Many water and wastewater treatment plants still employ inefficient electric motors. Modernizing motor systems is critical for cost reduction, meeting expanding demand, and lowering emissions.
In certain locations, demand for clean water already surpasses supply. Several factors, including fast population expansion, urbanization, and climate change, are projected to make delivering safe water even more difficult in the coming years.
Wastewater and water treatment plants now consume a lot of energy. According to estimates, the water and wastewater industries consume between 3.5 and 4% of the world’s total electrical energy. As the cost of energy rises, so do the running expenses of facilities and the cost per litre of water.
Water and wastewater industries require more energy-efficient, cost-effective solutions to assure global water security and limit emissions.
Motor-driven applications, such as pumps, compressors, and fans, are present at every level of water treatment, making electric motors an obvious place to start.
Save more energy with SynRM motor technology
The International Electrotechnical Commission (IEC) efficiency rating system defines motor efficiency categories in several nations.
The categories now span from IE1 to IE4. Each number increase, such as from IE3 to IE4, signifies a 20% reduction in energy losses, implying that the motor is more efficient.
Many water and wastewater treatment plants still use older IE1 or IE2 motors. Many of these motors are still operational, but they consume a disproportionate amount of electricity and put undue strain on the power grid. Furthermore, when the bulk of these motors fail, they are repaired rather than replaced.
This has a higher cost associated with it. This represents a big possibility for efficiency improvement.
Modern motors can be used in facilities to maximize energy efficiency. Synchronous reluctance motors (SynRM) attain IE5 efficiency and are the most efficient motors available today. A SynRM motor typically has energy losses that are 50% lower than an IE2 motor and 40% lower than an IE3 motor.
With current energy prices, the payback period of upgrading pump motors from IE3 models to IE5 SynRM is potentially just a few months
With long-term average energy prices, a facility that changed its pump motors from IE3 models to IE5 SynRM motors should expect a payback period of 11 months.
However, because energy prices are currently significantly above normal, the payback period is even shorter – maybe as little as a few months.
Once the motor has paid for itself, it will continue to save money for the rest of its life. This is due to the fact that the initial cost of a vehicle is only 2% of the total cost of ownership (TCO) on average.
IE5 SynRM motors are offered in the same size and output power classes as induction motors for simplicity of retrofitting.
Benifits of upgrading
One of the key reasons for using IE5 motors is that they protect installations against future legislation. The EU Ecodesign standard will demand a minimum efficiency of IE4 for motors rated between 75 kW and 200 kW in new installations and renovations beginning in July 2023. Europe is the first region in the world to require IE4 efficiency, and others will undoubtedly follow.
Furthermore, using SynRM motors has operational advantages. In pumping applications, for example, they offer a major advantage over induction motors. Slip occurs when the shaft of an induction motor moves slower than the synchronous speed, squandering energy.
Slippage is typical throughout the startup process. To compensate for slip, facilities frequently over-specify induction motors for pump applications. SynRM motors have 0% slip.
As a result, facilities can replace over-specified induction motors with SynRM motors one size smaller, resulting in immediate cost savings.
SynRM motors experience zero slip, therefore facilities can replace over-specified induction motors with SynRM motors one size smaller
Motors can also be used with a variable speed drive (VSD) to improve energy efficiency and reduce energy consumption by 14 to 25%. A drive precisely adjusts the speed of a motor to fit the task’s requirements, enhancing efficiency.
Sensorless flow computation, multipump control, level control, soft pipe fill, dry run protection, rapid ramps, pump cleaning, and anti-cavitation are just a few of the features offered for water and wastewater applications.
These built-in characteristics eliminate the need for extra equipment and allow a facility to function at peak efficiency.
Using modern motors to design advanced pumps
Rodelta, a Dutch company, manufactures pumps for drinking water applications. They contain diffuser technology and are intended to handle big fluctuations in demand. Rodelta specifies ABB SynRM motors to ensure that its pumps are as efficient as possible.
Because they achieve high efficiency across the full operating range, these motors are an excellent fit for the application.
Motors can be paired with a variable speed drive for greater energy efficiency and can cut energy use by between 14 and 25 per cent
Because the pumping stations that use these pumps often run continuously, any efficiency gain results in large energy savings. Rodelta’s new SynRM pumps were installed successfully for the first time at a De Watergroep facility in Leut, Belgium.
The two 75 and 132 kW motors power pumps with capacities of 240 and 350 m3/h, respectively.
Win win situation
Continuing to utilize older, less efficient motors is frequently a false economy; by converting to more efficient motors, facilities can dramatically reduce their operating expenses.
This is especially true as much of the material in older motors can be recycled and new ones may be manufactured from recycled materials, resulting in no new waste when upgrading. Upgrading to efficient motors is critical to meeting demand, and it benefits both business and the environment.
Source: ABB
