otherwise exist for the capital project. Replacing and optimizing a new chiller may have a 10- to 15-year payback, but replacing the chiller with no optimization may have a longer payback or none at all. This difference in payback could provide the impetus needed to secure funds to replace old equipment.
The Successful Project
A significant number of energy conservation projects do not provide the projected energy or cost savings. To reduce that risk, optimization projects should include the following elements.:
Defined goals: Is the goal to reduce energy costs as an absolute value, or energy cost per square foot, or energy input per unit output? When reducing energy costs, what is the baseline against which energy use will be compared? Answering these questions will ensure that the project has the right targets.
Measurement and verification (M&V): The optimization product should include an M&V method that can report on the effectiveness of optimization versus the organization’s goals. If the organization has a carbon footprint reduction goal, for example, the product should report mass of CO2 reduced in an easy-to-retrieve format.
Road map: A robust road map will provide projected energy savings, an M&V plan, and a detailed plan of the project retrofits and tasks required for optimization. The savings projections and retrofit plan should be developed in partnership with the contractors who will do the work.
Many project managers instead go the traditional route of plan and spec, requesting multiple bids. But optimization is not yet a commoditized product that can be successfully purchased this way; typically, the bid winner is the one who provides the least optimization at the lowest price, which results in missed savings.
Training: As with HVAC controls, HVAC optimization can easily be overridden or bypassed by operators and thus fail to meet savings goals. Proper training will give operators an understanding of how the system is meant to work, what to expect the system to do, and what to do in the event of a problem.
For pharmaceutical manufacturing facilities, HVAC optimization can deliver significant energy savings—which means reduced operational costs—and contribute to achieving sustainability mandates.
An effective optimization project protects current operational requirements and provides full-system testing and robust M&V, resulting in excellent system performance and energy savings year after year.
About the Author
Fred Woo, PE, is manager, engineering, at Optimum Energy.
This story also can be found in the April/May 2018 issue of Pharmaceutical Processing.
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