December 2008

Cover Story

Power plant wireless economics 101

Evolving wireless landscape key in solution design; future proofing, flexibility to migrate remain top considerations

Fast Forward

  • Wireless providers strive to create their own proprietary niche.
  • NERC Cyber Security standards make wireless security a regulatory issue.
  • On a point per point comparison of wired vs. wireless, an 80% savings realized.
  • Monitor more equipment, more often, reducing damage, failure, and shutdowns.
 
By David Runkle

Deploying wireless applications has typically occurred in an ad hoc fashion with a point-to-point solution used to solve a specific issue without any real long-term strategic plan.

Without a roadmap, what will allow these islands to coexist? Allow for scalability? Allow for system management for security purposes to satisfy IT requirements?

What prevents these systems from interfering with each other as the number of installed applications grow and use a number of differing wireless protocols and standards?

With the return on investment (ROI) being a key driver, a user needs to look at the actual economic savings using a simple wired versus wireless comparison. There is one example of a proven installation of many applications within one common infrastructure to create an umbrella of redundant wireless coverage over the entire facility.

With this umbrella installation, the user can focus on the widget that solves the business problem, allowing users to focus on the issues of interoperability and compatibility with other wireless systems. This can all happen in a manner that forms a strategic roadmap to "future proof" the entire site for its useful life.

This is what happened at the Lost Pines Power Park, a Lower Colorado River Authority (LCRA) facility in Texas. It has two unique facilities-an aging, conventional, natural gas fired power facility (Sam Gideon Power Plant) and a new combined cycle facility (Lost Pines 1 Power Project).

Strategic wireless roadmap

Being an early adopter of wireless technologies throughout a facility-wide system, it became obvious there were many factors and dynamics that needed dissection to reap the benefits of the elimination of copper conductors. We did this while satisfying all stakeholders of the organization and remaining compliant with emerging regulatory requirements from North American Electric Reliability Council (NERC) standards.

The environment at LCRA during the conceptual stages of this project involved risks. There were quite a few people that did not really understanding the differences in wireless protocols and their own strengths and weaknesses.To add to the complexity, individual wireless providers strive to create their own proprietary niche limiting the consumer's ability to select the application that best fits their needs to solve unique issues.

Wireless security, especially when interfacing with the plant's distributed control system (DCS) has become a regulatory issue since the onset of NERC Cyber Security standards. This technology also forces a convergence of the process control professional with the information technology professional in an area that heretofore has had distinct boundaries.

Since a wireless infrastructure usually requires an interface between the corporate local area network and the DCS network, system security and data protection becomes critical, as does the coordination of a peaceful coexistence of these two worlds.

Finally, the requirement for the management of the wireless network for maintenance, intrusion detection, software and firmware upgrades, real-time system health reporting, and competent technical expertise in this technology becomes critical to the success of a new technological installation.

In a new and leading edge technology, the expertise level of existing staff may be insufficient due to lack of experience.

During the decision-making process of the LCRA installation, wireless standards were rapidly evolving, and it was anyone's guess which one would prevail. At the time, the development of industrial wireless standards was still in the early stages with groups like ISA100 and the HART Foundation soliciting technical papers and proposals.

Furthermore, the existing use of wireless was largely the business office use of Wi-Fi and the serial radio communications used in Supervisory Control and Data Acquisition systems.

Newer wireless technologies like ZigBee and Ultra-wide Band were part of the wave of wireless sensor networking initiatives. Companies were just starting to understand the "network effect" that wireless offered if used in a systematic and engineered manner.

The evolving wireless landscape was a key factor in designing the solution. The technologies and products chosen today would inevitably be better, and it was important LCRA had the flexibility to migrate to the newer products once they became available without having to replace the initial system.

This notion of "future proofing" was a core consideration in moving forward as an early adopter.

Addressing each of these risks through the selection of the wireless solution was critical to the long-term economic return on the initial capital investment made.

Vendor neutrality was a very attractive attribute and offered a method for mitigating all the risks that existed at that time and, in a large part, today.

Business case analysis

Driven by the need to allow for communication of the two newly integrated staffs, the lack of a unified infrastructure other than the phone system presented serious challenges to increase productivity and personnel coordination. The low hanging fruits were obvious but expensive in the traditional ways. Then there were added risks of significant excavation requirements in an older industrial site that lacked accurate documentation of systems added over its 42-year-old existence. All along, the driving catalyst being obsolete GAI-Tronics public address system and the other plant (LP1) having none.

Budgets for the following year's projects took place in the usual manner, estimating replacement costs based on a budgetary request with formal Request for Proposals (RFPs) following as these budgets gained approval. Upon receiving the responses to these RFPs, the lack of accurate, up-to-date drawings proved to be a problem for estimates being grossly inaccurate.

Having been a Strategic Alliance partner with Invensys/Foxboro for over 17 years, annual alliance meetings took place for strategic planning initiatives. Coincidently, literally two weeks after learning of the underestimation of the communications integration project, Invensys introduced LCRA to Apprion. Apprion is a vendor-neutral industrial wireless provider that could deliver a solution.

A purchase order for a wireless site assessment resulted from the annual meeting. That solution would replace the obsolete GAI-Tronics system at the Sim Gideon Power Plant. Also included were the addition of a new public address (PA) system at the Lost Pines site and providing the ability for facility wide broadcasting capabilities in the event of an emergency for increased personnel safety. This would occur through integration with the PBX and the addition of wireless broadcast loudspeakers.

