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Thank you for inviting me to participate in this meeting on geographically distributed systems.  I have been practicing professional engineering for nearly 30 years, of which more than 20 years has been involved with earthquake engineering.  Many of you are responsible for the research that I, as a practicing earthquake engineer, have had the opportunity to use to develop solutions which have improved electric utility earthquake performance.
I am going to talk to you about the electric utilities perspective of what a Power System is with respect to earthquake vulnerability, an idealized organizational decision making structure, and suggest several opportunities for earthquake engineering research with respect to seismic safety, loss reduction and increased system reliability.
So lets now look at the opportunities for improving the Seismic Performance of an Electric Utility system.
I am going to start with an actual event.  An earthquake strikes within an area that an electric utility has facilities located.
The clock is moving very fast at the beginning of this process, and that speed requires information about what was damaged, usually within a few seconds to a few minutes. 
Emergency response takes a little longer.  The first hour is called the golden hour, when emergency response may or may not be very strong.  But, starting at the end of that first hour, emergency response needs to be up and running until service is restored.
Repairs begin to start when enough resources have been gathered at the site of damaged facilities.  This generally takes about 4-6 hours to get started.  Repairs, as indicated here involves debris removal and demolition as well as fixing the power system, generally with materials that are already on hand.
Reconstruction is the process of rebuilding portions of the power system that could not be repaired.  This process often starts within the first 24 hours and can go on for weeks or even months after service is restored.
At some point, the emergency response efforts have repaired or reconstructed enough of a power system to restore service to all the customers that have lost power.  For many this is the end of an event, but not true for earthquake engineers.
Facility planning starts up after the emergency response phase has completed.  This effort takes months, and in some cases years to complete.  The opportunities for earthquake engineering that exist during this phase come from asking questions like what can be restored to gain the same redundancy and robustness in the system prior to the earthquake, and what needs to be upgraded to avoid damages of the type that just occurred. 
Mitigation becomes an annual event and is the first indication that an electric utility is beginning to return back to normal after an earthquake.  Mitigation generally starts within a year after an earthquake and can continue on until the next major earthquake disrupts the utility.
Communication that was extremely important right after the event, continues to be important is shaping individual actions and corporate policy long after an earthquake occurs.  As the lights all begin to come back on, many feel that it is now time to turn attentions to other problems facing the electric utility.  But, in fact, communications about the issues that earthquake engineers are involved with become extremely important, right after the lights are turned back on.  Expectations about earthquake performance become important in measuring an electric utility’s performance.  Law suits are settled through the process of communication in court.  Efforts to increase or decrease regulations of electric utilities require many hours of communication over long periods of time.  Politically active special interest groups require communications to foster understanding with the electric utility. 
System planning is an area that has received very more attention by earthquake engineers in the recent past.  Many opportunities to enhance electric utility performance during and after an earthquake are just beginning to be discovered.  Distributed area control systems, game theory algorithms to model emergency response and improved micro-economic impact modeling are just a few of the new opportunities that exist in system planning.
Lets talk in a little more detail about some of the opportunities that exist in this circle of time that follows an earthquake.
Seismic safety is a term that is often understood.  It is often assumed to mean those actions that are required to reduce the life threatening events.  It can have that meaning, but I prefer to use it in a broader context with respect to damage assessment, emergency response and emergency repairs.
Out in Mohave Desert the Landers earthquake broke and caused power distribution systems disruptions from Santa Barbara to San Diego along the West Coast.  Many electric utilities were aware that a major earthquake had just happened, but it wasn’t until customers started calling in to get their power turned back on that anyone knew the magnitude of that disruption.  Distribution power lines with slack spans between poles slapped together, faulted and burned down.  These disruptions were widely scattered and the impact on the utility was not realized for more than six hours.  The locations also did not follow any previously anticipated pattern, which further slowed the repairs process.  More rapid methods of collecting data, identifying damage and its location is an opportunity that exists throughout all electric utility facilities, but can be extremely helpful in the distribution system.
Currently, only very large customers are monitored remotely to determine what their power usage is at any particular time.  Opportunities exist to remotely sense customer service outages by circuits, customer types and areas, similar to the customer outage information that was being distributed through the internet during California’s rolling blackouts. 
