Electric power's five biggest challenges, Part One: Balancing supply and demand in the face of complexity



Quick Take: A decade ago, U.S. Department of Energy (DOE) primed the smart grid pump with a Grid Vision workshop in Washington, DC. Many of today's smart grid concepts and policies can be traced back to that seminal meeting.


Now DOE has partnered with the GridWise Alliance (GWA) to hold four regional workshops followed by an Executive Summit in Washington, D.C. to once again develop a stakeholder-driven vision of the future grid. As a participant, I received background materials in advance.


Those materials included thoughtful discussions of five future scenarios. Or, if you prefer, five future challenges. They did such a good job of framing the issues that I asked permission to share them with you in a series of articles.


Part  One in the series talks about an electric power system's most fundamental job -- namely, balancing supply and demand. At the end, you'll find a handful of questions. I invite you to use the Talk Back form at the bottom of the page to leave your own answers and opinions. When the series has finished, I will share the comments with the DOE for their consideration as they set the agenda for the next 10 years. - Jesse Berst


By Steve Hauser and Becky Harrison


Today, transmission grid operators must ensure there is enough power generation to service the load, both in terms of wattage and volt-amperes reactive (VARS). To do so, the operator continually adjusts central generation.


Some systems can also use a limited amount of demand response (DR) as another resource to keep supply and demand in balance. For residential DR, the operator typically sends a signal to switches on customers’ air conditioners, water heaters, and/or pool pumps.  The switches then cut off the load completely, or cycle it off for a given percentage of time in an hour. This simple but effective mechanism allows the operator to ride through a few critical peaks as an alternative to providing additional generation.