Green Power Quality
Two issues involving electric power are escalating simultaneously: consuming and producing electric power in a more “green” fashion and the need for a better quality of power. Green power, as splashed over various headlines, has many meanings, but it typically relates to being more efficient in electricity usage and more environmentally friendly in its production. However, quality power or power quality is a much less publicized topic.
Sensitive electronics now appear in everything from the toaster oven to the controls that manage the most sophisticated manufacturing processes. It is in the commercial and industrial areas that power quality is a serious problem. If a toaster oven does not work properly because the voltage is too high or low, one can probably still make toast, maybe not automatically. However, if a large ice cream production line shuts down for 30 minutes due to a drop in voltage lasting less than a second, the result might be tens of thousands of dollars in revenue melting away. While poor power quality might be nuisance to the average homeowner, it costs U.S. businesses billions of dollars in lost revenue every year.
Many businesses with huge bottom line dollars at stake invest heavily to avoid the costs incurred when the quality of their power affects their operations. But, this is the point at which the concepts of green power and power quality can be at variance: some solutions for maintaining power quality may be very “non-green” by substantially increasing the consumption of electricity.
Here is an typical example:
A mid-size manufacturing facility averages 50 power quality events per year that can cause their production to stop. Each time production stops because of these events, it costs $10,000 in lost material, labor and profit. Two solutions with the same first cost are available to correct these power quality events, but neither will solve 100% of them. The solutions are:
Solution A
Average events corrected per year: 48
Efficiency: 85%
Annual energy losses: $70,000
Solution B
Average events corrected per year: 46
Efficiency: 99%
Annual energy losses: $5,000
While Solution B is might not be quite as effective, it saves $65,000 per year in energy losses and $45,000 in total even with the two extra events taken into consideration.
In many cases, the efficiency of power quality solutions is given little consideration and the end-user winds up solving one problem but creating another: better power quality but much higher energy consumption.
Being “green” by reducing energy consumption in today’s marketplace is not only great for the corporate image, but for the bottom line. Careful selection of energy efficient power quality solutions can yield substantial financial and other benefits besides delivering the necessary quality of power.