As we near the end of the first decade of the 21st century, the world sits on what vice president-turned-environmentalist Al Gore famously called in the documentary, An Inconvenient Truth, “a tipping point.” A point in time when increasing greenhouse gases could lead to a “planetary emergency.” Adding to the dilemma, the world's growing population and a growing global thirst for energy stands to escalate the situation, culminating in a perfect storm of economic, social and environmental pressures on scarce energy resources.

In nearly every country, researchers are projecting that existing energy production capabilities will fail to meet future demand without new sources of energy, including new power plant construction. According to a recent report from the North American Electric Reliability Corporation (NERC), electricity demand in the United States is expected to grow by 141,000 megawatts in the next decade. Yet, only 57,000 megawatts of new resources have been identified, leaving a shortfall of 84,000 megawatts — an amount equivalent to 160 large power plants. Globally, it is predicted that more coal-fired power plants will be built to meet increasing demand due to their cheaper economics. Alternative sources of energy, including clean energy technologies such as wind, solar and fuel cells also are being investigated and brought on-line to increase the global energy supply. However, these supply-side solutions ignore another attractive alternative: to slow down or decrease energy consumption through the use of technology to dramatically increase energy efficiency. The cleanest energy is the energy not generated in the first place.

One viable technology solution to this energy crisis is ZigBee — a global wireless standard based on IEEE 802.15.4. As an established standard, it is now being used by companies as the foundation for the home area network (HAN) to give residential consumers an unprecedented way to improve energy efficiency and utilities gain the ability to create load management programs with minimal customer inconvenience. Such networks function by wirelessly connecting dramatically different devices like utility meters, thermostats, lights, HVAC systems, and appliances. As a result, they provide the “last foot/meter” connection needed by innovative utility companies to have a new dialogue with their customers in support of energy efficiency and other advanced metering infrastructure (AMI)-powered initiatives.

A closer look

AMI is defined as the communications hardware/software and associated system/data management software that forms a network between advanced meters and utility business systems. It allows collection and distribution of information to customers and other parties like competitive retail suppliers, in addition to the utility itself. More important, it connects the utility to a HAN typically comprised of ZigBee-enabled devices including appliances, thermostats, water heaters, pool pumps, and more. This network of ZigBee devices is easy to connect and allows users to customize and monitor their energy consumption in an environment where devices communicate with each other and can connect to the outside world to enable remote access and control either by the utility, a third-party service provider or the customer.

With AMI and ZigBee HAN devices, customers will gain complete daily, hourly or even “by the minute” control over their energy consumption, thereby empowering them to save money. ZigBee allows consumers to set their thermostats, or to turn their air conditioner or heater on or off based on energy pricing as well as comfort. A pool pump or hot water heater can also be programmed to turn on or off only at specific energy price points, saving even more money. Lights controlled by ZigBee wireless technology can be set to automatically turn off during peak demand and only come on when the consumer arrives home. They can also dim to predefined levels when energy is more expensive or when sunlight is bright. Should a consumer forget to program lights for security, they can even be remotely and securely accessed via the Internet and programmed appropriately.

From a utility perspective, when demand for electricity is high, a message can be sent to customers informing them of the high demand and that real-time electricity prices are increasing. The customer then has a choice. They can do nothing and continue using their current level of electricity at a higher price. Or they can reduce electricity usage either manually or by allowing the utility to selectively adjust usage automatically. This two-way interaction is called confirmed demand-response. Research shows that residential demand-response adoption rates of as low as 30% could provide significant consumer and utility savings. Another study estimated that the potential economic benefits of demand-response activities from demand bidding could range anywhere from about $80 to about $800 million annually, depending on the level of system need. Economic benefits from emergency demand response range from $85 million to more than $300 million annually.

Analysts predict that advanced metering systems could bring customer usage and meter data into new utility “central nervous systems.” AMI and ZigBee provide more efficient customer management as well as the added advantage of new tools and real-time data to react to emergencies. For example, should a power outage impact an area of homes or businesses, utility companies can pinpoint this information down to a single fault area within seconds. Using the data collected from in-building networks in the affected area, the utility can reroute grid feeds using remote switches to isolate the fault and restore service to the majority of affected customers within minutes all without a truck roll. By deploying repairmen in a targeted manner during widespread outages, power can be restored much faster than was previously possible. Minimizing power disruptions also reduces the risk of lost revenue and avoids punitive fines or damages for the utility.