Emergency management is one of those areas where very little has been done specifically for electric utilities.  We have instead relied on procedures which are revised after each event, and used in training operators and maintenance crews.  Opportunities exist to make the emergency response process more efficient by the incorporation of damage assessment data with information on available resources to develop task assignments and identify required resources automatically.
Opportunities also exist to enhance emergency response through the automatic selection of emergency response routes from the dispatch locations to the sites that have significant damages.  This requires the integration of information that is being generated by transportation organizations into the information being developed as part of the emergency management.
One of the major problems that faces the repair of electric utility facilities is the amount of time it takes to make repairs.  If the repair time follows closely after an earthquake main shock, potential exists to endanger repair crews working at a site from after shocks.  An opportunity exists to be able to optimize the kind of repairs that are being performed after an earthquake to reduce the risk of failure from aftershocks.
Soil structure interaction offers a significant opportunity for optimization of the repair process.  Liquefaction and landslide potential are not currently being evaluated for potential seismic safety concerns of crews doing repairs after an earthquake.
Emergency management often means developing a priority for a limited number of resources to make the power system as safe as possible in a short amount of time while restoring service to essential or critical customers first.  Many circuits that have downed wire after an earthquake represent a threat to the population because the wire is now on the ground.  If that circuit does not provide power to any essential or critical customers for emergency response, then those wires can be cut and cleared away to allow for repair at a later date.  Opportunities exist from damage assessment information in emergency management software to identify these potential seismic safety tasks and optimize the use of available crews.
Opportunities exist in the development of vulnerability models.  Currently these models examine the potential for damage at various levels of earthquake ground shaking.  They need to be extended both in depth and breadth.  More vulnerability models need to identify specific modes of failure for each component.  They also need to identify time and cost to repair that particular mode of failure for use in emergency management, which will help optimize the emergency response process.
Reconstruction is often about choices and alternative choices.  Emergency management software can identify alternatives that can be implemented during the reconstruction process that could reduce losses.  A work around that has been relied on in the past is the use of cotton rope to tie electric components together.  This alternative to complete replacement, did well until the first rain came along and the rope got wet, stretched and caused a fault. 
In developing more system reliability, facility planning often takes place without consulting earthquake engineers.  Opportunities exist prior to the next earthquake to identify what should be restored to pre-earthquake levels of seismic resistance and what needs to be replaced with updated seismic resistance.  Allowing this decision to be made by an insurance or FEMA claims representative is not the best approach to be make this decision.  I found decision made in the 1971 earthquake, often required additional expenditures that could have been avoided in the 1994 earthquake.
Opportunities exist to model the need for the maintenance of spare part inventories.  Technological solutions may not be readily available to avoid damage to certain components, but the ability to replace vulnerable components can greatly affect the amount of time required to restore service. 
Redundant systems have long been used by electric utilities to provide reliable power service.  An opportunity exists to consider earthquake hazards in developing redundant systems.
Current plans and specifications for equipment that is installed on site are often not available following an earthquake.  Opportunities exist to make this information available over wireless networks from centrally maintained data bases.
Access has often been a problem that delays the reconstruction efforts electric utility facilities.  Opportunities exist to identify and make changes in the accessibility of facilities after an earthquake.
Mitigation is the traditional role of the earthquake engineer.  Many advances in research have facilitated our mitigation efforts.  We have incorporated new materials such as fiberglass and rubber in place of porcelain for insulators.  We have further developed the use of passive energy adsorption systems.  We have modified codes and standards to do more full scale testing to qualify electrical equipment for seismic performance.
Opportunities exist to improve our understanding of which mitigation measures offer efficient solutions and which are not very cost effective.
We need better data bases of what performs well and what does not.
Current codes and standards need to be changed to include some of the new items such as base isolation of electrical equipment and soil structure interaction.
Upgrades or patches have been developed for equipment that need to be evaluated for performance and cost effectiveness.
Currently grants are developed based on cost effectiveness.  Opportunities exist to better determine if a mitigation measure is cost effective.
Opportunities to increase system reliability exist through research into communications.
