No one wants to be responsible for building a system that is under-sized. But when equipment is oversized, energy efficiency drops, reducing its cost-effectiveness.
This is commonly seen with pumps. Everybody wants the pumps to feed the maximum rate of air or a substance to the process. But what if a control, such as a valve, is placed to reduce flow to the optimal rate and that valve is partially closed nearly all the time? The pump was over-designed. It is operating at a continual high rate and then additional equipment, using energy, damps down the rate. This is like always stepping hard on your car accelerator and then quickly pumping the brakes.
Not only does this cost your facility needless energy usage and demand, but the inefficiency often leads to overheating and increased wear and tear, reducing the life of your equipment (raising long-term capital costs) and increasing O&M costs, too.
This is especially a problem in older systems, which are often over-designed as a cultural matter. The design engineer would recommend a pump with a capacity 20% greater than needed (“just in case” things change); the vendor would recommend a specific pump that was 20% greater than that for the same reason. This was tolerated as the cost of such over-conservatism – energy – were quite low back then.
The solution for many pumps and fans is to determine the proper size based on the worst-case usage and to utilize a variable frequency drive (VFD). A right-sized pump for worst situations plus VFD to adjust the usage for need can reduce energy usage for a given pump or fan by 50% or more and reduce wear and tear. In addition, many utilities and state incentive programs will pay you part of the cost of its purchase.
For pumps alone, they may account for up to 60% of total electrical energy usage in an industrial facility. 58% of a pump’s life cycle cost is energy. Therefore, by optimizing a pump system, annual energy consumption can be reduced by 30-50%. And this does not include increased O&M costs caused by wear and tear.
This mathematics is also true for other systems, such as HVAC fans, common in many more facilities.
CCES has the technical experts to help you evaluate your pump and fan systems and help right-size your systems to save you much in energy and O&M costs. Contact us today at 914-584-6720 or at firstname.lastname@example.org.