PG&E Automates Pole Inventory System Pen-based computers and customized software manage database of 2.5 million wood distribution poles.

Pacific Gas & Electric Co. (PG&E), San Francisco, California, U.S., has taken its computer system into the field. The field automation project is driven by the need to reduce operating costs and improve customer service. Its first application: to collect detailed information on the wood poles in PG&E's distribution system.

Using pen-based field computers and customized software from PenMetrics Inc., Corvallis, Oregon, U.S., PG&E is developing a sophisticated and complete database of its distribution poles. To carry that even further, PG&E has undertaken its test and treat program, which will test the condition of every pole and then apply chemicals to prevent decay from fungus and insects.

With more than 87,000 miles (140,000 km) of overhead electric lines strung along 2.5 million wood poles, the distribution system represents an essential part of PG&E's infrastructure assets and a substantial capital investment. PG&E estimates the field programs will give the utility a net savings of more than US$280 million in pole repairs and replacements over the next 30 years.

Field Automation Pioneer PG&E is the largest investor-owned utility in the United States. It serves 4.4 million electric customers in a 73 sq mile (189 sq km) region of northern California, from Bakersfield to the Oregon border.

PG&E is a pioneer in field automation, implementing its pilot applications in 1994. Its field automation program is led by Jim Sprecher, principal electric engineer in the Electric Distribution Dependability Department_a name aptly chosen to reflect the utility's growing emphasis on reliability and customer service. Working closely with the Computer Technical Services Department, Sprecher has taken the lead in PG&E's field automation implementation, championing the user viewpoint.

Currently, PG&E is focusing only on its distribution poles with a two-part field data project. First, PG&E will conduct an exhaustive, detailed inventory of its 2.5 million wood distribution poles. PG&E calls the second part of this project its "test and treat" program. Field crews assess the current condition of poles and then repair or apply chemical treatments that will prevent future damage, most commonly from insects or fungus. For much of its operating area, the inventory and test and treat programs will be conducted simultaneously, enabling the company to achieve even greater cost savings.

Pragmatic Implementation Like most utilities, PG&E increasingly relies on digital databases to keep track of its field assets and to chronicle maintenance, changes, additions and improvements in its distribution system. But PG&E has taken a radically different approach to implementing that technology.

Unlike most utilities, Sprecher's department decided not to start with a geographic information system (GIS), but to focus first on the data itself. In GIS, 60-80% of the project's costs are related to data collection and validation. PG&E put its emphasis on collecting data that would help achieve some of its most pressing operational goals.

The utility selected this contrastable approach even though its land department already operated a GIS, which is used primarily for transmission lines and feed property.

"We talked to them about integrating. The compatibility was there but not the need," Sprecher said. With 2.5 million poles, as well as other associated structures, the cost was just too high. "We decided to wait until technology catches up and it becomes more economical," he said.

Instead, Sprecher said, PG&E developed an initial land base that contained only the most essential geo-referencing—street names, centerlines, key geographic features—just enough to enable field crews to identify the locations of specific structures. To develop this graphical land system, PG&E scanned manually drawn maps to create a series of TIFF (tagged image file format) raster images, files that could be used in conjunction with the PenMetrics FieldNotesr program. The corners of each map were then geo-referenced using the California State Grid System. With an accuracy level of plus or minus 10 ft on a scale of 1 inch=100 ft, the system was rudimentary by today's GIS standards. Still, it was sufficient to begin developing an accurate and usable pole assets database.

In the future—when costs and budgets allow—Sprecher's group will integrate its system into the corporate GIS, complete with geographic positioning system accuracy and real-time updates. In the meantime, the department has a functioning system that puts the computing power where it can improve operations the most.

Focus on Field Efficiency PG&E's system is designed with field efficiency in mind. The system is simple, convenient and easy to use. Map images for an area are stored on small, reliable PCM/CIA cards. The computers themselves use flash memory hard drives, to which field data are recorded. With no moving parts, the flash drives are extremely durable, ideally suited for field applications.

With the map data loaded onto their pen computers (Fig. 1), field crews visit each pole, log its location and enter the essential characteristics that must be attained in the field. These attributes include location; type; other structures attached to the pole, such as power lines or transformers; and foreign attachments, such as cables owned by the phone or cable TV company (Fig. 2).

To place a pole or other structure on the map, the operator touches the screen with the stylus. The software automatically assigns the x, y coordinates based on the registered corners of the map. Then a data-entry screen opens and the operator enters the data relevant to the object. At the end of the shift, the PCM/CIA cards are collected and the data is uploaded to the master database. With this approach, PG&E is building its electronic facilities database first hand as it reviews the facilities in the field.

This approach sharply contrasts the traditional method. Before the advent of field automation systems, crews were sent out with paper copies of the latest facility maps. As they moved through an area they made notes on large, awkward maps and wrote out attribute information on paper forms.

