Explaining the KUBÂ’s tree-trimming policy

By J. Thomas Jones, Knoxville News Sentinel


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Recent media and community attention has focused on the Knoxville Utilities Board's tree-trimming practices. In taking a look at the issue, there are basically two fundamental questions: Should KUB trim trees away from electric lines? If so, how?

Should KUB trim trees away from electric lines?

Yes, absolutely so. Tree trimming is necessary because of the simple fact that trees conduct electricity.

We all know it's dangerous to take chances with electricity — no one would think of touching a live electric wire. What you may not realize is that a tree that contacts an electric line can be nearly as dangerous as the line itself.

The risk is very real. It would be irresponsible for KUB to ignore this risk, and that is the primary reason that we spend $6 million every year to keep trees a safe distance away from the lines.

In addition to safety, tree trimming is necessary to provide reliable electric service. Even the smallest branch can cause an outage, often affecting residences nowhere near the initial event. Reliable service is a benchmark recognized in the industry; more than that, it's what our customers expect and deserve, and KUB takes that responsibility very seriously.

How should trees be trimmed?

KUB welcomes input from the community as to the best practices to be employed. Some background is helpful in terms of considering KUB's current practices.

In the industry, 10 feet is generally accepted as a minimum clearance around an electric distribution line like those found in most neighborhoods. For higher voltage transmission lines, a larger clearance (generally 25 feet) is needed.

For many years, KUB trimmed as little as possible in order to maintain the minimum clearance and preserve the aesthetic appearance of the tree. However, in doing so, the health of the tree was sometimes put at risk, because the location of the cut resulting from pruning the branch or limb could have an effect on the tree's overall health.

In 1991, the city of Knoxville took steps to become a Tree City, a designation granted by the Arbor Day Foundation. After learning about it from the city administration, KUB applied for a similar designation for utilities — the Tree Line USA designation.

To become a Tree Line Utility, KUB's tree trimming practices were modified to make the health of the tree a priority over aesthetics. This means that sometimes more of a tree is trimmed than is necessary for a minimum clearance because it is healthier for the tree.

KUB has been recognized as a Tree Line Utility by the Arbor Day Foundation every year since 2001, and KUB's tree trimming policies and practices are reviewed annually in connection with this recognition.

All that said, KUB has seen the benefits of customer input to our program. In fact, we've already made numerous improvements as a result of feedback from our customers.

We adopted a modified tree-trimming approach for mature canopy trees in response to community requests. We have improved customer communications by increasing the use of door hangers, face-to-face meetings with individual customers, neighborhood-wide notices and meetings, and even an interactive map on KUB's Web site.

We employ three full-time employees certified as arborists and as utility foresters. And, in response to recent community dialog, we are establishing a 15-person Tree Trim Policy Review Panel to continue to evaluate issues that relate to tree trimming. We look forward to the recommendations the panel will bring to us later this year.

KUB is governed by a seven-person citizen board. We are native Knoxvillians and newcomers, and the board's diverse makeup reflects the community we serve. We care about Knoxville, and we do our best to balance the many aesthetic, operational and financial issues involved in delivering safe and reliable utility services to our customers.

With more than 5,200 miles of electric line, 1,400 miles of water line, 1,300 miles of sewer line and 2,300 miles of gas line to maintain, it's a difficult balancing act, and we can't please everyone.

As mentioned above, we really do try our best, and we're always willing to listen and learn as we strive to continually improve service to our customers.

The author J. Thomas Jones is a West Hills resident and an attorney in private practice in Knoxville. He has served on the KUB board since 1998 and is concluding his third and final year as board chair.

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"Knowledge Gap" Is Contributing To On-the-job Electrical Injuries

BC Hydro Trades Electrical Safety addresses electric contact incidents among trade workers, emphasizing power line hazards, overhead lines clearance, the 3 m rule, jobsite planning, and safety training to prevent injuries during spring and summer.

 

Key Points

BC Hydro Trades Electrical Safety is guidance and training to reduce power-line contact risks for trade workers.

✅ Stay at least 3 m from overhead power lines and equipment

✅ Plan worksites and spot hazards before starting tasks

✅ Use BC Hydro electrical awareness training near electricity

 

A BC Hydro report finds serious electrical contact incidents are more common among trades workers, and research shows this is partly due to a knowledge gap in the electricity sector in Canada.

Trade workers were involved in more than 60 per cent of electric contact incidents that led to serious injuries over the last three years, according to BC Hydro.

