A VFD for efficiency - Emotron regulates Vitens’ deep well pump with less energy

Vitens, the largest drinking water supplier in the Netherlands, has 5.4 million customers in the provinces of Friesland, Overikssel, Flevoland, Gelderland and Utrecht, and about 20 million additional customers in countries around the world. Their job is to ensure the purity of drinking water every day, around the clock, and they consistently surmount this challenge!

The Drive for efficiency

Vitens’ customers have come to take safe, affordable drinking water for granted, but providing clean water in an energy-efficient manner is no simple task. Drinking water usually travels significant distances and goes through many pumping, filtration, storage and other steps before it flows from a customer’s tap. This not only has to work reliably and flawlessly; it also consumes a lot of energy.

Clean water in an energy-efficient manner

tough operating conditions

In order to reduce the energy consumed with valves that regulate the flow of the deep well pumps, Vitens began looking for a more efficient solution. It was not easy, because the equipment has to operate in quite tough environments, characterized by moisture, dirt and sand, big temperature variations, space limitations and other challenges. Any new solution needed to match these demands.

Vitens approached CG Drives, which has a reputation for industrial technology that can withstand challenging environments. Could CG offer a solution that would function well under such tough conditions? Moreover, could they provide a solution that would also enable Vitens to regulate its pumping stations for significantly less money? CG Drives & Automation proposed a pilot installation involving one pump at the Fledite Pumping Station in Zeewolde to find out.

Pumping stations located in small buildings and cabinets over the wells

Benefits and return on investment

The main benefit achieved by the Fledite installation was in energy savings. With its full complement of thirteen CG-regulated pumps operating, at 7 million cubic meters of annual pumping volume, about 250,000 kWh per year are being saved. At a current electric rate of 12 eurocents per kWh, this gives an annual savings of €30,000.

The equipment and installation costs totaled about €85,000, which means that the installation at Fledite will pay for itself in less than 3 years at present energy prices and water pumping rates. If either rate or volumes increase, it will pay back even faster.

Not only are the numbers great, an additional benefit is the increase in reliability that the CG solution contributes to the drinking water supply. Add to this the increased uptime at the well heads and pumping stations, saved working hours, longer equipment lifetimes and fewer managerial headaches, and it is clear that Vitens has made very sound investment indeed!

Emotron variable frequency drives (AC Drives) in combination with an all-pole filter.

The Skövde wastewater plant – a satisfied CG customer

The Skövde wastewater plant is very satisfied with the installation of CG's AC drives and support available with the new solution. The solution has been in operation for over two years and it proved itself straightaway. It rained the day it was installed, and the customer saw its effect already on the first day. ”CG's AC drives are very good; their support and service is outstanding,” says Tommy Mårdberg, from Skövde Municipality. An installation with a similar solution is planned for Hjo.

A complete solution

A high-efficiency, durable, complete solution was installed for the pilot, enabling CG to successfully demonstrate that the job could be done using less energy, but with at least the same reliability and degree of control. Emotron variable frequency drives (AC drives) were used, in combination with an all-pole filter for protection of the special deep well pump motors. Frequency drives (AC drives) are connected to the pumps, regulating their speed, ensuring the needed flow of water. Since the earlier use of motor valves had accounted for much of Vitens’ energy loss, the switch to variable frequency drives (AC drives) reduced energy consumption considerably.

Summary
Customer The Vitens water supply company’s Fledite Pumping Station in Zeewolde, Netherlands
Challenge To decrease the energy consumption involved in regulating valves in deep well pumping systems while increasing equipment reliability and durability
Solution The Emotron frequency drives (AC drives) for pump regulation, along with associated control equipment, cabinet, and pump filters
Solution Benefits
Emotron AC Drives
  • Assurance of a safe, dependable drinking water supply for Vitens’ customers
  • Lower energy costs
  • Rapid investment payback
  • Greater equipment durability and reliability
  • Longer lifetime of equipment
  • Reduced labor and management costs