Setting energy efficiency expectations

Policymakers worldwide are now looking to create alternative solutions like AMI that improve energy efficiency. In virtually all cases, ZigBee has been identified as a technology key to their common vision of energy management and efficiency. Here are just a few examples:

• The GridWise Alliance is a collaborative venture between the U.S. Department of Energy and public and private stakeholders who are rethinking the U.S. electric infrastructure. Their mission is formidable: change the way energy is planned, built and operated. Their vision is of an electric system that integrates the infrastructure, processes, devices, information, and market structure so that energy can be generated, distributed and consumed more efficiently and cost effectively; thereby achieving a more resilient, secure and reliable energy system.

• In the United States, the U.S. Energy Policy Act of 2005, and initiatives in California, Texas and several other states urge or require improved energy efficiency. The state of California's title 24 2005 building energy efficiency standards mandates programmable communicating thermostats to all residents and obligates utilities to devise energy efficiency strategies to make use of this connectivity. In May 2007, the Public Utility Commission of Texas set forth rules on features for AMI and set minimum technology requirements, which included a requirement for HAN capabilities.

• In March 2007, the European Union (EU) Summit met in Brussels and adopted a road map for an integrated energy and environment policy based on clear targets to ensure less fossil fuel usage along with energy efficiency measures. During the summit, energy performance standards and certification requirements were established for buildings that would allow technology to play a key role in using energy more rationally. Currently, the EU's framework programs for research and technological development fund large amounts of energy research. Likewise, its Intelligent Energy Executive Agency is spending $730 million between 2007 and 2013 in support of research into energy saving, energy efficiency, renewable energies and the energy-related aspects of transport in the EU, Croatia, Liechtenstein, Iceland and Norway.

• In early 2007, the first East Asian Summit resulted in the creation of the Energy Security Accord — a program designed to reduce Asia's dependence on fossil fuels and promote the use of alternative energy sources. During the second EAS, which met recently with 16 nations participating, Japan promised $2 billion in aid to Asian countries to help improve energy efficiency and to adopt clean technologies that would reduce greenhouse gases.

• Energy management and efficiency efforts are also under way in Australia via the Victorian Parliament passed legislation, which provides for a statewide rollout of AMI. Utilities operating in Victoria must begin rollout of AMI by Dec. 31, 2008 and complete installation in four years.

Making energy efficiency a reality

Help in ensuring that ZigBee delivers on the goals being set forth by policymakers worldwide is now coming from ZigBee Alliance members. They are using the full weight of their various offerings and expertise to respond quickly to changing energy policies. These efforts are actively demonstrated by a range of ongoing AMI smart meter pilot programs now being conducted by utility companies like CenterPoint Energy, Southern California Edison (SCE) and Sempra Energy, which does business as San Diego Gas & Electric Company. (SDG&E).

SCE, for example, is piloting its next-generation of electric meters program. Scheduled for rollout in 2008, it will improve customer service and enable customers to proactively manage their energy use. According to SCE, advanced metering has the potential to reduce peak power consumption among its customers by as much as 1,000 megawatts — an amount equivalent to the entire output of a major power plant. SCE also has an AMI program in place that will replace today's electric meters with “next-generation” electronic meter technology, thereby providing customers with time-differentiated rates and demand response options. Advanced meters can reduce day-to-day utility operational costs by streamlining processes and automating the matching of resources with energy demand. The scope of SCE's metering solution is to replace approximately five million electric meters for SCE's residential, commercial and industrial customers (below 200 kW in demand). Note that while SCE is an electric utility, it fully expects that other gas and water utilities in its area will be able to leverage its AMI by communicating data from water and gas meters through the use of a ZigBee HAN.

SCE neighbor, SDG&E cites the use of ZigBee technology as one of the 13 initiatives outlined in the “San Diego Smart Grid” study authored by its energy consultants. This study builds a business case for AMI and offers a benefit analysis to increase the number of customer-owned distributed generation systems, like residential solar systems. SDG&E's AMI initiative institutes a supervisory control and data acquisition (SCADA) switch rollout program, seeks new energy supply from energy efficiency, demand response, renewable energy and distributed generation, and more. Implementation of the AMI initiative, along with the 12 others spelled out in the report, could generate $1.4 billion in utility system benefits and nearly $1.4 billion in societal benefits over 20 years.