If you cannot wave a magic wand to mitigate completely against the next major disaster, then we need to figure out how to communicate with others better.  Two opportunities for research include increasing awareness of the other stake holders and developing better tools to predict the potential for earthquake hazards and subsequent damage.
We need to be able to communicate more realistic expectations of electric utility performance, and develop a shared risk concept between electric utilities and other stake holders.
One of the seismic communities biggest set backs was the perception of a failure to predict a significant earthquake on a segment of the San Andreas fault at Parkfield in California in the late 1980s.  The memory of that perception often comes up, when mitigation measures are justified using probabilistic methods of hazard quantification. 
Opportunities in system planning are greater than in any of the previous categories that I have mentioned.  This area of concern is currently based on different disciplines that have different concerns.  An integrated approach to system planning is sorely lacking.
It should be possible to integrate the open circuit models currently being used by earthquake engineers with the dynamic load/generation balancing models used by electrical engineers for system planning.  Many of these models cover quite large areas.  An integrated model would be able to predict earthquake disruption of electric power flow and possible times of restoration of service outside the earthquake area. 
Economic models have been developed to describe the impact of electric power disruption on economic sectors within a region.  These models need to be enhanced into tools that can be related to customer types in an electric utility’s service area. 
Last, but not least is the memory of how our power grids have experienced cascading failures.  Recent experience of how difficult and time consuming it is to restore power using operators and centrally located control centers underscores the potential problem, when an earthquake occurs that destroys a significantly larger number of electric power facilities.  The technology of SCADA systems is advancing in a fashion similar to the decentralized computer network control systems.  If research can keep pace with technology, self healing power systems in areas that have undamaged facilities, could be broadly available over the next ten years.
So lets now look at the opportunities for improving the Seismic Performance of an Electric Utility system.
I am going to start with an actual event.  An earthquake strikes within an area that an electric utility has facilities located.
The clock is moving very fast at the beginning of this process, and that speed requires information about what was damaged, usually within a few seconds to a few minutes. 
Emergency response takes a little longer.  The first hour is called the golden hour, when emergency response may or may not be very strong.  But, starting at the end of that first hour, emergency response needs to be up and running until service is restored.
Repairs begin to start when enough resources have been gathered at the site of damaged facilities.  This generally takes about 4-6 hours to get started.  Repairs, as indicated here involves debris removal and demolition as well as fixing the power system, generally with materials that are already on hand.
Reconstruction is the process of rebuilding portions of the power system that could not be repaired.  This process often starts within the first 24 hours and can go on for weeks or even months after service is restored.
At some point, the emergency response efforts have repaired or reconstructed enough of a power system to restore service to all the customers that have lost power.  For many this is the end of an event, but not true for earthquake engineers.
Facility planning starts up after the emergency response phase has completed.  This effort takes months, and in some cases years to complete.  The opportunities for earthquake engineering that exist during this phase come from asking questions like what can be restored to gain the same redundancy and robustness in the system prior to the earthquake, and what needs to be upgraded to avoid damages of the type that just occurred. 
Mitigation becomes an annual event and is the first indication that an electric utility is beginning to return back to normal after an earthquake.  Mitigation generally starts within a year after an earthquake and can continue on until the next major earthquake disrupts the utility.
Communication that was extremely important right after the event, continues to be important is shaping individual actions and corporate policy long after an earthquake occurs.  As the lights all begin to come back on, many feel that it is now time to turn attentions to other problems facing the electric utility.  But, in fact, communications about the issues that earthquake engineers are involved with become extremely important, right after the lights are turned back on.  Expectations about earthquake performance become important in measuring an electric utility’s performance.  Law suits are settled through the process of communication in court.  Efforts to increase or decrease regulations of electric utilities require many hours of communication over long periods of time.  Politically active special interest groups require communications to foster understanding with the electric utility. 
System planning is an area that has received very more attention by earthquake engineers in the recent past.  Many opportunities to enhance electric utility performance during and after an earthquake are just beginning to be discovered.  Distributed area control systems, game theory algorithms to model emergency response and improved micro-economic impact modeling are just a few of the new opportunities that exist in system planning.
Lets talk in a little more detail about some of the opportunities that exist in this circle of time that follows an earthquake.