Working through the business case analysis utilizing sound Project Management principles of project planning and costing, staff considered three options. Do nothing, a wired retrofit of the GAI-Tronics system and addition of an original system for LP1, or a complete wireless solution to solve the business need. Staff performed cost analysis on each option.

The do nothing solution quickly proved not viable due to the costs associated with maintaining an obsolete system and efficiency losses stemming from the lack of effective communication of a staff that were now working from a common maintenance backlog at either plant.

A comparison developed with variables of material cost, installation costs and downtime required, engineering-time cost comparisons, drafting costs, administrative costs required of a project of this magnitude, and general overhead. Wireless had the clear advantage in all areas.

The results of the comparison were sobering. The initial capital investment to replace the PA system with a voice over Internet protocol (VoIP) system complete with a wireless infrastructure that provided an "umbrella" of wireless coverage over the entire facility was justified. It showed the wireless solution to be a 40% lower cost than the wired option with an initial savings of $400,808-these savings coming from reductions in costs in all the variables used in the comparison.

Continued system additions

Along with the savings realized on the initial replacement of the communications VoIP system, the facility now had a wireless infrastructure that we could use for all additional installed applications at an incremental cost on a per point basis. This was the most intriguing aspect of the installation of an open, vendor neutral, managed infrastructure.

The possibility of continuing to reap benefits in costs savings and increased efficiencies were promising but very difficult to quantify because data did not exist for accurate comparables at that time.

Almost two years later, LCRA continued to add diversified applications to the existing wireless umbrella already implemented. We added wireless sensors from Emerson. The company's wireless sensor products worked well for the facility already standardized on Rosemount and Fisher field devices.

Specifically, DP transmitters brought in levels from a tank farm hundreds of yards from the plant site, utilizing WiMAX and the successful integration of the Emerson 1420 gateway with the ION system.

Two protocols were now working within one common infrastructure. We also added condition monitoring to rotating equipment using SwanTech's stress wave analyzers to provide real time equipment health data to the control room for increased response time to equipment malfunction.

We added wireless contacts and sensors to plant equipment to take advantage of already existing but stranded diagnostic information. The new applications also provided additional alarming functionality of less priority equipment that would have never have made it into the budget due to the high cost of hardwiring equipment out of the immediate plant boundaries.

The list of planned wireless applications continues to grow. However, growth often adds the potential of radio interference.

Using data from these additional wireless projects that also used the existing wireless umbrella we developed a wired vs. wireless calculator to provide a comparison of incremental and continued ROI between wireless and wired applications.

Variables used in this calculation included material price, installation labor by discipline at known rates for the area where the work was being performed, engineering costs, drafting costs, and general administrative and overhead.

We did a cost analysis using actual data from LCRA's financial and work management systems with values derived from actual data for the variables used in the calculator. We calculated an average cost of each point added to the wireless network on an incremental basis that leveraged the wireless infrastructure already in place. On a point per point comparison of wired vs. wireless, LCRA was able to realize an 80% savings per point added to the wireless network.

Using this information and based on the savings of $400,808 on the initial capital investment of the PA replacement, we showed 58 additional points added to the wireless network at a savings of 80% per point would provide additional savings of $192,400.

Taking the sum of these two numbers equals the entire cost of the initial project to replace the GAI-Tronics system at the Sim Gideon Plant and to add a new PA system at the Lost Pines Plant of $600,912-plus, 58 additional points.

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Benefits not quantified

Aside from the direct economic cost comparisons of a wired vs. wireless network, other benefits will be realized as the system grows and more points are monitored and additional applications added.

This will provide additional maintenance and operational enhancement for increased productivity. Increasing productivity of personnel allows free time for other tasks as local data for vibration, temperature, pressures, and levels incorporate with the DCS system in real time.

Instruments can be calibrated without the need to send personnel into the field; equipment diagnosis can be performed remotely and improve the mobility of staff to multi-task armed with more information in the field.

Operational benefits improve as data collection on equipment is better. Before, we would not have added some monitoring devices because the traditional hard wiring would have been excessively expensive. Now, we monitor more equipment more often, which reduces equipment damage, equipment failure, and forced system shutdowns. All of these collectively will improve reliability by reducing expensive unit outages.

This translates into labor hours saved ($), reduced personnel required ($$), and reliability improvements by reducing unplanned outages ($$$). Wireless points and applications can usually get on board faster, cheaper, and without outages for installation requirements needed for wired installations.

Regulatory requirements can be satisfied faster and safety of personnel improved.

Wireless is a proven technology ready for primetime and promises to be the next paradigm shift in technological systems having a major influence on the entire industry not seen since the transition from analog to digital technologies.

ABOUT THE AUTHOR

David Runkle (drunkle1@mac.com) was the recipient of the 2007 ISA/EPRI POWID facility of the year award for bringing innovation to an aging power facility. He has degrees in business, electronic technology, and financial planning and is the former production manager for LCRA Sim Gideon Power Plant and the Lost Pines Power Plants. He works at ROI Consulting.

TERMINOLOGY

Combined cycle is characteristic of a power producing engine or plant that employs more than one thermodynamic cycle. Heat engines are only able to use a portion of the energy their fuel generates (usually less than 50%). The remaining heat from combustion is usually wasted, but not so in a combined cycle. In a combined cycle power plant, the waste heat goes to further use to make steam to generate additional electricity with a steam turbine, which of course enhances the efficiency of the entire operation.

GAI-Tronics refers to communications solutions for challenging and or expansive venues including mass notification, paging, intercom, general alarm, public address, process communications, emergency notification, and as in this article power plants and industrial areas. It is the name of a company that has become synonymous with the product (www.gai-tronics.com).

 

RESOURCES