ELECTRIC UTILITIES ARE DEFINED BY THEIR ABILITY TO PROVIDE UNINTERRUPTED SERVICE to customers. However, in the case of severe weather, they are more remembered for how quickly they can restore power. As cooperative electric utilities, Community Electric Cooperative (CEC; Windsor, Virginia, U.S.) and Sumter Electric Cooperative Inc. (SECO Energy; Eustis, Florida, U.S.) have found that limited resources can slow the restoration process, so proper planning for potential outages must be a top priority.

WEATHER NEEDS

Most cooperatives cannot afford to have a trained meteorologist on staff; therefore, it can be more cost effective to invest in an industry-specialized weather provider. Most advanced weather providers are subscription-based services that supply more comprehensive information than the average daily or long-term forecasts. Ranging in services and cost — depending on the depth of information — advanced weather providers offer a variety of features, such as enhanced radar capabilities and real-time weather conditions for a specific service area.

Smaller cooperatives typically are not located in a large metro area, so the need for location-specific weather services is increasingly important. Unlike daily or long-term forecasts, advanced weather services provide frequent updates on current or developing weather conditions likely to impact the utility's ability to provide service to customers.

RURAL FORECASTING

CEC serves a rural coverage area with approximately 11,000 customers and is 45 miles (72 km) from the Atlantic Coast. As a result, the cooperative is vulnerable to a variety of unique weather conditions, all of which are capable of causing power outages and disrupting its daily operations. In any given year, CEC deals with weather-related outages caused by thunderstorms, tornadoes, hurricanes and the occasional ice storm.

CEC has chosen to invest in the same weather provider since 1992, using the MxVision WeatherSentry Utilities Edition from Telvent DTN (Minneapolis, Minnesota, U.S.). For operations and engineering functions, it is important to use a weather service customized to a utility's specific geographic area.

With this subscription service, real-time weather conditions can be viewed with customized radar and forecasts for the exact service area location. These features help the community cooperative more-accurately gauge weather information most likely to affect operations such as wind speed, precipitation, air temperature and jet-stream movement.

ACCURACY IS KEY

Windsor is a relatively small city; therefore, many of the local forecasts are generated out of nearby larger cities, which can be up to 30 miles (48 km) away from CEC's service area and are just not adequate. Having weather conditions as they relate to Windsor's exact location allows both a more-accurate path tracking of incoming severe weather and a better assessment of the impact on customers. In some instances, CEC can monitor a storm front's movements and narrow its potential impact down to a specific street. More specifically, the multilayered radar offers the ability to monitor multiple weather conditions for an area all from the same radar screen. Using these tools, CEC can easily add information variables to the screen, including precipitation, wind speeds, ground and air temperatures, and lightning strikes.

When severe weather is coming, CEC can see exactly when the storm will arrive, how long it will last and how it might impact the service area. The time-sensitive information is vital to the managers to ensure repair crews are not outside working on power lines when weather becomes more severe and to prepare for any outages that may occur.

When there is a possibility for severe weather, CEC staff receives customized weather alerts generated by the weather service that are displayed on the monitor screens. This automatically notifies staff of a potential threat. Based on this information, managers are able to make informed decisions on real-time weather conditions and how those conditions relate to the safety of its work crews. The weather data allows CEC to customize alerts to notify the proper manager of specific weather-related conditions relevant to a particular service area.

CHANGING CONDITIONS

As an example, a utility using an advanced weather service might know that its service area is currently experiencing wind gusts of 30 mph (48 kmph) with light rain; that is valuable information. But, if an alert informs staff that in a matter of two hours conditions will turn severe with 50-mph (80-kmph) winds, the manager can begin taking the proper precautions of removing crews from their outdoor work sites. Instead, the utility manager might have the crews preparing resources to begin restoration efforts directly after the storm passes.

PERSONALIZED WEATHER RELATIONSHIP

SECO Energy has more than 170,000 members in a service area totaling nearly 2000 sq miles (5180 sq km). Located on the Florida peninsula, about 75 miles (121 km) from the Atlantic Ocean, and surrounded by water, the city of Eustis experiences differential heating during the day. Tropical-like weather conditions result in more than 100 thunderstorm days a year. Weather is an undeniable factor in reliability and operations for SECO Energy, so the utility relies heavily on its specialized weather provider.

