Cost, safety drive line-burying decisions at Tucson Electric Power


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TEP Undergrounding Policy prioritizes selective underground power lines to manage wildfire risk, engineering costs, and ratepayer impacts, balancing transmission and distribution reliability with right-of-way, safety, and vegetation management per Arizona regulators.

 

Key Points

A selective TEP approach to bury lines where safety, engineering, and cost justify undergrounding.

✅ Selective undergrounding for feeders near substations

✅ Balances wildfire mitigation, reliability, and ratepayer costs

✅ Follows ACC rules, BLM and USFS vegetation management

 

Though wildfires in California caused by power lines have prompted calls for more underground lines, Tucson Electric Power Co. plans to keep to its policy of burying lines selectively for safety.

Like many other utilities, TEP typically doesn’t install its long-range, high-voltage transmission lines, such as the TransWest Express project, and distribution equipment underground because of higher costs that would be passed on to ratepayers, TEP spokesman Joe Barrios said.

But the company will sometimes bury lower-voltage lines and equipment where it is cost-effective or needed for safety as utilities adapt to climate change across North America, or if customers or developers are willing to pay the higher installation costs

Underground installations generally include additional engineering expenses, right-of-way acquisition for projects like the New England Clean Power Link in other regions, and added labor and materials, Barrios said.

“This practice avoids passing along unnecessary costs to customers through their rates, so that all customers are not asked to subsidize a discretionary expenditure that primarily benefits residents or property owners in one small area of our service territory,” he said, adding that the Arizona Corporation Commission has supported the company’s policy.

Even so, TEP will place equipment underground in some circumstances if engineering or safety concerns, including electrical safety tips that utilities promote during storm season, justify the additional cost of underground installation, Barrios said.

In fact, lower-voltage “feeder” lines emerging from distribution substations are typically installed underground until the lines reach a point where they can be safely brought above ground, he added.

While in California PG&E has shut off power during windy weather to avoid wildfires in forested areas traversed by its power lines after events like the Drum Fire last June, TEP doesn’t face the same kind of wildfire risk, Barrios said.

Most of TEP’s 5,000 miles of transmission and distribution lines aren’t located in heavily forested areas that would raise fire concerns, though large urban systems have seen outages after station fires in Los Angeles, he said.

However, TEP has an active program of monitoring transmission lines and trimming vegetation to maintain a fire-safety buffer zone and address risks from vandalism such as copper theft where applicable, in compliance with federal regulations and in cooperation with the U.S. Bureau of Land Management and the U.S. Forest Service.

 

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Solar Becomes #3 Renewable Electricity Source In USA

U.S. Solar Generation 2017 surpassed biomass, delivering 77 million MWh versus 64 million MWh, trailing only hydro and wind; driven by PV expansion, capacity additions, and utility-scale and small-scale growth, per EIA.

 

Key Points

It was the year U.S. solar electricity exceeded biomass, hitting 77 million MWh and trailing only hydro and wind.

✅ Solar: 77 million MWh; Biomass: 64 million MWh (2017, EIA)

✅ PV expansion; late-year capacity additions dampen annual generation

✅ Hydro: 300 and wind: 254 million MWh; solar thermal ~3 million MWh

 

Electricity generation from solar resources in the United States reached 77 million megawatthours (MWh) in 2017, surpassing for the first time annual generation from biomass resources, which generated 64 million MWh in 2017. Among renewable sources, only hydro and wind generated more electricity in 2017, at 300 million MWh and 254 million MWh, respectively. Biomass generating capacity has remained relatively unchanged in recent years, while solar generating capacity has consistently grown.

Annual growth in solar generation often lags annual capacity additions because generating capacity tends to be added late in the year. For example, in 2016, 29% of total utility-scale solar generating capacity additions occurred in December, leaving few days for an installed project to contribute to total annual generation despite being counted in annual generating capacity additions. In 2017, December solar additions accounted for 21% of the annual total. Overall, solar technologies operate at lower annual capacity factors and experience more seasonal variation than biomass technologies.

