Beyond Efficiency: Five Attributes to Consider for Energy Savings and Reliability
by Shams Shaikh, Director of Product and Strategy, Infinitum Electric
As we think about the next generation of manufacturing, the 2021 NEMA “Beyond Efficiency” initiative challenges Members to develop innovative products for increased energy savings and reliability. And from Infinitum Electric’s experience developing next-generation motors, we believe this goal hits precisely where the future of electrical manufacturing is heading.
Over the years, efficiency has become standard for many products, but efficiency alone misses the real opportunity. Energy-efficiency levels in most electrical products and components are reaching their technological and economically justifiable limits, but systems composed of these components can still be optimized further to provide increased energy savings, productivity, and reliability. When designing and developing products, the real goal should consider the total energy consumed at the system level vs. component-level efficiency.
As businesses prepare for more workers returning to office buildings, let’s consider heating, ventilation, and air conditioning (HVAC) fan-motor drive systems as an example. You have several ways to optimize the design of the fan-motor drive system for system-level efficiency:
• Option A is to optimize the fan design for airflow requirements, with more degrees of freedom in design when you deploy a variable speed motor to allow different sizes of fan wheels.
• Option B is to improve the motor efficiency to provide optimum power for the same amount of airflow.
• Option C is to choose a motor system that enables ease of installation and maintenance to lower overall lifetime costs.
Many of the attributes in next-generation motors that contribute to energy efficiency also make them more reliable and easier to manage, which reduces lifetime operating costs and enables a faster return on investment (ROI). Next-generation motors are delivering on just that for many HVAC systems in the field, and their attributes consist of:
1. Compact Form Factor
The choice of a small and lightweight motor affects the overall efficiency of a fan array system and, therefore, the electricity consumed. The ability to use lighter, smaller equipment leads to reduced installation costs, as larger systems require heavy equipment to install and have higher associated manufacturing costs.
2. Integrated Motor and Drive
With an integrated drive, the motor speed is fully optimizable, and there is no need to purchase or mount the drive externally, which reduces the amount of wiring in the system. It also shortens the commissioning time for setting up a fan or pump application.
Higher horsepower (HP) motors make fan systems more efficient. The optimal case is a small form factor motor at a larger HP rating.
4. Reliability by Design
Windings are typically the main point of failure for motors, but new copper-etched printed circuit boards (PCBs) increase reliability and allow for embedded sensors. PCB stators also eliminate one of the most common causes of motor failure: unbalanced voltages and currents induced in the stator and rotor cores due to high-frequency harmonics, which can degrade the bearing lubricants and eventually lead to bearing failure.
Internet of Things (IoT) connectivity and predictive maintenance can ensure the system is continually operating efficiently to maximize energy savings and minimize expensive and inconvenient downtime.
As mentioned above, there are many ways to optimize the design of the fan-motor drive system for system-level efficiency. Choosing a motor system built for reliability and ease of maintenance is an excellent way to optimize operating costs and energy savings. Using next-generation motors has also contributed to much faster ROI through better HVAC system performance, greater intelligence for improved reliability, lower maintenance and operating costs, and energy savings over the system’s life.
Going beyond efficiency requires thinking about the whole, rather than the sum of the parts and their total impact on users and the environment over the system’s life. If all of us innovate with this in mind, we will create products needed for the next generation.