Efficiency and Demand Response: Twins, Siblings, or Cousins?
Analyzing the conservation effects of demand response programs.
Internet Data Display Many utilities now offer customers energy usage information via the Internet. The data vary from simple monthly data to estimated usage by appliance for residential customers to detailed quarter-hourly usage data provided on a next-day basis. Customers are slowly but steadily taking advantage of their ability to access such data, typically beginning with a few percent of customers in the first year and growing by a few percent per year. In some cases, such as Ameren-UE, more than 20 percent of customers are actively using the utility Web site to obtain data and carry out customer service inquiries. Initial results from analysis of the effects of these programs on total consumption indicate that access to, and use of, the data cause electricity consumers to become more efficient and use less energy. Many utilities have gone beyond just providing monthly consumption, both current and historical, and provide online energy analyses or even more detailed consumption information. For example, over 120 U.S. utilities offer their residential customers an online bill disaggregation tool that evaluates energy use to show how much each appliance or end use is consuming, and also makes recommendations on where to cut energy use, and by how much.
For commercial customers, the largest and most comprehensive program in place today is in California. During California's 2001 energy crisis, the state legislature approved funding to provide smart meters to all customers with peak demands above 200 kW. Assembly Bill 29X provided $35 million from the state General Fund to the California Energy Commission to install either time-of-use or real-time electric meters for utility end-use customer accounts with peak electric demand levels of 200 kW or more. The energy commission determined that installing real-time, or "interval meters," was the best use of public funds. Real-time meters contain electronic components enabling the utility to read them remotely and then communicate the collected energy-use data to a utility's billing system.
Deployment of real-time electric meters implements one of several technological solutions available to ameliorate California's electricity crisis. To meet the mandate of the legislation, the commission implemented its real-time metering program in May 2001. Through contracts with California's electric utilities, the program provided approximately 23,300 real-time meters and associated electronic communications equipment, enabling customers to view their hourly load profile and energy use either over the Internet or on a real-time basis. 10 The program included all of California's major utilities and was designed to motivate at least 500 MW of peak-demand reduction during its first year of operation.
The utilities provide customer access to usage information via the Internet using an integrated software package, including supporting hardware and software and professional services. Meter data from the previous day is sent to these systems for display to the customer the next morning. Customers have a variety of preformatted reports from which to choose and may also develop custom reports. These reports can be generated for specific time frames, such as the last 24 hours, the last month, and the last year. Customers can view charts comparing two different time frames for a