Environmental concerns as well as the rising cost of energy have spurred the pharmaceutical industry to become more energy-efficient. Manufacturers are taking a hard look at ways to increase efficiency of their core equipment: motors, drives, pumps and valves.
Fortunately for manufacturers, many associations, government agencies and standards organizations have launched programs to facilitate energy efficiency improvements. Guidelines, tips and standards are in place to help companies increase efficiency, conserve natural resources and reduce emissions.
The National Electrical Manufacturers Association (NEMA) unveiled its Premium efficient electric motor program in 2001. These motors exceed the minimum energy efficiency standards required by the Energy Policy Act of 1992. In addition, NEMA Premium sets efficiency standards for an increased range of motors. NEMA Premium efficiency may be applied to general-, definite- and specialpurpose products from 1-500 hp operating on low or medium voltages. This spring, NEMA approved a standard for 50 Hz motors for premium efficiency to complement the existing 60 Hz standards.
The Consortium for Energy Efficiency (CEE), a non-profit group that includes many electric utilities among its members, recognizes NEMA Premium motors up to 200 hp as meeting their criteria for possible energy efficiency rebates. Although many motors exceed NEMA Premium efficiency ratings, motor manufacturers that are not NEMA members cannot use the NEMA Premium trademark. So, be sure to check the nameplate efficiencies to compare.
The Copper Development Association offers MotorMaster+ software, which was developed for the U.S. Dept. of Energy (DOE) by engineers at Washington State University to compare the true cost of owning motors of several efficiencies.
Improving motor efficiency is critical for pharma companies, as motors typically consume 70% of a plant’s electricity, according to Southern California Edison (SCE). SCE suggests the following measures to boost motor efficiency:
- Replace standard-efficiency motors that are greater than 1.5 hp and run more than 6,000 hours per year with energy-efficient motors.
- Adjust the sheave and speed of the impeller components of the device attached to the motor (e.g., stirrer and pump) to match the desired outflow.
- Install variable speed drives (VSDs) on pumps instead of valves.
- Install VSDs on fans previously controlled by dampers; this controls airflow more efficiently.
- Add sensors to control ventilation levels in various plant areas (such as a cleanroom).
For example, Genentech (Vacaville, Calif.) replaced the inlet vanes for the supply and return fans with VSDs on six variable volume handlers in the building. The VSDs reduce the horsepower of the fans to reduce flow; thus reducing fan motor energy use. The annual energy cost savings is about $23,000 with a reduction in peak load of approximately 40 kW.
Pumps also can consume substantial energy. The DOE’s Pump System Assessment Tool (PSAT) can help a company analyze its pumping efficiency and estimate energy and cost savings. (For more information on PSAT, visit the Best Practices Website at www1.eere. energy.gov/industry/bestpractices.) The DOE has teamed up with the Hydraulic Institute (HI; www.pumps. org) to produce “Improving Pumping System Performance: A Sourcebook for Industry.”
HI is a non-profit industry association that provides product standards and a variety of energy-related resources for pump users and specifiers, including training and guidebooks (visit www. pumplearning.org and www. pumpsystemsmatter.org).
Measures advocated by the DOE to improve pumping system efficiency include:
- Shut down unnecessary pumps. Use pressure switches to control the number of pumps in service when flow rate requirements vary.
- Restore internal clearances.
- Replace or modify oversized pumps.
- Meet variable flow rate requirements with an adjustable speed drive or multiple pump arrangement instead of throttling or bypassing excess flow.
An added motivation for companies to reduce energy usage is that many energy organizations offer incentive programs for motors and drives. Such programs support a range of measures, from simple equipment upgrades to large-scale retrofitting or new construction projects. They also may provide support for education and training.
Publicly funded energy-efficiency programs vary greatly and are administered by several different types of organizations. Generally, budget and administrative oversight are authorized by the state legislature, while regulators within each state are tasked with approving program designs and determining to what extent the organizations administering programs are reimbursed for their efforts. In 2006, approximately $2.6 billion was budgeted for these programs in the U.S. The CEE provides a summary of these programs at www.motorsmatter.org.
Below, we showcase energy-efficient motors, drives, valves and pumps that have been introduced recently.
DME series digital dosing pumps have an easy-to-use HMI that gives operators ready access to standard control features, including pulse, analog, timer, batch and anti-cavitation control. The pumps can be adjusted to 1/800 of their maximum capacity. Two new sizes provide more flexibility, from 0.02 to 39.6 GPH (75 to 150 ml/h). A brushless DC motor eliminates the need for a servo motor or a frequency converter. For handling viscous polymers or other difficult liquids, you can slow down the speed of the suction stroke to 75%, 50%, or 25% of the maximum.
Grundfos Dosing, Marietta, Ga. www.grundfos.com/dosing
Brushless Motor and Control
The adjustable speed Brushless Motor Control (BMC series) is easy to use and set up without programming — user trimpots and jumpers are factory-set and will work for most applications. Input command signal may be +/- 10 Vdc, a 5K speed pot, or a form “C” contact or relay for forward-stop-reverse operation. Coupled with the BMC control, the brushless motor (BSM series), provides better than 0.5% speed regulation. These packages operate directly from 115 or 230 Vac input voltage, providing accurate speed controllability for applications to 3 HP (0.18-2.2 Kw).