Peak-to-average electricity demand ratio rising

According to US EIA, “the highest peak-hour electric demand for the year in 1993 was 52% above the hourly average level while in 2012 peak-hour demand had risen to 78% above the hourly average level.”

So what does this mean and what are the implications? Well US EIA says:

  • “generators called on to meet peak-hour demand are running fewer hours and/or at lower output levels the rest of the year”
  • “likely cutting into generator revenues and increasing the importance of capacity market payments to generators”

US EIA demonstrates to the reader the changes in hourly demand between 1993 and 2012 using a load duration curve.  Some possible reasons for the change that are discussed in the article are:

  • Lifting peak demand levels in the summer relative to average levels for the year
  • Energy efficient electrical equipment and appliances that reduce average electric demand
  • Shifts to a more service-based economy


Check out the Load Duration Curve and Video.


Smart Grid: Austin Energy: A real-life advanced distribution management system (ADMS)


“Austin Energy hopes their ADMS will help them achieve a number of energy efficiency, profitability and customer service goals by 2020, such as”:


  • 35% renewable energy component in its energy mix
  • The deployment of 200 Megawatts (MWs) of solar power, with half of that being installed on roof tops
  • An 800 MW peak demand reduction
  • Overall, customer satisfaction of 82% as measured by a variety of surveys
  • Maintain reliability goals of  System Average Interruption Duration Index (SAIDI) of 60 minutes and of System Average Interruption Frequency Index (SAIFI) of 0.8 interruptions
  • All of these goals must be achieved while meeting affordability measures of no more than an average 2% rate increase per year and ensuring that the average residential bill is in the bottom 50% of the residential bills in Texas.

article by smart grid technology

Care Is Needed In Economic Analysis Of Energy Upgrades As Electric Rates Change

“Utilities charge for peak demand to cover fixed costs related to capacity they must build and maintain to generate, transmit, and distribute electricity, regardless of how many kWhs are actually used. In many areas, 20 percent or more of such capacity is used less than 100 hours a year, typically when it’s hottest outside. During the rest of the year, much of it is in standby mode, but must nevertheless be ready to serve on very short notice. How to charge for those costs varies among the thousands of U.S. utilities. Many levy a fee based on a customer’s peak kW seen each month multiplied by a regulated $/kW rate that may vary seasonally. We call that a “peak demand charge.”–By Lindsay Audin