Biomass electricity generation comes from multiple fuel sources, such as wood solids (68% of total biomass electricity generation in 2017), landfill gas (17%), municipal solid waste (11%), and other biogenic and nonbiogenic materials (4%).These shares of biomass generation have remained relatively constant in recent years, even as renewables' rise in 2020 across the grid.

Solar can be divided into three types: solar thermal, which converts sunlight to steam to produce power; large-scale solar photovoltaic (PV), which uses PV cells to directly produce electricity from sunlight; and small-scale solar, which are PV installations of 1 megawatt or smaller. Generation from solar thermal sources has remained relatively flat in recent years, at about 3 million MWh, even as renewables surpassed coal in 2022 nationwide. The most recent addition of solar thermal capacity was the Crescent Dunes Solar Energy plant installed in Nevada in 2015, and currently no solar thermal generators are under construction in the United States.

Solar photovoltaic systems, however, have consistently grown in recent years, as indicated by 2022 U.S. solar growth metrics across the sector. In 2014, large-scale solar PV systems generated 15 million MWh, and small-scale PV systems generated 11 million MWh. By 2017, annual electricity from those sources had increased to 50 million MWh and 24 million MWh, respectively, with projections that solar could reach 20% by 2050 in the U.S. mix. By the end of 2018, EIA expects an additional 5,067 MW of large-scale PV to come online, according to EIA’s Preliminary Monthly Electric Generator Inventory, with solar and storage momentum expected to accelerate. Information about planned small-scale PV systems (one megawatt and below) is not collected in that survey.

 

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Tackling climate change with machine learning: Covid-19 and the energy transition

Covid-19 Energy Transition and Machine Learning reshape climate change policy, electricity planning, and grid operations, from demand forecasting and decarbonization strategies in Europe to scalable electrification modeling and renewable integration across Africa.

 

Key Points

How the pandemic reshapes energy policy and how ML improves planning, demand forecasts, and grid reliability in Africa.

✅ Pandemic-driven demand shifts strain grid operations and markets

✅ Policy momentum risks rollback; favor future-oriented decarbonization

✅ ML boosts demand prediction, electrification, and grid reliability in Africa

 

The impact of Covid-19 on the energy system was discussed in an online climate change workshop that also considered how machine learning can help electricity planning in Africa.

This year’s International Conference on Learning Representations event included a workshop held by the Climate Change AI group of academics and artificial intelligence industry representatives, which considered how machine learning can help tackle climate change and highlighted advances by European electricity prediction specialists working in this field.

Bjarne Steffen, senior researcher at the energy politics group at ETH Zürich, shared his insights at the workshop on how Covid-19 and the accompanying economic crisis are affecting recently introduced ‘green’ policies. “The crisis hit at a time when energy policies were experiencing increasing momentum towards climate action, especially in Europe, and in proposals to invest in smarter electricity infrastructure for long-term resilience,” said Steffen, who added the coronavirus pandemic has cast into doubt the implementation of such progressive policies.

The academic said there was a risk of overreacting to the public health crisis, as far as progress towards climate change goals was concerned.

 

Lobbying

“Many interest groups from carbon-intensive industries are pushing to remove the emissions trading system and other green policies,” said Steffen. “In cases where those policies are having a serious impact on carbon-emitting industries, governments should offer temporary waivers during this temporary crisis, instead of overhauling the regulatory structure.”

However, the ETH Zürich researcher said any temptation to impose environmental conditions to bail-outs for carbon-intensive industries should be resisted. “While it is tempting to push a green agenda in the relief packages, tying short-term environmental conditions to bail-outs is impractical, given the uncertainty in how long this crisis will last,” he said. “It is better to include provisions that will give more control over future decisions to decarbonize industries, such as the government taking equity shares in companies.”

Steffen shared with pv magazine readers an article published in Joule which can be accessed here, and which articulates his arguments about how Covid-19 could affect the energy transition.

 

Covid-19 in the U.K.