Another ZigBee Alliance member, CenterPoint Energy, is rolling out AMI technology across its territory in Houston, Texas where it services more than three million customers. Its use of metering technology from ZigBee promoter Itron gives CenterPoint a ZigBee connection point to every customer. In the future, this new technology is expected to give customers the ability to better manage their energy usage using real-time price signals and the ability to remotely control appliances to reduce consumption.

The bottom line

ZigBee's wireless open standard technology is today being selected around the world as the energy management and efficiency technology of choice. Policymakers are including it as a key component in their vision for improved energy management and efficiency, and utility companies are helping to realize those visions in a range of ongoing pilot programs. It is playing a major role in how energy is priced and used. Consequently, consumers and businesses will soon see changes they never imagined possible. As members of a global society, that means that each of us will now have a larger opportunity than ever before to play an increasingly important role in improving the planet's environment and shaping a new future for generations to come. The “tipping point” is indeed here and much bigger than ever imagined.

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Bob Heile is the chairman of the ZigBee Alliance. He is a 20-plus-year veteran in the field of data communications and wireless data with several articles and workshops to his credit. He is also a founding member and chair of 802.15, the IEEE working group on wireless personal-area networks, chairman of the ZigBee Alliance, and chair of 802.15 Task Group 3a looking at UWB and other PHY layer alternatives for 802.15.3.

Utility customers' use of ZigBee-enabled products allows them the ability to:

• View and react to energy consumption by the minute, hour or day.
• Track pricing and adjust energy usage to conserve energy during peak demands.
• Plan, budget and pre-pay utility bills.
• Save money during price fluctuations by reducing energy consumption.
• Enjoy discounts on energy management programs.
• Help the environment by reducing their carbon footprint.
• Adjust and control their environment and enjoy “in-time” comfort.

Utility companies can exceed customer-service expectations and enhance operations by implementing AMI and ZigBee HANs to:

• Improve resource management and efficiency.
• Manage peak load.
• Increase revenue assurance.
• Improve meter-reading efficiencies.
• Optimize field workforce productivity.
• Detect and verify outages.
• Manage large volumes of meter data.
• Manage energy use at multiple facilities.
• Improve distribution reliability and efficiencies.
• Establish vital data source for optimizing energy and water delivery.

ZigBee-based Smart Meter in action

Control4 recently launched a demonstration event showing a smart-metering system in action. Designed to educate others, the demonstration highlights a fully integrated smart-metering system that uses a Cellnet Focus AX-SD utility meter outside of the house. This meter integrates a ZigBee-enabled transceiver. Messages sent by the energy utility are received by the meter and sent via a ZigBee radio to the Control4 ZigBee-enabled home theater controller (HTC). Control4's HTC then communicates to other ZigBee-enabled devices such as a wireless thermostat or wireless in-wall and outlet-based lighting control devices. All of these technologies work together, enabling consumers to wirelessly control energy consumption.

The demonstration system has three predefined electricity rate messages: low, medium and high. It demonstrates the type of messages a utility might send to communicate an immediate change in electricity rates. For example:

• Low rate periods allow for normal modes of heating, air conditioning and lighting.

• Medium-rate periods see the utility sending a message through the meter to the HTC alerting the customer of a rate change. The HTC could then be programmed to change the thermostat and/or change the lighting levels. The message could be announced visually and audibly through a TV set, for example.

• High rate periods or emergencies allow the utility to request the system take more aggressive action such as turning off the heating/cooling, lights and other non-essential devices. After the emergency has passed, the low or medium-rate period would automatically restore use.

In the demonstration system, energy use and current rate mode are indicated by the Control4 system's on-screen and touch-panel interfaces. The consumer can choose the lifestyle response (e.g., lights or temperature) to the various utility rate changes through this interface. Set points can also be determined through agreements with utility companies or based on price fluctuations. This approach gives consumers the ability to decide how much energy to consume, when and at what price. It is a prime example of ZigBee in action.