I spent some time last week down a country road, watching the local power. I watched three phases that were greatly out of balance. I observed trapezoidal wave forms. We could see the home appliances of everyone else on the road, as they each turned on and off.
Together, we watched the power coming into his lab. They were his neighbors, and he knew them from observation. He could relate when they changed their appliances, and how they lived their lives. He could tell from the patterns how they affected the shared local electric distribution circuit. There were some especially odd patterns, second level harmonics that caused some unusual recurring spikes. It wouldn’t be hard, simple machine learning, really, to learn these special patterns for some types of equipment, and then to search for them.
This is all so much easier than it was even a couple years ago. Affordable gigahertz sampling is no longer cost prohibitive. Industrial espionage can be done from across the street. Soon private detectives will be able to read the activities in houses from down the street, using only a power connection, pattern matching against an on-line database, and a little creativity. Your house and business is now an open book, with or without the participation of utilities.
This technology was not built to look out, however. Monitoring and analyzing the distribution feed is a mere side effect of the system I was checking out. The purpose of these systems is not to spy on the distribution system, but to defend against the distribution system. What we could see on the samples is also felt by the building.
The purpose of this monitoring is to fix the power inside. Each phase of power is simultaneous corrected to near ideal wave forms. The effects inside the building are extraordinary. When supplied with an ideal power wave, electric motors become audibly quieter. While that alone makes an industrial space pleasanter, it reflects an underlying reduction in vibration and in generated heat. At the same time, the motor begins to operate at its faceplate output.
This is what I mean by defense against the distribution system. Excess vibration, and the associated noise and heat, are caused by the noise on the electrical supply, by wave forms that are less than the ideal. Traditional power conditioning systems often create trapezoidal or triangular wave forms—they may protect from spikes and sags, while they increase wear and tear. It’s too early to predict how much ideal power forms will extend the life of equipment, but reduced noise and reduced heat are strong benefits on their own.
While one can hear the change in motor operation, florescent lights and digital equipment benefit as well. Long time readers of this blog know that my house is beset by something that causes even my incandescent lights to fail in clusters. Having watched the power on this nearby local distribution loop, it seems likely that I have seen the answer, even while all parameters are “within spec for home distribution.”
The plan of course, is for the local distribution to get worse. While we watched, we saw changes to power on the entire loop when the charging of a single neighbor’s electric vehicle began. Even the best solar panel installations affect these wave forms, and most installations are far from the best. The effects not only damage neighbor’s equipment, but they may increase metered power use for those neighbors as well.
Defense from the grid, especially from the smart grid is an important new market. Distributed energy resources are in all our future, and they make such defense more important.
An allied outcome of this defense is that the view from the outside is obscured. The systems behind the power controller cannot be inspected as we inspected the neighbors. Unbalanced power use, that is, power unevenly spread across the three power phases is balanced on the outside of the controller. Power factor is optimized. This ideal power load reduces metered power, often substantially. The operation of individual motors and digital systems looks from the supply-side as a single ideal consumer. Energy-use privacy is protected and restored.
As consumers, we don’t yet know how to think about and use this kind of product. As smart energy, distributed energy resources, and electric vehicles become more widely deployed, we will want to learn.