The electricity system in the U.K. is also being affected by Covid-19, even as the U.S. electric grid grapples with climate risks, according to Jack Kelly, founder of London-based, not-for-profit, greenhouse gas emission reduction research laboratory Open Climate Fix.

“The crisis has reduced overall electricity use in the U.K.,” said Kelly. “Residential use has increased but this has not offset reductions in commercial and industrial loads.”

Steve Wallace, a power system manager at British electricity system operator National Grid ESO recently told U.K. broadcaster the BBC electricity demand has fallen 15-20% across the U.K. The National Grid ESO blog has stated the fall-off makes managing grid functions such as voltage regulation more challenging.

Open Climate Fix’s Kelly noted even events such as a nationally-coordinated round of applause for key workers was followed by a dramatic surge in demand, stating: “On April 16, the National Grid saw a nearly 1 GW spike in electricity demand over 10 minutes after everyone finished clapping for healthcare workers and went about the rest of their evenings.”

Climate Change AI workshop panelists also discussed the impact machine learning could have on improving electricity planning in Africa. The Electricity Growth and Use in Developing Economies (e-Guide) initiative funded by fossil fuel philanthropic organization the Rockefeller Foundation aims to use data to improve the planning and operation of electricity systems in developing countries.

E-Guide members Nathan Williams, an assistant professor at the Rochester Institute of Technology (RIT) in New York state, and Simone Fobi, a PhD student at Columbia University in NYC, spoke about their work at the Climate Change AI workshop, which closed on Thursday. Williams emphasized the importance of demand prediction, saying: “Uncertainty around current and future electricity consumption leads to inefficient planning. The weak link for energy planning tools is the poor quality of demand data.”

Fobi said: “We are trying to use machine learning to make use of lower-quality data and still be able to make strong predictions.”

The market maturity of individual solar home systems and PV mini-grids in Africa mean more complex electrification plan modeling is required, similar to integrating AI data centers into Canada's grids at scale.

 

Modeling

“When we are doing [electricity] access planning, we are trying to figure out where the demand will be and how much demand will exist so we can propose the right technology,” added Fobi. “This makes demand estimation crucial to efficient planning.”

Unlike many traditional modeling approaches, machine learning is scalable and transferable. Rochester’s Williams has been using data from nations such as Kenya, which are more advanced in their electrification efforts, to train machine learning models to make predictions to guide electrification efforts in countries which are not as far down the track.

Williams also discussed work being undertaken by e-Guide members at the Colorado School of Mines, which uses nighttime satellite imagery and machine learning to assess the reliability of grid infrastructure in India, where new algorithms to prevent ransomware-induced blackouts are also advancing.

 

Rural power

Another e-Guide project, led by Jay Taneja at the University of Massachusetts, Amherst – and co-funded by the Energy and Economic Growth program on development spending based at Berkeley – uses satellite imagery to identify productive uses of electricity in rural areas by detecting pollution signals from diesel irrigation pumps.

Though good quality data is often not readily available for Africa, Williams added, it does exist.

“We have spent years developing trusting relationships with utilities,” said the RIT academic. “Once our partners realize the value proposition we can offer, they are enthusiastic about sharing their data … We can’t do machine learning without high-quality data and this requires that organizations can effectively collect, organize, store and work with data. Data can transform the electricity sector, as shown by Canadian projects to use AI for energy savings, but capacity building is crucial.”

 

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Hydro wants B.C. residents to pay an extra $2 a month for electricity

BC Hydro Rate Increase proposes a 2.3% hike from April, with BCUC review, aligning below inflation and funding clean energy, electrification, and grid upgrades across British Columbia while keeping electricity prices among North America's lowest.

 

Key Points

A proposed 2.3% BC Hydro hike from April, under BCUC review, funds clean energy and keeps average bills below inflation.

✅ Adds about $2 per month to average residential bill

✅ Sixth straight increase below inflation since 2018

✅ Supports renewable projects and grid modernization

 

The British Columbia government says the province’s Crown power utility is applying for a 2.3-per-cent rate increase starting in April, with higher BC Hydro rates previously outlined, adding about $2 a month to the average residential bill.

