Tampa Conducts Home Manager Pilot
By Stephen D. Jenkins, TeCom Inc., and Richard B. Kabat, Tampa Electric Co.
Tampa Electric Co. and TeCom Inc. are subsidiaries of TECO Energy Inc., located in Tampa, Fla. Tampa Electric Co. serves about one million people in west-central Florida. TeCom is a provider of competitive technologies and services for home automation, energy management and utility services. TeCom`s primary product, the InterLane interactive home manager, is being offered for utilities to form closer ties with their customers in today`s more competitive environment.
As a part of TeCom`s development of its commercially available product and a desire by Tampa Electric to gain a competitive edge by implementing the latest technologies, TeCom and Tampa Electric developed a pilot program to demonstrate the InterLane system (see figure). The Tampa Electric pilot program began during February 1995. The pilot test objectives were established as follows:
demonstrate two-way communications (phone line/modem and power line carrier);
demonstrate load control on an isolated (home) and integrated (system) basis;
monitor customer operation of appliances;
simulate time-of-use metering rates; and
demonstrate a user-friendly customer interface.
InterLane hardware and software, along with personal computers, were installed into 140 Tampa Electric employees` residences from August to October 1995. These were initially called “one-box” systems because the InterLane software was installed in the PCs. The interactive control unit (ICU) was installed later in the pilot program. End-use monitoring equipment was installed in 16 pilot participants` residences to verify the accuracy of the InterLane system`s ability to monitor and store whole-house energy consumption data. The system performance test, Phase 1, was performed over a three week period in November 1995. The three major test objectives included:
1. reliability of the system`s software and hardware for continuous use in controlling and monitoring selected appliances;
2. accuracy of the system to measure whole-house and appliance energy usage, maintain clock time and store selected electronic data; and
3. stability of the system to consistently measure and monitor appliance energy consumption.
This test consisted of nine activities to assess the reliability and stability of the home automation features of the InterLane system. The test measured air-conditioning control through an X-10 module, water heating control through a CEBus module, energy usage recording, the quality of collected data and the overall stability of the system. Participants followed daily instructions from a written test plan. After completing each test procedure on a specific system function, the participant was asked to note and record whether or not the system performed appropriately.
The results of this testing indicated greater reliability with the CEBus modules compared with the X-10 modules. Test results of the system`s ability to accurately record whole-house energy usage revealed a very high level of accuracy in measuring energy consumption in kWh and demand in kW. Analysis of the InterLane system`s ability to receive and accurately record sub-metered energy usage data revealed results less than acceptable for billing purposes. Development is presently leading toward improving the measuring module to make it certifiably accurate for billing purposes.
After the completion of Phase 1 testing, Phase 2 of the pilot program involved 60 participants to evaluate the integrated system concepts. ICUs and phone lines with modems were installed in May and June 1996 for Phase 2 of the program.
Phase 2 focused on integrated “utility” functions, including two-way communications, AMR, energy management, load control, load shifting and the application of time-of-use rates. The “Smart Scheduling” feature of the InterLane system was also tested. The feature allows the consumer to use the home automation feature to run certain appliances only when the price of electricity is at or below a specific rate set by the homeowner, or to only use a specified amount of electricity, in dollars or kWh, during that day. This gives the consumer even more flexibility to take advantage of real-time pricing.
Remote meter readings were recorded via dedicated local carrier phone lines from July through October 1996. Functional testing of the power line communications channel with the ICU, meter, personal computer and appliance X-10 and CEBus devices were conducted in July 1996.
Time-of-use rates were developed and tested by half of the participants during the months of August and September. The other half served as the “control group.” Preliminary results from the time-of-use rates testing showed that two-thirds of the group who were asked to modify their energy usage behavior, based on the simulated time-of-use rates, lowered their energy bill compared to what it would have been with the standard residential rate.
