Note from the Editors: The following is the fourth in a series of guest articles by experts from across the broadband ecosystem. Mark Francisco, Director Engineering Home Services, Comcast New Media Development, has been leading an engineering team centered on using the best of Comcast's data, telephony and video resources to seamlessly provide additional services to their customers. Mark currently serves on the CableHome Certification Board. Previously, he led the systems integration of CDMA Cellular Phones for Motorola and developed microwave communications hardware for satellites. Mark has a BSEE degree from Rutgers College of Engineering and an MSEE degree from Drexel University; he lives with his wife and two children in Clarksburg, NJ.
Broadband Lifestyle Interfaces – Energy Management
With more than 80 million households in the United States potentially able to connect to an always-on broadband infrastructure, there is substantial potential for operators to deliver innovative new services to the home. For instance, a service that enables a residential consumer to more effectively manage their energy consumption may be offered without the prerequisite of a high-speed Internet service subscription. This “Broadband without Internet” service model is well suited to telemetry and control applications, which rely on a persistent broadband connection, but do not require high speed or the other features associated with the Internet, such as e-mail. These types of services are developed to provide benefits to consumer with little or no cost while also providing value to the service provider, in this case the electric utility.
An energy management service interconnected via broadband communications can provide a method of controlling demand during critical consumption periods as an alternative to additional energy generation. This form of capacity will provide benefits to both the utility and consumer. As a result, services such as these can potentially make the existence of a broadband connection in the home as essential as electricity or the telephone.
Description of an Energy Management Service
Energy management equipment allows the homeowner and electric utility to monitor and control the appliances that are responsible for the majority of the electric load in the home, e.g., air conditioning, water heaters, pool pumps, etc. With a persistent connection provided to these devices as well as the house electric meter, energy demand can be monitored almost real-time. The homeowner can also use this capability to automate their comfort control systems and other high load appliances. Additionally, the homeowner has access to the system through equipment interfaces in the home and also remotely via the Internet, where detailed reports specific to that home can be viewed. The utility can also use a secure web based interface to utilize these same capabilities at an aggregate level, within a single location and over many locations, to curtail consumption within the guidelines of the customer service agreement.
Roles and Benefits
Participation in a demand-side management program allows a consumer to have greater control over their comfort systems and high-energy consumption devices. Because the service is provided over a broadband connection, the homeowner has access to instantaneous data, both within and outside the home. Additionally, it is possible for the homeowner to decline to participate in a given curtailment. Benefits of participation in the service include:
By allowing the homeowner to opt in to specific curtailment programs, the user application permits a homeowner to tailor the extent of their participation in demand-side management to their unique needs and comfort scale. In addition, homeowners may opt out of specific curtailments by canceling them once they have taken effect. Of course, a homeowner’s cost savings or other incentive would vary depending on their chosen level of participation.
Electric utilities are responsible for generation, transmission and distribution of energy to their customers. Their infrastructure must be capable of supporting peak demand, e.g. supplying power for air conditioning on a hot August afternoon. Regionally, homes have consumption patterns that typically peak during a specific portion of the day. These peaks may shift seasonally. The summation of these peaks requires a grid capable of far more capacity than the average consumption requires. For example, during warm days in the summer, power grids and generators may be operating at or near maximum capacity during the afternoon peak cooling period. Generation to support this peak demand may require the construction of additional power capacity, the use of more costly “peaker” power plants, or spot purchases of energy from intrastate transmission companies, often at very high prices.
Demand-side energy management systems assist in reducing demand for energy at these peak times. Through the monitoring and control capabilities contained in the installed hardware and associated software, curtailments can be issued to reduce peak consumption, reducing the difference between peak and average demand. Often, curtailments cause load-shifting patterns, where the peak load is shifted to a below average usage period later in the day. This results in greater efficiency for the utility and reduced strain on generation assets. The goal is to turn the sharp, peak demand consumed in a few short hours of the day into a level, sustainable consumption throughout the day.
Curtailments can be issued through a combination of events: by temporarily shutting off discretionary loads such as hot water heaters and pool pumps and/or by making changes to the environmental thermostat control set points. The system is designed to change a homeowner’s thermostat setting in small and gradual increments to minimize the perception and impact of the curtailment. In summary, the utility can use an energy management service as an alternative to activating costly “peaking” power plants or to the purchase of expensive spot market power from other plants. Potentially the stress on local transmission and distribution facilities may be reduced through monitoring and targeted curtailments.
Broadband Service Provider Benefits
The broadband access provider is responsible for providing a secure and managed network connection to the home. The energy management service may be delivered to the home without requiring the homeowner to subscribe to high-speed data services. Therefore, the service provider gains the ability to provide a broadband service to a home independent of the homeowner’s choice to subscribe to any direct product offerings. This represents a new revenue opportunity and does not relate to or interfere with the ability to sell traditional products, such as high-speed Internet.
Components of Demand-Side Management
The system as currently implemented consists of an energy gateway, one or more communicating thermostats, and optional subnet metering switch modules. The energy gateway is comprised of a DOCSIS cable modem integrated to a gateway. The modem is configured specifically for the data associated with the energy management service. The gateway contains an embedded processor and control applications and the radio components necessary to communicate with the metering and control devices. The communicating thermostat is similar to a conventional programmable thermostat, but with the capability to transmit and receive temperature, heater or air-conditioner mode, and set points data and commands to and from the gateway.
The solution also includes a meter and switch device called an LCM (Load Control Meter) that may be installed in any home branch circuit to create a separately controlled and metered subnet. The LCM allows control of dedicated high-current loads such as electric hot water heaters, pool and spa pumps.
A communicating electric meter is included, allowing monitoring of whole house consumption and remote meter reading, which may provide an additional benefit to a utility not currently implementing such a capability.
All in-home elements can be installed by the energy management service provider, including the broadband access gateway.
The infrastructure components in the system include a data aggregation server, security server and web-based application server. The radio communications protocol has been optimized for range and reliability at a low data rate.
Comcast New Media Development and its partners, PECO Energy Company and Invensys have been conducting a technical trial of a demand side management product, “GoodWatts(TM)”, since the summer of 2002 in Southeastern Pennsylvania. Approximately 100 homes were outfitted with the system for the purposes of technical evaluation and to begin measurement of the effects and impacts of demand-side management. Invensys developed the communicating hardware and application software and additionally manages the energy data, providing it to both the utility and homeowner.
Trial participants have reported favorable experiences, and have liked the benefits of conservation, and remote access to their comfort control systems. Curtailment events during the trial have successfully reduced consumption in the homes and are a preliminary indicator of the efficacy of demand-side management. Network traffic going between the homes and infrastructure servers has been measured and determined to be small enough to allow large scale deployments without impacting high-speed data users. Efforts are underway to secure a larger scale market trial in order to more fully quantify the impacts of demand-side energy management.
The introduction of broadband monitoring and control capabilities into the home may allow for the future extension of other benefits to the homeowner. The ability to remotely provision software into the embedded processing gateway allows additional applications to be easily installed. In the future, new and existing appliances will be provisioned with integrated communication capabilities that enable additional applications for automation and remote monitoring services such as breakdown detection, lighting, appliance timing, and home security and safety applications.
A demand-side energy management product is a tool for both the electric utility and homeowner that provides for flexible control of power consumption. Use of a secure and managed broadband connection adds the ability to verify the effects in real-time and benefits the broadband service provider by increasing their service reach to homes, beyond traditional products. As a result, the electric utility gains operational efficiency, the customer benefits from greater control and potential for conservation, and the broadband service provider obtains new service revenue.