A statement from the Energy Ministry says it’s the sixth year in a row that BC Hydro has applied for an increase below the rate of inflation, similar to a 3 per cent rise noted in a separate approval, which still trailed inflation.

It says rates are currently 15.6 per cent lower than the cumulative rate of inflation over the last seven years, starting in 2017-2018, with a provincial rate freeze among past measures, and 12.4 per cent lower than the 10-year rates plan established by the previous government in 2013.

The ministry says the “modest” rate increase application comes after consideration of a variety of options and their long-term impacts, including scenarios like a 3.75% two-year path evaluated alongside others, and the B.C. Utilities Commission is expected to decide on the plan by the end of February.

Chris O’Riley, president of BC Hydro, says the rates application would keep electricity costs in the province among the lowest in North America, even as a BC Hydro fund surplus prompted calls for changes, while supporting investments in clean energy to power vehicles, homes and businesses.

Energy Minister Josie Osborne says it’s more important than ever to keep electricity bills down, especially as Ontario hydro rates increase in a separate jurisdiction, as the cost of living rises at rates that are unsustainable for many.

“Affordable, stable BC Hydro rates are good for people, businesses and climate as we work together to power our growing economy with renewable energy instead of fossil fuels,” Osborne says in a statement issued Monday.

Earlier this year, the ministry said BC Hydro provided $315 million in cost-of-living bill credits, while in another province Manitoba Hydro scaled back an increase to ease pressure, to families and small businesses in the province, including those who receive their electricity service from FortisBC or a municipal utility.

 

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Hydro-Quebec shocks cottage owner with $5,300 in retroactive charges

Hydro-Quebec back-billing arises from analogue meter errors and estimated consumption, leading to arrears for electricity usage; disputes over access, payment plans, and potential power diversion reviews can impact cottage owners near Gatineau.

 

Key Points

Hydro-Quebec back-billing recovers underbilled electricity from analogue meter errors or prolonged estimated use.

✅ Triggered by inaccurate analogue meters or missed readings

✅ Based on actual usage versus prior estimated consumption

✅ Payment plans may spread arrears; theft checks may adjust

 

A relaxing lakefront cottage has become a powerful source of stress for an Ottawa woman who Hydro-Quebec is charging $5,300 to cover what it says are years of undercharging for electricity usage.

The utility said an old analogue power meter is to blame for years of inaccurate electricity bills for the summer getaway near Gatineau, Que.

Separate from individual billing issues, Hydro-Quebec has also reported pandemic-related losses earlier this year.

Owner Jan Hodgins does not think she should be held responsible for the mistake, nor does she understand how her usage could have surged over the years.

“I’m very hydro conscious, because I was raised that way. When you left a room, you always turned the light out,” she told CTV Montreal on Wednesday, relating her shock after receiving some hefty bills from Hydro-Quebec on Sept. 22.

Hodgins said she mainly uses the cottage on weekends, does not heat the place when she is not there, and does not use a washer or dryer, to keep her energy footprint as small as possible. She’s owned the cottage for 14 years, during which she says her monthly bill has hovered around $40.

Hydro-Quebec said it has not had an accurate reading of her usage for several years, relying instead on consumption estimates to determine what she pays. The company recently reviewed her energy consumption back to 2014, and found their estimates were not accurate.

“In the past, she was consuming about 10 to 15 kilowatt hours per day. This summer she was more around 40 kilowatt hours per day,” Marc-Antoine Pouliot with Hydro-Quebec told CTV Ottawa.

Hodgins said that means her regular bill will now be more than twice the $200 her neighbours are paying for hydro each month, even with peak hydro rates in place.

Hydro-Quebec said it will correct the bill if its technicians discover that someone is illegally diverting power nearby.

Hodgins said it’s not her fault that technicians did not check her meter in person, and chose to rely on inaccurate estimates. Pouliot argues that reaching her cottage was too difficult.

“There was too much snow. There were conditions during the winter disconnection ban period, and the consequence was that people, our workers, were not able to reach the meter,” he said.

