As pharmaceutical manufacturers face an increasingly competitive environment, they seek out opportunities to reduce production costs without negatively affecting the yield or the quality of their finished products. The volatility of energy prices in today’s marketplace can also negatively affect predictable earnings. This is a concern particularly for publicly-traded companies in the pharmaceutical industry. The challenge of maintaining high product quality while simultaneously reducing production costs can often be met through investments in energy efficient technologies and energy efficiency practices. Energy efficient technologies can often offer additional benefits, such as quality improvement, increased production, and increased process efficiency, which can lead to further productivity gains. Energy efficiency is also an important component of a company’s environmental strategy, as energy efficiency improvements can often lead to reductions in pollutant emissions. A strong energy management program can also provide a solid foundation for corporate greenhouse gas management programs. In short, investment in energy efficiency is a sound business strategy in today’s pharmaceutical manufacturing environment.
A variety of opportunities exist within pharmaceutical industries especially manufacturing facilities and other buildings to reduce energy consumption while maintaining or enhancing productivity. That categorizes available energy efficiency opportunities by the six major activity areas (1) R&D, (2) bulk manufacturing, (3) formulation, packaging and filling, (4) warehouses, (5) offices, and (6) miscellaneous.
For individual pharmaceutical facilities, the actual payback period and savings associated with a given measure will vary depending on facility activities, configuration, size, location and operating characteristics. Hence, the values presented in the Energy Guide are offered as guidelines.
Although technological changes in equipment conserve energy, changes in staff behaviour and attitude can also have a great impact. Energy efficiency training programs can help a company’s staff incorporate energy efficiency practices into their day-to-day work routines. Personnel at all levels should be aware of energy use and company objectives for energy efficiency improvement.
Energy Management Systems
Improving energy efficiency should be approached from several directions. A strong, corporate-wide energy management program is essential. Ideally, such a program would include facility, operations, environmental, health, and safety, and management personnel.
Energy efficiency improvements to cross-cutting technologies, such the use of energy efficient motors and the optimization of compressed air systems, present well-documented opportunities for energy savings. Optimizing system design and operations, such as minimizing laboratory ventilation, can also lead to significant reductions in energy use. In addition, production process can often be fine-tuned to produce similar savings.
A successful program in energy management begins with it a strong organizational commitment to continuous improvement of energy efficiency. This involves assigning oversight and management duties to an energy director, establishing an energy policy, and creating a cross-functional energy team. Steps and procedures are then put in place to assess performance through regular reviews of energy data, technical assessments, and benchmarking. From this assessment, an organization is able to develop a baseline of energy use and set goals for improvement. Performance goals help to shape the development and implementation of an action plan as shown in Fig.1.
Energy Monitoring Systems
Energy monitoring systems and process control systems are key tools that play an important role in energy management and in reducing energy use. Such systems may include sub-metering, monitoring, and control systems. They can reduce the time required to perform complex tasks, often improve product and data quality as well as consistency, and optimize process operations. Monitoring and metering systems also play a key role in alerting energy teams to problem areas and in assigning accountability for energy use. Additionally, such systems can be useful in corporate greenhouse gas accounting initiatives; they are also helpful in profiling energy use. Typically, energy and cost savings are around 5% or more for many industrial applications of monitoring and control systems. These savings apply to plants without updated process control systems; many pharmaceutical plants may already have modern process control systems in place to improve energy efficiency.
The greatest opportunities for energy efficiency exist at the design stage for HVAC systems in new pharmaceutical industrial facilities. By sizing equipment properly and designing energy efficiency into a new facility, a pharmaceutical manufacturer can minimize the energy consumption and operational costs of its plant HVAC systems from the outset. This practice often saves money in the long run, as it is generally cheaper to install energy efficient HVAC equipment at building construction than it is to upgrade an existing building with an energy efficient HVAC system later on, especially if those upgrades lead to production downtime. Later HVAC modification may also require review and approval that can lead to further delays and production downtime.
Setting back building temperatures (i.e., turning building temperatures down in winter or up in summer) during periods of non-use, such as weekends or non-production times, can lead to significant savings in HVAC energy consumption. Similarly, reducing ventilation in clean rooms and laboratories during periods of non-use can also lead to energy savings. In recent studies of laboratories and clean rooms in the pharmaceutical and similar industries, HVAC systems were found to account for up to two-thirds of facility energy consumption. Thus, scaling back HVAC energy consumption during periods of non-use can have a major impact.
Duct leakage can waste significant amounts of energy in HVAC systems. Measures for reducing duct leakage include installing duct insulation and performing regular duct inspection and maintenance – including ongoing leak detection and repair. There is a technique called the Mobile Aerosol-Sealant Injection System (MASIS) to reduce duct leakage. The application of MASIS resulted in a reduction in overall duct leakage from 582 cfm to 74 cfm, leading to a 34% increase in the overall efficiency of the building’s HVAC system.
In facilities with make-up air handling systems, energy can be wasted when cooled make-up air must be reheated. By setting higher discharge air temperatures when demand for cooling decreases, unnecessary reheating of the make-up air supply can be reduced.
