The amount of energy consumed in the US to transmit, treat, store and
distribute water is staggering. A few years ago, water and wastewater services’
yearly consumption was estimated to be about 60 billion kilowatt hours (kWh).
Due to population growth and demographics, this figure is destined to increase.
It is also estimated that, from source to tap, it takes about 1,500 kWh for
every million gallons of drinking water. The kWh usage for treatment,
distribution, and storage are significant. To move water, pumping systems are
required and motor-driven pumps present the highest cost for electricity for
water utilities.
Gaining an insight about energy consumption can lead you to implement
energy-efficient practices that can reduce consumption and save on electricity
costs. The best way to find where you can save is by doing a holistic approach
analysis of your energy equipment at your facility. The EPA offers methods on
how to complete an energy audit to establish your benchmark. If you find
yourself lacking the resources to research this, a good place to start is with your
pumping systems. When looking at your pumping systems, you will find that by
implementing a routine, tangible savings will be possible.
How much energy does your plant use?
In many plants, pumps run as often as or even
longer than any other equipment at a facility. Almost 30 percent of the energy
utilized by motor-driven equipment is used to operate pumps. It costs a lot of
money to move water. Thus, energy consumption reduction goals can start by
reducing the number of hours pumping systems operate.
How do you reduce high energy consumption of motor-driven pumps in the water and wastewater treatment sector?
As mentioned above, electrical energy consumption in water treatment and distribution accounts for a major expense at water utility plants. In fact, it’s so high that it ranks second to payroll at some plants. Thus, any manager who wants to improve the bottom line can evaluate when the most economical time to run pumps for full cycles is, and reschedule their off and on setpoints to reduce energy use. This has to make sense to his or her operation; making sure that any new economy pumping routine schedule does not interfere with the overall water management process. An extra benefit to consider is that the less energy is used, the less greenhouse gases are produced. In some cases, this too can be part of a mandate or regulation, which could represent a double win.
What is economy pumping?
Water utilities and water treatment plants are often subject to peak
pricing schedules or variable rates set by electricity suppliers. Economy
pumping deals with the reduction of electricity costs associated with motor
driven pumps by reducing the number of hours pumps run during high rate periods.
Some advanced ultrasonic level controllers <link> have software that
supports energy-saving algorithms with a real-time clock that include daylight
savings capabilities. You can configure the controller’s pumping routines to
run pumps during the times electricity costs less, so that you continually save
throughout the year.
On my next blog, I will cover what it takes to set-up a controller for energy savings, their return in investment and other benefits.
Have you estimated the yearly costs of electricity of your motor driven pumps?
