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Conway, Ark., APPA-Funded Study Finds No Harmful Harmonics From Residential Solar

May 4, 2022

by APPA News
May 4, 2022

A study of residential solar power installations by Conway Corp. in Arkansas found that they did not generate harmonic patterns harmful to the public power utility’s electric system.

The study was done with financial support from the American Public Power Association’s Demonstration of Energy & Efficiency Developments (DEED) program.

“Our staff became aware of solar system harmonics while working on a 1-megawatt distributed energy resource solar project in 2019-2020,” Ronson Smith, electric systems engineer at Conway Corp., said via email.

Irregular loads, such as computer and solar power equipment, can create harmonic patterns that interfere with the smooth sine curve of non-linear loads and can damage the distribution grid by causing equipment to overheat or by creating the risk of disruptions or fires.

The utility’s engineers and technicians began to wonder if residential solar installations would also produce harmonic distortion. In particular, they were concerned that a large number of grid-connected solar photovoltaic inverters on a distribution network could cause power quality problems, especially since utility professionals know little about the effects of harmonics-generating equipment when it is widely distributed on a power grid.

For the study, 2021-Case Study: The Presence of Residential-Class Photovoltaic Induced Harmonics on the Distribution Network, Conway Corp. worked closely with E2C Engineering’s Electrical Consulting Engineers and hired two interns from a local university to test the individual harmonic distortion and total harmonic distortion limits on single phase residential houses with solar panels, as well as residential homes with solar panels and LED lighting.

Monitoring equipment collected data at various net metering test sites at varying degrees of magnitude on the electrical network.

The workers measured the harmonics in the same conditions while the solar system was turned off and then, during a similar period under similar conditions, with the solar system turned on to determine whether the solar system was creating harmful harmonics.

“We found that the harmonics generated are within the limits of the national standards such as IEEE-519 no matter the size PV solar system installed,” the utility said in its DEED report.

More specifically, the study showed that the typical total voltage distortion level from a house with a solar system was around 1.5 percent while the same house without the solar system connected had total voltage distortion of about 1.3 percent.

APPA’s DEED program awarded $45,520 to Conway Corp. on Oct. 2, 2020, and the project concluded on March 31, 2022. Conway Corp. contributed $71,531 to the cost of the project.

“This study will be a foundational building block for our knowledge and approach to power quality related to residential loads, as well as solar projects in general,” and it “will serve as a template for other possible power quality studies if needed in the future,” Smith said.

Conway is a quickly-growing city where more and more homes are installing solar power systems. While the utility does not have any current plans to make any changes to its net metering program based on the study results, it said it would continue to monitor the harmonics produced in different circumstances, as well as the harmonics from existing and new solar farms.

The data and analysis that came out of the study “will be helpful going forward with planning and operations,” Smith said. “It also enhanced the staffs’ understanding of net metering, solar power, and power quality.” And, Smith said, “we were able to engage local university students with a valuable internship experience at a municipal utility.”

The APPA-funded study will also provide other utilities with insight into the operational characteristics of residential solar, Smith said. “It could also give them a leg up on data and analysis strategies for similar challenges they may encounter in their own parts of the power grid.”

Nebraska Village Earns Award For Electric Distribution System Upgrade

May 4, 2022

by Paul Ciampoli
APPA News Director
May 4, 2022

The Village of Shickley, Neb., recently received a Project of the Year award from NMPP Energy for the village’s electric distribution system upgrade.

NMPP Energy presented its Project of the Year Awards to four communities at its annual conference in Lincoln, Neb., in late March.

The awards are presented annually to NMPP Energy communities to recognize projects or programs that create a more cohesive community, whether it was a project created for the entire community or one that makes it easier for city staff and employees to serve their customers. The award winners received $200 to be used for a community project of their choice.

The Village of Shickley’s project consisted of upgrading four blocks of the village’s 1950s-era electric distribution infrastructure to today’s modern standards. The project was completed in the summer of 2021.

“A safe and reliable electrical distribution system is very important to the Village of Shickley,” said Bart Brinkman, a village board member.