Variable-Air-Volume (VAV) systems: Variable-air-volume systems adjust the rate of air flow into a room or space based on the current air flow requirements of that room or space, and therefore work to optimize the air flow within HVAC ductwork. By optimizing air flow, the loads on building air handling units can be reduced, thereby leading to reduced electricity consumption.
Adjustable Speed Drives (ASDs): Adjustable speed drives can be installed on variable-volume air handlers, as well as recirculation fans, to match the flow and pressure requirements of air handling systems precisely. Energy consumed by fans can be lowered considerably since they are not constantly running at full speed. Adjustable speed drives can also be used on chiller pumps and water systems pumps to minimize power consumption based on system demand.
A VAV system with Adjustable Speed Drives (ASDs): The ASDs control the speed of HVAC supply and exhaust fans 25% more efficiently than the standard inlet vane controls that were used in the past. Although the VAV system was a more complicated and expensive control system than the previous system, the VAV system used 30-50% less energy than the previous system did – and thus led to significant energy cost savings over time. The VAV also reduced the volume of air delivered when the building is unoccupied, from a maximum volume of 400,000 cfm, or 15 Air Changes per Hour (ACH), to 160,000 cfm, or 6 ACH, delivering further energy savings.
Heat recovery systems: Heat recovery systems reduce the energy required to heat or cool intake air by harnessing the thermal energy of the facility’s exhaust air. Common heat recovery systems include heat recovery wheels, heat pipes, and run-around loops. For areas requiring 100% make-up air, studies have shown that heat recovery systems can reduce a facility’s heating/cooling cost by about 3% for each degree (Fahrenheit) that the intake air is raised / lowered. The payback period is typically three years or less.
HVAC chiller efficiency improvement: The efficiency of chillers can be improved by lowering the temperature of the condenser water, thereby increasing the chilled water temperature differential. This can reduce pumping energy requirements. Another possible efficiency measure is the installation of separate high-temperature chillers for process cooling.
Building reflection: Use of a reflective coating on the roof of buildings in sunny, hot climates can save on air conditioning costs inside. The use of reflective roofs on buildings can reduce air conditioning demand by 8% – 12%.
Building insulation: Adding insulation to a facility will nearly always result in the reduction of utility bills. Much of the existing buildings in the pharmaceutical industries are not insulated to the best level. Older buildings are likely to use more energy than newer ones, leading to very high heating and air conditioning bills. Even for a new building, adding insulation may save enough through reduced utility bills to pay for itself within a few years.
Cooling towers: In many instances, water cooling requirements can be met by cooling towers in lieu of water chillers. Water towers can cool water much more efficiently than chillers and can therefore reduce the overall energy consumption of clean room HVAC systems. Operating multiple cooling towers at reduced fan speed rather than operating fewer towers at full speed is a further option for lowering cooling water energy consumption.
Reduction of clean room exhaust: The energy required to heat and cool clean room make-up air accounts for a significant fraction of clean room HVAC energy consumption. Measures to reduce clean room exhaust airflow volume can therefore lead to significant energy savings.
Improved load management: Because of the large amount of energy consumed by compressors, whether in full operation or not, partial load operation should be avoided. For example, unloaded rotary screw compressors still consume 15% to 35% of full-load power while delivering no useful work.
Lighting controls: Lights can be shut off during non-working hours by automatic controls, such as occupancy sensors that turn off lights when a space becomes unoccupied. Occupancy sensors can save up to 10-20% of facility lighting energy use. An example of energy efficient lighting control is illustrated by Figure 2, which depicts five rows of overhead lights in a workspace. During the brightest part of the day, ample daylight is provided by the window and thus only row C would need to be turned on. At times when daylight levels drop, all B rows would be turned on and row C would be turned off. Only at night or on very dark days would it be necessary to have both rows A and B turned on.
Cogeneration: For industries like pharmaceutical manufacturing that have requirements for process heat, steam, and electricity, the use of Combined Heat and Power (CHP) systems may be able to save energy and reduce pollution. Cogeneration plants are significantly more efficient than standard power plants because they take advantage of waste heat. In addition, transmission losses are minimized when CHP systems are located at or near the plant. Furthermore, new CHP systems offer the option of tri-generation, which provides cooling in addition to electricity and heat. Cooling can be provided using either absorption or adsorption technologies, which both operate using recovered heat from the cogeneration process.
Figure 3 illustrates the projected energy consumption trend for production of pharmaceuticals over the period 2012 to 2050, based on a BAU scenario.
We found that although most pharmaceutical companies in the market have separate energy management teams or programs, there are still specific opportunities available at individual plants to reduce energy consumption cost effectively in the pharmaceutical industry, both in utilities and in the various processes. In this article, we have identified different energy efficient practices and technologies. Specific energy savings can be obtained for each efficiency measure based on case studies that describe implementation of the measures as well as provide technical references.
Dr. (Prof.) D. B. Jani; an Associate Professor at GEC, Dahod under Gujarat Technological University (GTU), Ahmedabad; received his Ph.D. in Thermal Science (Mechanical Engineering) from Indian Institute of Technology (IIT) Roorkee. Currently, he is a recognized Ph.D. Supervisor at GTU. He published more than 150 Research Articles in reputed International Conferences and Journals along with five popular books. His areas of
research include Desiccant cooling, ANN, TRNSYS and Exergy.