Not only does SECO receive customized weather information as an online subscription, but utility staff also make and receive personal phone calls from Telvent DTN meteorologists, who are working specifically to track weather conditions for the utility. Each day, as he drives into the office, SECO Energy's reliability and operations director speaks to his meteorologist associate in Minneapolis, who knows the needs of the utility. During severe weather events, like a tropical storm or hurricane, this communication takes place many times a day.

IN THE LIGHTNING CAPITAL

Also, because of its unique geographical location, Florida receives more lightning strikes than any other state. Central Florida even carries the nickname lightning capital of the United States. The North American Lightning Detection Network has chronicled that central Florida has the highest density of cloud-to-ground lightning strokes, with July usually being the most-active lightning period.

Because SECO Energy is located in the lightning capital, it also uses Telvent DTN's services to monitor and document all the lightning activity in its service area, to track lightning strikes as they approach its boundaries and to notify repair crews in the area. When there is an inordinate number of outages in the service, staff can quickly check the documented lightning strikes for troubleshooting and confirmation. Based on the number of lightning strikes documented, utility staff can determine how many outages to expect and how many repair crews will need to respond.

THEN THERE ARE HURRICANES

Being located near the Caribbean and in between the Gulf of Mexico and the Atlantic, Florida is always susceptible to hurricanes. However, the utility does not view the National Weather Service as a sufficient provider of accurate weather information to prepare for potential outages. While the National Weather Service provides weather information to help the general public and alerts citizens when they are in the path of severe weather, SECO Energy relies on utility-specific weather information related to its service areas and locations of interest.

The primary function of the National Weather Service is to protect lives and property, so it errs on the side of caution and issues warnings or alerts based on predetermined weather conditions, which is exactly what it should do. But from a utility perspective, it is not as useful for response efforts to know what could potentially happen given the right circumstances. For better preparation, the utility needs to know what most likely will happen based on the current weather conditions, so it can prepare repairs crews for the likely outages.

If a tropical storm or hurricane is approaching, SECO Energy deems it vital to consult with an expert meteorologist, make an accurate assessment for possible damages and determine whether or not it will need to call other states for additional restoration support. When a hurricane is approaching, SECO Energy is essentially competing with other utilities for the same resources, so the sooner it can confidently make the decision to call for help, the easier it is to get the needed reinforcements.

Also, tremendous resources can be wasted by bringing in additional repair crews, if not planned properly. It can cost millions of dollars per day to feed, house and pay contracted crews; these costs can be even higher if the hired crews are unable to work because dangerous weather conditions have not dissipated. In this instance, a good weather forecaster can literally save a utility millions of dollars.

WEATHER DATA INVESTMENT

Weather conditions will always be an uncontrollable liability. It is in the best interest of every utility to take all the necessary precautions to ensure customers receive the best-possible service. For smaller cooperative utilities, it is important to make use of the most-advanced comprehensive weather information available to successfully prepare for whatever Mother Nature brings.

Using the advanced radar and expert consulting, SECO Energy also can determine when to mobilize resources. The ability to more-accurately predict a hurricane or storm's path, speed, intensity and duration allows managers to make better decisions on when crews can safely begin restoration work.

CEC also uses its weather service provider for information that affects its daily routine work. Each morning, the operations manager reviews the customized weather reports and decides where each work crew is headed, what task they are going to accomplish and how long they should be at each site. This is another way to get the most value out of the weather service investment.

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John LaSelva (john.laselva@secoenergy.com) currently serves as the director of reliability and operations for Sumter Electric Cooperative Inc. He is responsible for transmission and distribution, substation, metering, integrated vegetation management and system operations. He started his career at SECO in 2000 in the engineering department.

Jean Thrasher (jthrasher@comelec.coop) serves as vice president of operations for Community Electric Cooperative. Thrasher has worked for CEC for more than 18 years.