Enerdynamics

by Bob Shively, Enerdynamics President

In our latest blog post, What Is the Smart Grid?, we discussed three applications for the Smart Grid. One such Smart Grid application is performing the functions that transmission owners and distribution utilities do today but simply using new technology to do it more efficiently and reliably.  This post elaborates on this application by providing an example of how implementation of Smart Grid technologies can improve reliability and asset utilization for an electric transmission company.

Traditionally, system schedulers used models to estimate the capacity available on transmission lines given expected weather, system flow, and other factors.  Using estimated data and modeled conditions forced operators to be conservative since they had to be careful not to exceed physical line limits.  This means the true physical capability of lines often was underutilized.  By installing and utilizing technologies that allow real-time monitoring and visualization of line conditions, operators can more fully use the capability of existing transmission lines.

So what technologies allow real-time monitoring?  These include monitoring devices that allow views into the condition of the power flowing on transmission lines as well as physical monitoring for factors such as line tension, line temperatures, and line sagging.  This could be as simple as video cameras on top of towers that allow real-time visual monitoring for sag or may be as advanced as widespread installation of phasor measurement units (also known as PMUs).

PMUs allow visualization and monitoring of the magnitude and phase angle of system voltages and currents.  Coupled with analytical software, this data allows operators to analyze voltage, current, reactive power, and frequency at multiple locations throughout the grid.  Given this knowledge, they can determine exactly what can and cannot be done on the transmission grid based on actual conditions. Thus, they can often identify problems before they occur and proactively solve the issue.

For a good discussion of how PMUs have helped one transmission owner, Southern California Edison, see the article “Phasors Point the Way” on tdworld.com.

by Bob Shively, Enerdynamics President

Enerdynamics instructor Dan Bihn and I spent 3 days at the IEEE conference on Smart Grids this past week in Anaheim. One of everyone’s key questions was “What is the Smart Grid?” We learned there is no clear consensus, although everyone seems to agree that we already have a somewhat smart grid, so what we’re really talking about is making a Smarter Grid. What this entails is pushing digital communications, monitoring, control, distributed intelligence, generation capabilities and storage capabilities deeper and deeper into the grid from generation into transmission, distribution and even behind the customer meter.

For instance, just a few years ago energy companies could remotely monitor the position of switches in large transmission substations but not anywhere else. Now they may have that capability extended to distribution substations and maybe even to switches out on distribution feeders. Once AMR meters are installed at the customer facility they can now remotely monitor conditions all the way to the customer meter. Such capabilities can be used in many ways.

Dan and I came up with three different broad categories of applications. It gets confusing because all three use common technologies and, depending on who you talk to, all three get called the Smart Grid. Here are the three:

1. Doing the functions that transmission owners and distribution utilities do today but using new technology to do it more efficiently and reliably
2. Enabling a host of new services that allow customers to more actively participate in electricity markets through use of demand response and distributed generation
3. Enabling micro-grids, which are small localized grids that can run in isolation but can also be interconnected into the wider grid

In future blog posts, we will explore these categories in more depth, and these concepts will culminate in Enerdynamics’ new one-day seminar, Smart Grid Overview, which will be available in Houston on April 20.