Integration and Development of Enterprise Systems Using a Phased Approach
Michael Bernovich
PE, Project Manager
Pacific Gas & Electric Company
San Francisco, CA
History of Legacy Systems
Over the last twenty years, PG&E, like many large utilities have traditionally used a
combination of legacy engineering/work-order-generation, work management, materials
management, CIS, and financial systems that were implemented on a disparate range of
software and hardware platforms from mainframes, mid-tier client/server architecture,
and PC clients. Some of these systems were implemented at a near enterprise scale, such
as the financial and CIS systems. Others, such as the engineering/work-order system
were issued at the business-unit level as a generic standard system, but the local offices
had the ability to customize and tailor the application to various degrees; this was
especially true as segments of the engineering/work-order functionality were pared away
from the former PC MSDOS based system and were migrated to PC Windows version,
some of which had a client relationship to the mainframe portion of the application. There
were also a few purpose built work-management systems instituted at a
Divisional/Departmental level, but there was no "standard" across the utility or enterprise
until the newly implemented SAP based system was rolled out recently.
Since these systems have been developed and implemented through the years as computer
technology evolved, it was extremely difficult and costly to integrate these legacy systems
in order to collate, extract and leverage the valuable information needed for asset and
enterprise management. Especially where some of the applications and systems were
built entirely in-house, some were externally developed systems that evolved virtually
into in-house system, and others that were based on off-the-shelf or purpose built
externally developed software; a whole range of development archetypes.
In more recent years, PG&E's corporate IT strategy was to move towards an enterprise
management system that either included the functionality, meaning that the existing
business processes and methods would be adopted wherever possible, or interfaces, be
they either technologic or process-based, would be developed to integrate the
aforementioned legacy systems with the new enterprise solution. The selection and
implementation of the SAP financial, material and work management systems sets the
stage and, a starting point, for work process re-engineering and legacy system integration.
With the Utility Industry currently undergoing Electric Restructuring, expanding on
existing gas deregulation and market expansion, PG&E must reduce spending everywhere
to remain competitive. Since limited budgeting is available each year for work process reengineering
and enterprise systems integration, PG&E had to identify and prioritize the
work processes and systems that need to be integrated with the enterprise management
system and provide the maximum cost benefit.
This resulted in a priority based, business-drivers-as-primacy process being used to
determine what legacy functionality would be used in the enterprise system, dictating
business process changes, or, what legacy systems would be integrated with the enterprise
system. The basic equations were:
"Legacy functionality can be obtained in enterprise system = Retire legacy
system"
and
"Legacy functionality could not be obtained in enterprise system = Retain
legacy system and interface".
Of course, there were some gray areas, where the legacy system was retained, but only
allowed to integrate "manually", meaning that data was transferred via paper/keyboard.