One-in-five trade workers have also either made contact or had a close call with electric equipment.

A recent worksite electrocution case underscores the consequences of contact.

“New research finds many have had a close call with electricity on the job or have witnessed unsafe work near overhead lines or electrical equipment,” BC Hydro staff said in the report.

“A gap in electrical safety knowledge is a contributing factor in most of these incidents.”

Most electrical contact incidents take place in the spring and summer, when trade workers are working outdoors and are working in close proximity to power lines.

BC Hydro offered tips for trades workers who may work closely to possible electrical contact points:

  • Look up and down – Observe the site beforehand and plan work so you can avoid contact with power lines
  • Stay back – You and your tools should stay at least 3 m away from an overhead power line
  • Call for help – If you come across a fallen power line, or a tree branch or object contacts a line—stay back 10 metres and call 911. Never try and move it yourself. If you must work closer than 3 m to a power line at your worksite, call BC Hydro before you begin.
  • Learn about the risks – BC Hydro offers in-person and online electrical awareness training, such as arc flash training, for anyone who works near electricity.

The report found that 38 per cent of trades workers who participated in the report said they only feel “somewhat informed” about safety measures around working near electricity and 71 per cent were unable to identify the correct distance they should be away from active power lines or electrical equipment.

BC Hydro said trade workers should participate in its electrical awareness training courses, including arc flash training, to make sure all safety measures are taken.

 

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N.S. approves new attempt to harness Bay of Fundy's powerful tides

Bay of Fundy Tidal Energy advances as Nova Scotia permits Jupiter Hydro to test floating barge platforms with helical turbines in Minas Passage, supporting renewable power, grid-ready pilots, and green jobs in rural communities.

 

Key Points

A Nova Scotia tidal energy project using helical turbines to generate clean power and create local jobs.

✅ Permits enable 1-2 MW prototypes near Minas Passage

✅ Floating barge platforms with patented helical turbines

✅ PPA at $0.50/kWh with Nova Scotia Power

 

An Alberta-based company has been granted permission to try to harness electricity from the powerful tides of the Bay of Fundy.

Nova Scotia has issued two renewable energy permits to Jupiter Hydro.

Backers have long touted the massive energy potential of Fundy's tides -- they are among the world's most powerful -- but large-scale commercial efforts to harness them have borne little fruit so far, even as a Scottish tidal project recently generated enough power to supply nearly 4,000 homes elsewhere.

The Jupiter application says it will use three "floating barge type platforms" carrying its patented technology. The company says it uses helical turbines mounted as if they were outboard motors.

"Having another company test their technology in the Bay of Fundy shows that this early-stage industry continues to grow and create green jobs in our rural communities," Energy and Mines Minister Derek Mombourquette said in a statement.

The first permit allows the company to test a one-megawatt prototype that is not connected to the electricity grid.

The second -- a five-year permit for up to two megawatts -- is renewable if the company meets performance standards, environmental requirements and community engagement conditions.

Mombourquette also authorized a power purchase agreement that allows the company to sell the electricity it generates to the Nova Scotia grid through Nova Scotia Power for 50 cents per kilowatt hour.

On its web site, Jupiter says it believes its approach "will prove to be the most cost effective marine energy conversion technology in the world," even as other regional utilities consider initiatives like NB Power's Belledune concept for turning seawater into electricity.

The one megawatt unit would have screws which are about 5.5 metres in diameter.

The project is required to obtain all other necessary approvals, permits and authorizations.

It will be located near the Fundy Ocean Research Center for Energy in the Minas Passage and will use existing electricity grid connections.

A study commissioned by the Offshore Energy Research Association of Nova Scotia says by 2040, the tidal energy industry could contribute up to $1.7 billion to Nova Scotia's gross domestic product and create up to 22,000 full-time jobs, a transition that some argue should be planned by an independent body to ensure reliability.

Last month, Nova Scotia Power said it now generates 30 per cent of its power from renewables, as the province moves to increase wind and solar projects after abandoning the Atlantic Loop.

The utility says 18 per cent came from wind turbines, nine per cent from hydroelectric and tidal turbines and three per cent by burning biomass across its fleet.

However, over half of the province's electrical generation still comes from the burning of coal or petroleum coke, even as environmental advocates push to reduce biomass use in the mix. Another 13 per cent come from burning natural gas and five per cent from imports.