Hydro-Quebec said it is willing to stretch out the debt into monthly payments over a year, which Hodgins said amount to $440 per month on top of her regular bill.

Utilities also caution customers about scammers threatening shutoffs during billing disputes.

“I’m on a fixed income. I don’t have that kind of money. I’m completely distraught,” she said. “I don’t know what I’m going to do.”

 

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Ontario Sets Electricity Rates at Off-Peak Price until February 7

Ontario Off-Peak Electricity Rate offers 8.2 cents per kWh for 24 hours, supporting Time-of-Use and Tiered Regulated Price Plan customers, including residential, small business, and farms, under Ontario Energy Board guidelines during temporary relief.

 

Key Points

A temporary 8.2 cents per kWh all-day price for RPP customers, covering TOU and Tiered users across Ontario.

✅ Applies 24 hours daily at 8.2 cents per kWh for 21 days

✅ Covers residential, small business, and farm RPP customers

✅ Valid for TOU and Tiered plans set by the Ontario Energy Board

 

 The Ontario government has announced electricity relief with electricity prices set at the off-peak price of 8.2 cents per kilowatt-hour, 24 hours per day for 21 days starting January 18, 2022, until the end of day February 7, 2022, for all Regulated Price Plan customers. The off-peak rate will apply automatically to residential, small businesses and farms who pay Time-of-Use or Tiered prices set by the Ontario Energy Board.

This rate relief includes extended off-peak rates to support small businesses, as well as workers and families spending more time at home while the province is in Modified Step Two of the Roadmap to Reopen.

As part of our mandate, we set the rates that your utility charges for the electricity you use in your home or small business. These rates appear on the Electricity line of your bill, and we administer protections such as disconnection moratoriums for residential customers. We also set the Delivery rates that cover the cost to deliver electricity to most residential and small business customers.

 

Types of electricity rates

For residential and small business customers that buy electricity from their utility, there are two different types of rates (also called prices here), and Ontario also provides stable electricity pricing for larger users. The Ontario Energy Board sets both once a year on November 1:

Time-of-Use (TOU)

With TOU prices, the price depends on when you use electricity, including options like ultra-low overnight pricing that encourage off-peak use.

There are three TOU price periods:

  • Off-peak, when demand for electricity is lowest and new offerings like the Ultra-Low Overnight plan can encourage shifting usage. Ontario households use most of their electricity – nearly two thirds of it – during off-peak hours.
  • Mid-peak, when demand for electricity is moderate. These periods are during the daytime, but not the busiest times of day, and utilities like BC Hydro are exploring similar TOU structures as well.
  • On-peak, when demand for electricity is generally higher. These are the busier times of day – generally when people are cooking, starting up their computers and running heaters or air conditioners.

 

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Which of the cleaner states imports dirty electricity?

Hourly Electricity Emissions Tracking maps grid balancing areas, embodied emissions, and imports/exports, revealing carbon intensity shifts across PJM, ERCOT, and California ISO, and clarifying renewable energy versus coal impacts on health and climate.

 

Key Points

An hourly method tracing generation, flows, and embodied emissions to quantify carbon intensity across US balancing areas.

✅ Hourly traces of imports/exports and generation mix

✅ Consumption-based carbon intensity by balancing area

✅ Policy insights for renewables, coal, health costs

 

In the United States, electricity generation accounts for nearly 30% of our carbon emissions. Some states have responded to that by setting aggressive renewable energy standards; others are hoping to see coal propped up even as its economics get worse. Complicating matters further is the fact that many regional grids are integrated, and as America goes electric the stakes grow, meaning power generated in one location may be exported and used in a different state entirely.

Tracking these electricity exports is critical for understanding how to lower our national carbon emissions. In addition, power from a dirty source like coal has health and environment impacts where it's produced, and the costs of these aren't always paid by the parties using the electricity. Unfortunately, getting reliable figures on how electricity is produced and where it's used is challenging, even for consumers trying to find where their electricity comes from in the first place, leaving some of the best estimates with a time resolution of only a month.