The maps and forms were then collected and given to a crew of data-entry operators who manually copied the information into the system. A separate team of operators made drafting changes to the digital maps, and then the two merged and checked for quality through a series of batch process applications. The process relied on the ability of the field crew to communicate its findings accurately to the data-entry staff. However, if a question arose, there was no easy way to get clarification. The data-entry operator often just guessed to keep the process moving.

This approach was time consuming, costly and error prone, but until recently it had been the only option. Using a field automation approach, PG&E has reduced the process from dozens of steps to a single step. The data are entered in the field while operators look at the structures. If operators have questions, they do not have to guess or send another operator out to the field to clarify a discrepancy. Rules are embedded in data-entry forms to help guide the field operator and eliminate the most probable errors. Work time can be reduced from weeks or months to a day or less.

A crew's data can be uploaded to the system at the end of each day. More importantly, the cost of data collection and validation can be substantially reduced with a higher degree of confidence in the data. Data confidence directly correlates to the value and acceptance of the system.

Enterprise-Wide Implementation PG&E is extending its commitment to field automation. In the next several months, Sprecher expects Field-Notes to be deployed in all 18 of the company's divisions. Within the next three years, the utility will introduce applications for its other distribution networks, including other overhead structures and underground and infrared facilities, as well as its gas operations. PG&E will also implement applications for vegetation management and tree-trimming.

Spatially referenced inventories are essential for PG&E's plans to build a complete and robust facilities information management system. These field automation applications represent the first steps of PG&E's Technical & Applications Support Group, which is building the system to incorporate essential outside plan data with a robust grid coordinate reference system.

Sprecher explained the project is driven by the need to improve accuracy and efficiency in two key areas:

- Customer Billing. Identifying the operating and maintenance costs associated with each specific address will allow PG&E to accurately charge individual customers, which will ensure that customers are paying for all the energy they use and that a large user is not pay-ing too much for its energy, leaving an opening for raiding utilities to "cherry pick" PG&E's best customers.

PG&E's current billing practice is based on an average of aggregate costs—a rate structure that aggregates the capital asset value of both newly installed and appreciated assets with other operating costs. The impact of newly installed capital assets is equitably shared by all customers.

- Spatial Analysis. A geographic-based system must be able to provide detailed attribution information on circuit devices, in addition to mapping location, to accurately portray electrical circuit modeling. PG&E's current GIS does not have the abilities the utility needs in this area but, as Sprecher points out, "First thing's first."

Before any analyses can be performed, you have to have the database. Sprecher said PG&E's approach rightly puts the horse before the cart. Many utilities have implemented GIS software only to find it is obsolete years before they can get enough data input to make the system functional enough to demonstrate a reasonable return on investment.

Sprecher is determined not to follow that course.

"Technology is changing every day, but sound data remains constant," Sprecher said. "In a few years, this technology will probably look substantially different and cost significantly less than today's systems. When we're ready, we will move right into the state-of-the-art capabilities."

Moreover, Sprecher makes a compelling argument for PG&E's approach. With only two of seven applications completed and annual savings exceeding US$50 million, field automation has positively affected PG&E's balance sheet. As the system grows, Sprecher is confident those savings will also grow.

In the race to optimize for competition, PG&E is positioning to maintain its lead.

Acknowledgment: The author would like to thank Jim Sprecher, PG&E, for his assistance in preparation of this article.

With electricity rates likely to drop sharply as competition increases, utilities are working now to reduce operating costs at every turn. Any innovation with the potential to reduce costs, increase efficiencies, maintain and improve safety and enhance customer service will be reviewed carefully and, if it works, embraced by the industry.

Consider, for example, the potential productivity gains if engineers and maintenance workers had access to current, accurate, geographic-referenced information in the field. Many utilities believe substantial increases in efficiency, first from direct cost savings in data collection and validation, and ultimately from more effective deployment and maintenance of outside plant assets can be realized through field automation initiatives.

The need to reduce data collection costs in the field has led to a resurgence in interest in pen-based computing, which had fallen on hard times in the last few years. It had its early hey day in 1990-91 after pen computers caught the attention of high-tech venture capitalists. But a few high-profile failures, most notably Momenta and Go Computing, reversed the industry's public fortunes. Like so many other promising technologies, Wall Street's hot interest turned ice cold. The technology really hadn't matured and investors, expecting a fast and high-percentage return on their investments, were disappointed.

However, the pen is a natural way to interact with a computing device and has distinct advantages over a keyboard or mouse, particularly in settings where you don't have a horizontal surface to work on or you need to use your hands.

Pen computing owes much of its resurgence to recent advances in the computers themselves. Practical pen-based applications for utilities require substantial processing power, memory and storage capacity in a portable, durable box suitable for field use. With hardware prices declining and functionality increasing enough to adequately support field applications, the pendulum is swinging back and utilities are showing increased interest in the technology.

J.D. Wilson is a freelance journalist in Aurora, Colorado. He specializes in technology in business, especially related to utilities.

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