 

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Niagara Falls Powerhouse Gets a Billion-Dollar Upgrade for the 21st Century

Sir Adam Beck I refurbishment boosts hydropower capacity in Niagara, upgrading turbines, generators, and controls for Ontario Power Generation. The billion-dollar project enhances grid reliability, clean energy output, and preserves heritage architecture.

 

Key Points

An OPG upgrade of the historic Niagara plant to replace equipment, add 150 MW, and extend clean power life.

✅ Adds at least 150 MW to Ontario's clean energy supply

✅ Replaces turbines, generators, transformers, and controls

✅ Creates hundreds of skilled construction and engineering jobs

 

Ontario's iconic Sir Adam Beck hydroelectric generating station in Niagara is set to undergo a massive, billion-dollar refurbishment. The project will significantly boost the power station's capacity and extend its lifespan, with efforts similar to revitalizing older dams seen across North America, ensuring a reliable supply of clean energy for decades to come.


A Century of Power Generation

The Sir Adam Beck generating stations have played a pivotal role in Ontario's power grid for over a century. The first generating station, Sir Adam Beck I, went online in 1922, followed by Sir Adam Beck II in 1954. A third station, the Sir Adam Beck Pump Generating Station, was added in 1957, highlighting the role of pumped storage in Ontario for grid flexibility, Collectively, they form one of the largest hydroelectric complexes in the world, harnessing the power of the Niagara River.


Preparing for Increased Demand

The planned refurbishment of Sir Adam Beck I is part of Ontario Power Generation's broader strategy, which includes the life extension at Pickering NGS among other initiatives, to meet the growing energy demands of the province. With the population expanding and a shift towards electrification, Ontario will need to increase its power generation capacity while also focusing on sustainable and clean sources of energy.


Billions to Secure Sustainable Energy

The project to upgrade Sir Adam Beck I carries a hefty price tag of over a billion dollars but is considered a vital investment in Ontario's energy infrastructure, and recent OPG financial results underscore the utility's capacity to manage long-term capital plans. The refurbishment will see the replacement of aging turbines, generators, and transformers, and a significant upgrade to the station's control systems. Following the refurbishment, the output of Sir Adam Beck I is expected to increase by at least 150 megawatts – enough to power thousands of homes and businesses.


Creating Green Jobs

In addition to securing the province's energy future, the upgrade presents significant economic benefits to the Niagara region. The project will create hundreds of well-paying construction and engineering jobs, similar to employment from the continued operation of Pickering Station across Ontario, during the several years it will take to implement the upgrades.


Commitment to Hydropower

Ontario Power Generation (OPG) has long touted the benefits of hydropower as a reliable, renewable, and affordable source of energy, even as an analysis of rising grid emissions underscores the importance of clean generation to meet demand. The Sir Adam Beck complex is a shining example and represents a significant asset in the fight against climate change while providing reliable power to Ontario's businesses and residents.


Balancing Energy Needs with Heritage Preservation

The refurbishment will also carefully integrate modern design with the station's heritage elements, paralleling decisions such as the refurbishment of Pickering B that weigh system needs and public trust. Sir Adam Beck I is a designated historic site, and the project aims to preserve the station's architectural significance while enhancing its energy generation capabilities.

 

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Fixing California's electric grid is like repairing a car while driving

CAISO Clean Energy Transition outlines California's path to 100% carbon-free power by 2045, scaling renewables, battery storage, and offshore wind while safeguarding grid reliability, managing natural gas, and leveraging Western markets like EDAM.

 

Key Points

CAISO Clean Energy Transition is the plan to reach 100% carbon-free power by 2045 while maintaining grid reliability.

✅ Target: add 7 GW/year to reach 120 GW capacity by 2045

✅ Battery storage up 30x; smooths intermittent solar and wind

✅ EDAM and WEIM enhance imports, savings, and reliability

 

Mark Rothleder, Chief Operating Officer and Senior Vice President at the California Independent System Operator (CAISO), which manages roughly 80% of California’s electric grid, has expressed cautious optimism about meeting the state's ambitious clean energy targets while keeping the lights on across the grid. However, he acknowledges that this journey will not be without its challenges.

California aims to transition its power system to 100% carbon-free sources by 2045, ensuring a reliable electricity supply at reasonable costs for consumers. Rothleder, aware of the task's enormity, likens it to a complex car repair performed while the vehicle is in motion.

Recent achievements have demonstrated California's ability to temporarily sustain its grid using clean energy sources. According to Rothleder, the real challenge lies in maintaining this performance round the clock, every day of the year.

