Buy the most efficient motor available, and keep it clean.
Electric motors account for nearly sixty percent (60%) of the global electricity consumption! Comparing the total life operating cost with the first cost is instructive. Typically the CapEx (capital cost) is only 1 % of the total cost of ownership (e.g. 20- 25 years lifespan for HVAC equipment) Additionally, during the first year of operation a motor will consume electricity to cover its CapEx value, considering the life time cost purchasing the most efficient motor is very cost effective investment.
Look after your motors
Thirty years ago I visited facilities with a real boilerman, he did more than just operate the boiler, but that was his title. Perhaps boilerperson would be politically correct today. Back then, he was a rare breed, and fiercely proud of his domain. Upon entering any plant room you were greeted by gleaming plates, gauges, copper and brass polished bright, polished cladding, the room itself fit for dining, but not today cleanliness has gone the way of the dinosaurs.
One popular and possibly most annoying pastime of today’s fitter is over-painting equipment labels, indeed it’s seems to be compulsory. Yet it still holds true today, a clean facility will have fewer problems.
One obvious and often overlooked matter is electric motors, simply keeping the cooling fins clean maintains the heat transfer efficiency from the motor fins to the surrounding air. The failure to follow simple maintenance procedures can be costly, allowing motor winding temperature to exceed the manufacturers rating by 5 DegC halves the operating life of the motor! Keep the plant and motors clean.
— John Herbert, consultant, energyLAB