Moving beyond AMR
In the USA alone, the number of meters with AMR has risen from 3.2 million in 1993 to an estimated 11.8 million in 1997. Most of the companies have installed AMR systems to reduce meter reading costs, missed readings, and estimated reads.
However, in the rapidly changing utility marketplace, many utilities are looking for solutions that will improve overall operating efficiencies beyond their metering department; allow them to provide customers with better service and more choice; and provide ways of differentiating their product in markets that are opening up to competition.
Wireless fixed networks represent only a small percentage of AMR installations today, but they represent a fundamental paradigm shift in how utilities think about metering and information. A wireless fixed network offers real-time information on energy usage and status of the distribution system, which has value far beyond simply automating the meter reading function (see Table 1).
In addition to these benefits, a utility can also enhance its ability to attract and retain customers in competitive markets by developing a differentiated brand. It can do this by offering more pricing options, more customer choice, more products (utility and non-utility), and better customer service. The utility can also obtain new sources of revenue.
In a disaggregated utility environment, the utility can generate profits through:
- the improved ability to purchase and trade electricity, due to the availability of accurate, real-time usage information
- the ability to offer time-of-use rates, for which the utility may charge a premium
- the ability to shed load (through innovative rate structures) and bid it into the pool as a resource
- the ability to select contestable customers based on their actual consumption patterns.
The utility can participate in and benefit from the range of non-utility services that can run over the BCN network. The network is ideally suited to provide low-cost data communications with fixed end-points. Non-utility applications being developed to run over the network include
- home security
- vending and office machine monitoring
- streetlight monitoring.
The BCN network, which is similar in architecture to other network providers, consists of three levels:
- the Local Area Network (LAN)
- the Wide Area Network (WAN), and
- the System Controller Network.
The BCN network is made up of thousands of LAN "microcells," each consisting of hundreds of endpoint devices (e.g. meters) and a MicroCell Controller (MCC). The MCC lies at the centre of the microcell, and can process information from up to 750 endpoint devices.
To keep the overall costs of the network low, BCN houses most of the intelligence in the MCC and relies on an inexpensive endpoint radio for electricity, gas or water metering. In most cases the endpoint radio is one-way; it transmits detailed interval information to the MCC irrespective of the customer's tariff.
The meter also transmits tamper, outage, and power restoration information. The MCC gathers the information from each meter and processes it according to the customer's tariff. Metering information is transmitted up from the MCC via the WAN to the System Controller on a daily basis. Any alarm events transmitted by meters to the MCC (e.g. power outage alarms) are transmitted immediately.
BCN uses a WAN to transport data from MCCs and other devices up to the System Controller Network. In some markets, BCN builds out its own WAN, while in others it uses an existing public data network. While most of the metering information processed by the MCC is transmitted over the WAN at night, the WAN is used constantly to carry two-way diagnostic information and any alarm events (outages, for example).
The System Controller manages overall wireless and network communications and serves as the primary information access point for utilities. It consists of a network of workstations and file servers, and houses the network operating system (NOS).
The System Controller collects data from the wireless system and loads it into an Oracle relational database. Utilities access information via application gateways through ready-to-use formats. Two basic methods are supported - regularly scheduled batch file transfers and interactive real-time queries. A firewall between the System Controller and the utility network ensures secure data transfer.
WHERE DOES THIS TECHNOLOGY FIT?
Wireless NMR is not the answer for all scenarios. If the only driving factor for a utility is to reduce the direct costs of meter reading, mobile radio is likely to be cheaper and easier to implement. However, the technology is of substantial value in certain markets. These include:
- Countries with progressive regulatory climates favouring increased efficiency, customer service and competitive access.
- Countries facing high rates of energy loss or theft.
- Markets with constrained generation resources that need methods of reducing peak energy usage.
In these and other regions where utilities are interested in harnessing the power of real-time information, NMR can prove to be a powerful tool to achieve greater customer service, lower operating costs, higher system efficiencies and a truly competitive, open energy market.