Adding thousands of megawatts of renewable energy into California’s existing 50-gigawatt system, which needs to expand to 120 gigawatts to meet the 2045 goal, poses a significant challenge, though recent grid upgrade funding offers some support for needed infrastructure. CAISO estimates that an addition of 7 gigawatts of clean power per year for the next two decades is necessary, all while ensuring uninterrupted power delivery.

While natural gas currently constitutes California's largest single source of power, Rothleder notes the need to gradually decrease reliance on it, even as it remains an operational necessity in the transition phase.

In 2023, CAISO added 5,660 megawatts of new power to the grid, with plans to integrate over 1,100 additional megawatts in the next six to eight months of 2024. Battery storage, crucial for mitigating the intermittent nature of wind and solar power, has seen substantial growth as California turns to batteries for grid support, increasing 30-fold in three years.

Rothleder emphasizes that electricity reliability is paramount, as consumers always expect power availability. He also highlights the potential of offshore wind projects to significantly contribute to California's power mix by 2045.

The offshore wind industry faces financial and supply chain challenges despite these plans. CAISO’s 20-year outlook indicates a significant increase in utility-scale solar, requiring extensive land use and wider deployment of advanced inverters for grid stability.

Addressing affordability is vital, especially as California residents face increasing utility bills. Rothleder suggests a broader energy cost perspective, encompassing utility and transportation expenses.

Despite smooth grid operations in 2023, challenges in previous years, including extreme weather-induced power outages driven by climate change, underscore the need for a robust, adaptable grid. California imports about a quarter of its power from neighbouring states and participates in the Western Energy Imbalance Market, which has yielded significant savings.

CAISO is also working on establishing an extended day-ahead electricity market (EDAM) to enhance the current energy market's success, building on insights from a Western grid integration report that supports expanded coordination.

Rothleder believes that a thoughtfully designed, diverse power system can offer greater reliability and resilience in the long run. A future grid reliant on multiple, smaller power sources such as microgrids could better absorb potential losses, ensuring a more reliable electricity supply for California.

 

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APS asks customers to conserve energy after recent blackouts in California

Arizona Energy Conservation Alert urges APS and TEP customers to curb usage during a heatwave, preventing rolling blackouts, easing peak demand, and supporting grid reliability by raising thermostats, delaying appliances, and pausing pool pumps.

 

Key Points

A utility request during extreme heat to cut demand and protect grid reliability, helping prevent outages.

✅ Raise thermostats to 80 F or higher during peak hours

✅ Delay washers, dryers, dishwashers until after 8 p.m.

✅ Pause pool pumps; switch off nonessential lights and devices

 

After excessive heat forced rolling blackouts for thousands of people across California Friday and Saturday, Arizona Public Service Electric is asking customers to conserve energy this afternoon and evening.

“Given the extended heat wave in the western United States and climate-related grid risks that utilities are monitoring, APS is asking customers to conserve energy due to extreme energy demand that is driving usage higher throughout the region with today’s high temperatures,” APS said in a statement.

Tucson Electric Power has made a similar request of customers in its coverage area.


APS is asking customers to conserve energy in the following ways Tuesday until 8 p.m.:

  • Raise thermostat settings to no lower than 80 degrees.
  • Turn off extra lights and avoid use of discretionary major appliances such as clothes washers, dryers and dishwashers.
  • Avoid operation of pool pumps.

The request from APS also came just hours after Arizona Corporation Commission Chairman Bob Burns sent a letter to electric utilities under the commission's umbrella, like APS, to see if they are in good shape or anticipate any problems given looming shortages in California. He requested the companies respond by noon Friday.


"The whole plan is to take a look at the system early in the Summer," Burns said. "Early May we look at the system, make sure we're ready and able to serve the public throughout the entire heat cycle."

Burns told ABC15 the Summer Preparedness workshop with utilities took place in May and the regulated utilities reported they were well equipped to meet the anticipated peaks of the Summer, even as supply-chain pressures mount across the industry. Tuesday's letter to the electric companies seeks to see if they are still able to "adequately, safely and reliably" serve customers through the heatwave, or if what happened in California could take place here.

"With the activities that are occurring over in California, including tight grid conditions that have repeatedly tested operators, we just want to double check," Burns said.

An APS representative told ABC15 they have adequate supply and reserve and don't anticipate any problems.

However, the rolling blackouts in California also caught the attention of Commissioner Lea Marquez Peterson. She is calling on the chairman to hold an emergency meeting amid wildfire concerns across California and the region.