This group reduced its energy bills more than 6 percent during the first month of testing and almost 11 percent during the second month. The average savings amounted to about $13 per participant for each month of the testing. The maximum savings one participant realized was $70 for the two-month period. The increased savings during the second month may be attributed to the participants becoming more familiar with the system, the testing and the new rates.
These participants were able to shift load and also reduce energy consumption as they became more familiar with the InterLane equipment and the new rates. By the second month of the rate experiment, the group on the time-of-use rate was experiencing peaks during the highest demand hours of the day which were about 10 percent less than the group on the standard rate.
Looking at monthly energy consumption, the time-of-use rate group consumed about 6 percent less than the other group during the second month of the test. The majority of this load shift was the result of reduced air-conditioning load. While the limited number of participants in the test may not be statistically conclusive, the data provides useful information concerning the receptivity of the participant group to the InterLane system and time-of-use rates.
The “Smart Scheduling” feature of the InterLane system was tested in September 1996 on six participants` swimming pool pumps. The purpose of this test was to demonstrate the reliability of the InterLane system to schedule these devices based solely on a simulated “real-time pricing schedule.” Participants scheduled their pool pumps to run only when the cost of power was at or below a certain rate. This test was very successful and showed the flexibility of InterLane to implement real-time pricing, providing the utility and the customer with more options.
Energy management and load control testing was conducted in October 1996 with two control points per residence: the air conditioner and hot water heater. Three control signals were utilized: priority 1 tested the simulation of water heater-type control, priority 2 simulated “normal summer load control” with the water heater and air conditioning, and priority 3 tested the simulation of “no reserves” load control. An override feature was also tested giving the participant the capability to override only priority 1 and 2 control signals, but not priority 3. InterLane provides the utility and the customer with a new load management function.
Presently, utilities do not receive feedback on whether or not the load control was actually implemented and if a load management credit is really appropriate. With InterLane, the utility has the ability to retrieve what actually occurred from the ICU.
The customer can choose to override the control, with the understanding that he forfeits all or part of the credit. In addition, the utility may choose to apply a capacity and/or energy surcharge to the customer`s bill based on the cost of supplying the additional energy to the customer during the peak it expected to control.
One consideration prior to the performance testing was the possible effect of the Florida weather on the integrity of the InterLane system hardware, especially during the hot, humid, wet summer months when lightning storms are frequent. These elements had negligible effects on the InterLane system hardware and no apparent impact on the system performance. During the testing period, a hurricane came through the Tampa Electric service area. No effects on the InterLane system were noted by any participants, highlighting the weather-proof design and durability of InterLane.
The InterLane system was also tested in a light commercial business environment. InterLane systems were installed in six commercial businesses of various types in February 1996 and testing was conducted in March, April and May 1996. The purpose of this program was to demonstrate the utilization and reliability of the InterLane power manager commercial system in a light commercial energy management application. The power manager uses the same ICU as the home manager but employs EnergyView software to provide demand, energy and power factor monitoring. Testing consisted of recording whole-premise energy usage utilizing the one-box InterLane system, a CEBus meter and a billing meter. Feedback from the participants revealed considerable interest in the system with future enhancements, including sub-metering capabilities.
The Tampa Electric pilot project of the InterLane home manager system was successfully brought to a conclusion in October 1996. The results showed that the InterLane system met the expectations for performance, flexibility and weather resistance. Tampa Electric and TeCom gained considerable information on the use of home automation for energy management purposes, acceptability of time-of-use rates and the effects of implementing time-of-use rates on demand and energy consumption.
Stephen Jenkins is marketing director for TeCom Inc. Jenkins has been with the TECO Energy/Tampa Electric organization for 21 years. He holds a bachelor`s of science degree in chemical engineering from the University of South Florida.
Richard Kabat is the project manager of the Tampa Electric pilot for the TeCom InterLane system. Kabat has a bachelor`s of science degree in mechanical engineering and is a certified manager with the Institute of Certified Professional Managers.
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