The New Han Dynasty

Compos Mentis

The actual Han Dynasty spanned the period of roughly 200 BC to AD 200. Wikipedia tells us that, “The reign of the Han Dynasty, lasting over 400 years, is commonly considered within China to be one of the greatest periods in the history of China.”

Today, however, there is a new HAN Dynasty – the Home Area Network (HAN). Originally, the roots of HAN began in California but are slowly spreading its influences throughout North America. Will this be one of the greatest periods in the history of Advanced Metering Infrastructure (AMI)? Perhaps; the jury is still out.

The progenitor of the new HAN Dynasty is Southern California Edison (SCE), a large and proudly innovative electric utility. The other two large investor-owned utilities in California, Pacific Gas & Electric Company and San Diego Gas & Electric Company are now retrofitting their original AMI plans to also include an AMI HAN interface.

Over the years, SCE has envisioned a number of communications and control applications and products that exist on the customer side of the meter. In some cases, SCE claimed a proprietary interest in these applications. Some vendors recall the stillborn concept – ‘Demand Subscription Service’ – of the late 1970s and early ‘80s, or later concepts – ‘House of the Future’. Other utilities have similarly tinkered with various quasi-home automation or home ‘gateway’ aspects of energy management. Most have failed.

Over the last two years SCE has faced the imminent procurement of a large AMI system. As a result of that process, SCE has assumed a position of leadership in specifying the HAN communications interface to be embedded in the communicating meter. SCE’s neighbouring utilities to the north and south now face the same challenge. It is a huge commitment. There is the need to understand why, how and when the consumer will use those communications. It is all fresh ground. The presumption is that market forces will prevail, and enlightened customers will purchase compatible standards-based display and control technology devices from various retailers. Another presumption, those enlightened customers will ‘see the light’ and have the tools, information and technology to control that ‘light’ during off peak periods. Also a presumption, these enlightened customers will react to save themselves money, save the planet, or both.

The Electric Smart House was a highly visible demonstration of home energy automation, with sponsorship by the Edison Electric Institute, the Electric Power Research Institute, National Rural Electric Cooperative Association and many prominent suppliers. It demonstrated many things – complex rates, displays of costs of various loads, automatic customer-selected choices in response to TOU and dynamic rates. But perhaps the most important conclusion was that technology is not the problem! That was 1994. This is now.

If technology is not the problem, what are the real problems? Where are the challenges? If the application is clear (the requirements for a customer display device, load control device, etc.), is the devil in the details? Yes. Shall we communicate with RF or PLC? What’s its range? Is it a standard? How stable is the standard? What’s its cost? Should there be a statewide standard? Or should each utility go its own way?

Perhaps the most frustrating aspect of all to the entire community is that until a HAN interface is firmly specified, and until purchases are made, no large installations can take place. Vendors need ramp-up time to start building and delivering the huge quantities of HAN-ready AMI meters needed by these utilities. It is unfortunate that many of the issues that now haunt these decisions perhaps should have been resolved a year or two ago. HAN could be the path of progress in demand response, and should not be a log in the path for delay.

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