"The risk to Arizonans and the fact that energy could be interrupted, that we had some kind of rolling blackout like California would have, would be really a public health issue," Peterson said. "It could be life and death in some cases for vulnerable populations."

 

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Yukon receives funding for new wind turbines

Yukon Renewable Energy Funding backs wind turbines, grid-scale battery storage, and transmission line upgrades, cutting diesel dependence, lowering greenhouse gas emissions, and strengthening Yukon Energy's isolated grid for remote communities, local jobs, and future growth.

 

Key Points

Federal support for Yukon projects adding wind, battery storage, and grid upgrades to cut diesel use and emissions.

✅ Three 100 kW wind turbines will power Destruction Bay.

✅ 8 MW battery storage smooths peaks and reduces diesel.

✅ Mayo-McQuesten 138 kV line upgrade boosts reliability.

 

Kluane First Nation in Yukon will receive a total of $3.1 million in funding from the federal government to install and operate wind turbines that will help reduce the community’s diesel reliance.

According to a release, the community will integrate three 100-kilowatt turbines in Destruction Bay, Yukon, providing a renewable energy source for their local power grid that will reduce greenhouse gas emissions and create local jobs in the community.

A $2-million investment from Natural Resources Canada came from the Clean Energy for Rural and Remote Communities Program, part of the Government of Canada’s Investing in Canada infrastructure plan, which supports green energy solutions across jurisdictions. Crown-Indigenous Relations’ and Northern Affairs Canada also contributed a $1.1-million investment from the Northern REACHE Program.

Also, the Government of Canada announced more than $39.2 million in funding for two Yukon Energy projects that will increase the reliability of Yukon’s electrical grid, including exploration of a potential connection to the B.C. grid to bolster resiliency, and help build the robust energy system needed to support future growth. The investment comes from the government’s Green Infrastructure Stream (GIS) of the Investing in Canada infrastructure plan.

 

Project 1: Grid-scale battery storage

The federal government is investing $16.5 million in Yukon Energy’s construction of a new battery storage system in Yukon. Once completed, the 8 MW battery will be the largest grid-connected battery in the North, and one of the largest in Canada, alongside major Ontario battery projects underway.

The new battery is a critical investment in Yukon Energy’s ability to meet growing demands for power and securing Yukon’s energy future. As an isolated grid, one of the largest challenges Yukon Energy faces is meeting peak demands for power during winter months, as electrification grows with EV adoption in the N.W.T. and beyond.

When complete, the new system will store excess electricity generated during off-peak periods, complementing emerging vehicle-to-grid integration approaches, and provide Yukoners with access to more power during peak periods. This new energy storage system will create a more reliable power supply and help reduce the territory’s reliance on diesel fuel. Over the 20-year life of project, the new battery is expected to reduce carbon emissions in Yukon by more than 20,000 tonnes.

A location for the new battery energy storage system has not been identified. Yukon Energy will begin permitting of the project in 2020 with construction targeted to be complete by mid-2023.

 

Project 2: Replacing and upgrading the Mayo to McQuesten Transmission Line

Yukon Energy has received $22.7 million in federal funding to proceed with Stage 1 of the Stewart to Keno City Transmission Project – replacing and upgrading the 65 year-old transmission line between Mayo and McQuesten. The project also includes the addition of system protection equipment at the Stewart Crossing South substation. The Yukon government, through the Yukon Development Corporation, has already provided $3.5 million towards planning for the project.

Replacing the Mayo to McQuesten transmission line is critical to Yukon Energy’s ability to deliver safe and reliable electricity to customers in the Mayo and Keno regions, mirroring broader regional transmission initiatives that enhance grid resilience, and to support economic growth in Yukon. The transmission line has reached end-of-life and become increasingly unreliable for customers in the area.

The First Nation of Na-Cho Nyak Dun has expressed their support of this project. The project has also been approved by the Yukon Environmental and Socio-Economic Assessment Board.

Yukon Energy will begin replacing and upgrading the 31 km transmission line between Mayo and McQuesten in 2020. Construction is expected to be complete in late 2020. When finished, the new 138 kV transmission line will provide more reliable electricity to customers in the Mayo and Keno regions and be equipped to support industrial growth and development in the area, including the Victoria Gold Mine, with renewable power from the Yukon grid.

Planning work for the remainder of the Stewart to Keno City Transmission Project has been completed. Yukon Energy continues to explore funding opportunities that are needed to proceed with other stages of the project.

 

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