The village collaborated with Great Plains Power and local business Frieden Electric Company on the project.

The upgrade included installing a significantly higher voltage three-phase distribution system. Several secondary overhead wires were rerouted to clear buildings and new transformers, poles and other equipment installed that will improve system reliability and minimize maintenance for many years.

Nebraska-based NMPP Energy is a coalition of four organizations serving nearly 200 Midwest and Rocky Mountain communities.

NMPP Energy organizations include Nebraska Municipal Power Pool, Municipal Energy Agency of Nebraska, National Public Gas Agency and Public Alliance for Community Energy.

New York Power Authority Eyes Bulk-Scale Battery Storage Projects

May 4, 2022

by Paul Ciampoli
APPA News Director
May 4, 2022

The New York Power Authority (NYPA) recently issued a request for proposals (RFP) for the potential use of peaker plant sites and related electric infrastructure for the development of bulk-scale battery storage projects.

NYPA said that the RFP release comes after the review of promising study results indicating that NYPA’s peaker plants located in New York City could begin the transition to low or zero carbon emission technologies well ahead of NYPA’s VISION2030 goal of decarbonization by 2035 and the state’s goal of a zero-emission electricity sector by 2040.

The NYPA Small Clean Power Plant Adaptation Study, prepared in consultation with the PEAK Coalition, a group of environmental justice and clean energy advocates, demonstrates that four-hour duration battery storage has the potential to replace the energy currently provided by NYPA’s individual plants, if certain key conditions are met, by 2030, NYPA said.

The study was commissioned by NYPA to analyze potential clean energy options to decarbonize NYPA’s peaker plants.

Study researchers examined energy forecasts of changes in the New York electric supply mix as well as changes in demand over the next two decades, showing that as early as 2030, with the advent of more renewable energy coming into New York City, and a resulting decrease in the expected frequency and duration of run times, four-hour energy storage could provide enough energy to fully replace the operations of each individual small clean power plant unit.

NYPA said that the implementation of these technologies has the potential to also help accelerate progress in attaining the clean energy goals outlined in New York State’s Climate Leadership and Community Protection Act, legislation that calls for zero-emission electricity in New York State by 2040 and are complimentary to Governor Hochul’s 2022 State of the State commitment to phase out New York City’s older, most-polluting fossil-fuel facilities by exploring ways to repurpose and redevelop fossil-based electric infrastructure by 2030. 

Further study will be needed to assess resiliency and reliability impacts at the plant level, as well as capacity requirements required by the New York Independent System Operator and Con Edison, the investor-owned utility that provides direct energy services to New York City residents.

Additional analysis will also be needed to ensure that any envisioned retrofit, replacement or retirement does not result in an increase in carbon emissions or other criteria pollutants from less efficient fossil-fired power plants in New York City, NYPA noted.

In 2001, NYPA installed natural gas-fired peaker plants at six locations in New York City and one on Long Island. They operate infrequently — roughly 10 percent of the time, in recent years, when directed to do so to meet energy demands — providing local reliability and resiliency.

The study’s analysis is focused solely on NYPA’s in-city peaker plants.

 The following is a summary of the study’s key findings:

The findings of the study are dependent on production cost modelling assumptions, such as the future build-out and integration of more renewable resources and future transmission and distribution development and modernization.

While the study results indicate the potential of energy storage, the same results, also indicate that beyond 2030, as more electrification drives an increase in electricity demand, the system-wide energy need during periods of low renewable output will require perfect capacity (on-demand, reliable, and without duration constraints) energy resources or longer duration storage technologies to fill the gap and avoid reliability issues.

NYPA said it will be moving forward towards decarbonization through the implementation of several actions including the RFP’s issuance for the development of bulk-scale battery storage projects. Bids are due May 24, 2022, with potential awards announced July 1, 2022.  For more information on the RFP go to  NYPA’s Procurement website. 