Now, three Stanford researchers—Jacques A. de Chalendar, John Taggart, and Sally M. Benson—have greatly improved on that standard, and they have managed to track power generation and use on an hourly basis. The researchers found that, of the 66 grid balancing areas within the United States, only three have carbon emissions equivalent to our national average, and they have found that imports and exports of electricity have both seasonal and daily changes. de Chalendar et al. discovered that the net results can be substantial, with imported electricity increasing California's emissions/power by 20%.

Hour by hour
To figure out the US energy trading landscape, the researchers obtained 2016 data for grid features called balancing areas. The continental US has 66 of these, providing much better spatial resolution on the data than the larger grid subdivisions. This doesn't cover everything—several balancing areas in Canada and Mexico are tied in to the US grid—and some of these balancing areas are much larger than others. The PJM grid, serving Pennsylvania, New Jersey, and Maryland, for example, is more than twice as large as Texas' ERCOT, in a state that produces and consumes the most electricity in the US.

Despite these limitations, it's possible to get hourly figures on how much electricity was generated, what was used to produce it, and whether it was used locally or exported to another balancing area. Information on the generating sources allowed the researchers to attach an emissions figure to each unit of electricity produced. Coal, for example, produces double the emissions of natural gas, which in turn produces more than an order of magnitude more carbon dioxide than the manufacturing of solar, wind, or hydro facilities. These figures were turned into what the authors call "embodied emissions" that can be traced to where they're eventually used.

Similar figures were also generated for sulfur dioxide and nitrogen oxides. Released by the burning of fossil fuels, these can both influence the global climate and produce local health problems.

Huge variation
The results were striking. "The consumption-based carbon intensity of electricity varies by almost an order of magnitude across the different regions in the US electricity system," the authors conclude. The low is the Bonneville Power grid region, which is largely supplied by hydropower; it has typical emissions below 100kg of carbon dioxide per megawatt-hour. The highest emissions come in the Ohio Valley Electric region, where emissions clear 900kg/MW-hr. Only three regional grids match the overall grid emissions intensity, although that includes the very large PJM (where capacity auction payouts recently fell), ERCOT, and Southern Co balancing areas.

Most of the low-emissions power that's exported comes from the Pacific Northwest's abundant hydropower, while the Rocky Mountains area exports electricity with the highest associated emissions. That leads to some striking asymmetries. Local generation in the hydro-rich Idaho Power Company has embodied emissions of only 71kg/MW-hr, while its imports, coming primarily from Rocky Mountain states, have a carbon content of 625kg/MW-hr.

The reliance on hydropower also makes the asymmetry seasonal. Local generation is highest in the spring as snow melts, but imports become a larger source outside this time of year. As solar and wind can also have pronounced seasonal shifts, similar changes will likely be seen as these become larger contributors to many of these regional grids. Similar things occur daily, as both demand and solar production (and, to a lesser extent, wind) have distinct daily profiles.

The Golden State
California's CISO provides another instructive case. Imports represent less than 30% of its total electric use in 2016, yet California electricity imports provided 40% of its embodied emissions. Some of these, however, come internally from California, provided by the Los Angeles Department of Water and Power. The state itself, however, has only had limited tracking of imported emissions, lumping many of its sources as "other," and has been exporting its energy policies to Western states in ways that shape regional markets.

Overall, the 2016 inventory provides a narrow picture of the US grid, as plenty of trends are rapidly changing our country's emissions profile, including the rise of renewables and the widespread adoption of efficiency measures and other utility trends in 2017 that continue to evolve. The method developed here can, however, allow for annual updates, providing us with a much better picture of trends. That could be quite valuable to track things like how the rapid rise in solar power is altering the daily production of clean power.

More significantly, it provides a basis for more informed policymaking. States that wish to promote low-emissions power can use the information here to either alter the source of their imports or to encourage the sites where they're produced to adopt more renewable power. And those states that are exporting electricity produced primarily through fossil fuels could ensure that the locations where the power is used pay a price that includes the health costs of its production.

 

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