New 'Green' Product - High-Efficiency, Variable-Speed Pumps from Wilo and Grundfos

[Dover]

Pumping uses a tremendous amount of electricity. In looking at efficiency of hydronic heating systems, we have long focused on the fuel used to heat the water being circulated, without paying much attention to pumping energy. Fortunately, that’s beginning to change.


Residential Stratos ECO circulators from Wilo.

Two of the world’s leading pump manufacturers, Wilo (pronounced “veelo”) from Germany and Grundfos from Denmark, have introduced to North America advanced, high-efficiency, variable-speed, ”smart” pumps that can reduce pumping energy use by over 75%. Wilo offers the Stratos for commercial applications and the Stratos ECO for residential applications. Grundfos offers the Magna line for commercial applications and the Alpha line for residential applications.

Smart pumps

The Wilo and Grundfos smart pumps share two important features. First, they have integrated variable-frequency drives (VFDs) to modulate the pump speed or flow rate. They use a very clever technology to set that flow rate—analyzing their own rotational speed and current draw and, from this, computing where the pump is on its “pump curve” and optimizing pump speed accordingly. For larger pumps, separate VFDs have often been added; the revolution here is that the VFD is directly integrated into the pump and that it’s available for smaller pumps.

Second, these pumps have permanently charged, electronically commutated motors (ECMs) that reduce energy use by about 50%, according to Rick Fredette, of Urell and Company, the Northeast sales rep for Grundfos. He notes that pumping accounts for about one-fifth of the electricity used in most commercial and institutional buildings, making these savings very significant.

In addition to these features, the Grundfos Magna and Alpha circulators also include a unique “AutoAdapt” smart logic that automatically and continuously adjusts circulator performance to match the changing needs of the hydronic heating system. According to Fredette, AutoAdapt looks at the system every seven seconds, learns the operating patterns, then optimizes performance.


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http://www.buildinggreen.com/auth/article.cfm/2010/8/30/High-Efficiency-Variable-Speed-Pumps-from-Wilo-and-Grundfos/