Tuesday, June 21st, 2016
Power Quality (PQ) is an interesting issue that I’ve been close to for quite some time. The problem has been discovered, debated, defined, solved, re-defined, lost, re-discovered, debated, etc… Manufactures, consultants, service providers, regulatory bodies and governments have explored, used and abused the topic. I should include myself in the group. I’ve provided consulting services, sold systems to monitor and report on PQ issues and taught classes on the subject. However, one of the most critical aspects of this subject is seldom, if ever, addressed. Often, when a manufacturer is selling a product to mitigate PQ problems (or consultant providing analysis and recommendations), the focus is on down time, damaged equipment, disruption to schedules, etc. Although these are typically the main issues, when these costs are estimated, there’s a large component missing.
That missing component is lost or wasted energy. It’s particularly significant in process industries where the product, which takes days or weeks to perfect, must be thrown out because of a loss of clean room integrity. Yet, it’s also significant in many others environments. What I find odd is that most assessments don’t include this cost. In one study we performed, the wasted energy was quantified and alone would have supported significant investment in mitigation.
With the renewed interest in efficiency (required to reach sustainability goals), I believe it’s time that end users take a hard look at the issue. Many of the old PQ problems have resolved themselves (not without smart people doing hard work). The advance of power electronics has given us unity power factor power supplies, more robust equipment, etc. Without renewing the debate or engaging in redefinition mentioned above, it’s clear we still have PQ issues and we need to get better at targeted solutions. This requires better data and better analytics.
As Micro Grids and other smart grid technologies gain momentum, I suspect this will become more important. Consider a Micro Grid which depends on battery storage to ride through a switching operation during utility outage. The available energy in the battery at that moment is very valuable. In this scenario it is EXTREMELY important to make sure your system is efficient AND unnecessary discharge of battery energy is minimized.
If you agree, let me know. If not, I’d really like to hear why.