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For most of us, it is hard to imagine a life without electricity, yet behind your light switch exists one of the greatest infrastructure systems ever built. Our nation's electric grid traces its origins back to the 1880's, shortly after Thomas Edison's development of a commercially viable electric light bulb. However, our grid has evolved far beyond anything Edison could have imagined – growing into the single largest interconnected machine on the planet.
The whole of the grid consists of 450,000 miles of high voltage transmission lines and approximately six million miles of distribution lines serving nearly 300 million consumers. These lines carry electricity generated by 19,745 individual generators - 5,800 of which are considered "major" power plants. Its scale is immense and the work it does is nearly unimaginable, so much so the National Academy of Engineering voted the U.S. electrical grid the greatest feat of engineering in the 20th century.
Like many of the great engineering marvels responsible for growing the United States, the nation's electric infrastructure is showing its age but perhaps not in the way you may think. As a nation, we are asking more of our grid now than at any time in history. While demand for electricity is up, challenges that include integrating a growing portfolio of renewable energy and protecting the grid from physical and cyber threats were issues unimagined during Edison's time.
One of the great opportunities technological advances offer the grid is an increase in resilience. Resilience refers to the capability of the grid to heal itself through the use of a coordinated network of automated switches. The goal of a resilient grid is to isolate an outage before it can trigger a regional blackout such as occurred on the East Coast in 2003.
The challenge posed to this and other modernization efforts is related to the way the grid evolved. Because our nation's population grew sporadically, considerations of infrastructure often came as an afterthought. As a result the early grid looked like a series of islands. Population and the grid eventually filled in the spaces between over time, however, coordinating the system to work together is no small feat.
Probably the most amazing part is that all of this coordination happens invisibly, behind the switch and often taken for granted.
Closer to home, Missoula Electric and its members rely on the transmission system of our wholesale power provider – Bonneville Power Administration (BPA). BPA operates over 15,000 miles of high voltage transmission lines primarily located in Washington, Oregon, Idaho and Montana. These lines not only provide energy to cooperatives, municipalities and public utility districts, they provide a conduit to energy markets beyond the BPA footprint.
For more than 75 years, BPA has worked to keep the power flowing from the many resources located in the Columbia River basin. However, like the nation as a whole, BPA's transmission grid is aging and in need of maintenance and modernization.
While BPA's large steel transmission towers are a familiar site, the agency also maintains more than 4,700 miles of transmission supported by wood poles. Additionally, more than 40 percent of BPAs system is more than 50 years old, with 12 percent being more than 60 years old. To that end, BPA developed a capital investment plan that prioritizes $9 billion in work over a 10-year period to ensure the continued performance of their system.
The need for flexibility in BPAs grid comes from the requirement to integrate and balance more than 4,800 megawatts of renewable energy into the mix. BPA's transmission system was born of the need to tie together the many dams along the Columbia River and its tributaries in order to maximize the benefit of the hydroelectric resources for the region.
At the level of the Cooperative, Missoula Electric formalized its reliability effort under the banner of the Strategic Maintenance and Reliability Taskforce program, or SMART for short. In general terms, the SMART program is a pole to pole, enclosure to enclosure assessment of our system, where every piece of our equipment will be visited, evaluated and corrected if necessary.
Reliability has always been part of what we do, however the SMART program added a strategic focus where problem areas are identified by data we keep on outages and blinks. These areas are prioritized and a schedule is created to address the given area, normally by working on a specific distribution circuit.
The type of work we do as part of the SMART program includes: visual inspection, tree trimming, pole testing and replacement, tightening connections, installing animal guards and wire coverings, adding lightning arrestors and replacing cracked or chipped porcelain components.
While it is an unfortunate truth that even the most robust reliability program cannot protect against severe weather events, in the areas addressed by the SMART program, blinks and nuisance outages have fallen dramatically. The goal of the program is to cover the entire service territory in the first phase while subsequent phases will focus on maintaining the work accomplished initially. Reliability is a top priority and will remain so for decades to come.
As our industry evolves, Missoula Electric and distribution cooperatives nationwide will continue to evolve right along with it by adapting to changes in technology as well as to our members evolving wants and needs. A prime example is the rise of distributed generation – both member-owned solar and wind installations and our Missoula Electric Community Solar array in Lolo. Having a grid that is flexible and adaptive will be the key to handling the integration of today's technology as well as those not yet imagined.
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