In addition, NYPA will:

The study, conducted by Energy and Environmental Economics, Inc. (E3) and General Electric Energy Consulting, was commissioned by NYPA in consultation with the PEAK Coalition, and was supported by Strategen Consulting, as part of an agreement signed in 2020 between the two groups to assess how NYPA could transition its natural gas fired small clean power plants to use clean energy technologies, such as battery storage and low to zero carbon emission resources and technologies, while continuing to meet the unique electricity reliability and resiliency requirements of New York City.

The study is available here.  

The American Public Power Association’s Public Power Energy Tracker is a resource for association members that summarizes public power energy storage projects that are currently online. The tracker is available here.

Salt River Project To Study Low-Carbon Replacement Options For Coal-Fired Plant

May 3, 2022

by Paul Ciampoli
APPA News Director
May 3, 2022

With the coal-fired Coronado Generating Station (CGS) scheduled to close no later than 2032, Arizona’s Salt River Project (SRP) is launching several studies, and working with the local St. Johns community, to investigate possible low- or no-carbon reuses of the plant site.

CGS has a capacity of 773 megawatts (MW), from one 389 MW-unit and one 384 MW-unit.

SRP’s Coal Communities Transition Team has already begun work on a community engagement plan in coordination with the CGS community which consists of four stages, including conducting preliminary assessments of the community, developing economic and workforce plans, executing on the plans and determining post-plant support.

The initial studies into potential sustainable energy options at CGS will help SRP determine what, if any, technologies are viable. Some of the technologies that SRP anticipates researching could include hydrogen generation, solar with battery storage or other storage variations.

In addition, the City of St. Johns, Ariz., has shown an interest in studying the feasibility of transitioning CGS from coal to advanced reactor generation.

Leading these study efforts will be Gateway for Accelerated Innovation in Nuclear (GAIN), a U.S. Department of Energy initiative led by Idaho National Laboratory (INL).

SRP will coordinate with GAIN, which will work with experts at INL and other national laboratories to determine whether advanced nuclear reactors would be feasible at CGS. The findings will be a part of SRP’s study to evaluate options at the site.

The deployment of this technology, if proven viable, would likely have a long-time horizon of 20 to 30 years.

In the years leading up to the full operational shutdown of CGS in 2032, as well as in the years following, SRP will continue engaging with St. Johns and Apache County stakeholders and keep them informed of the results of these studies as they become available, SRP said on April 26.

Washington State Governor Tours Seattle City Light Microgrid Site

May 3, 2022

by Paul Ciampoli
APPA News Director
May 3, 2022

Washington State Gov. Jay Inslee and Seattle Mayor Bruce Harrell recently toured Seattle City Light’s recently completed Miller Community Center Microgrid.

They were guided on the tour by Seattle City Light Energy Innovation and Resources Officer Emeka Anywanwu. 

The tour included a stop inside the center to discuss its importance to the neighborhood and view the artwork installed as part of the project. The group then moved outdoors to the secured area that houses the microgrid control system and battery storage for an in-depth look at the technology behind the project.

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Seattle City Light Energy Innovation and Resources Officer Emeka Anywanwu provides tour
to Governor Jay Inslee of microgrid (photo courtesy of Seattle City Light)

The project is a collaborative effort between Seattle City Light and Seattle Parks and Recreation. It was funded in part by a $1.5 million Clean Energy Fund grant from the Washington State Department of Commerce.

The Miller Community Center microgrid brings higher power reliability to the surrounding community by keeping the facility energized during a power outage. It also helps to meet the City of Seattle’s goals by reducing greenhouse gas emissions through renewable (solar) energy and enhances the resiliency of Seattle’s electricity grid.

The project includes the installation of 132 solar panels on the Miller Community Center’s roof, which send energy to a battery storage system. This system provides backup power storage for the community center during emergency events, such as a windstorm or unplanned power outage.

When the electric grid is down, the microgrid generates and supplies power to the community center to keep the center’s services and communications operational. Other energy conservation measures included in the project were improved LED lighting, sensors, and an energy-efficient boiler.

The microgrid’s battery storage system has a total capacity of 200 kilowatts/ 800 kilowatt hours to provide at least 16 hours of backup power for 100% of the loads at Miller Community Center when fully charged. City Light expects the batteries to provide at least 24 hours of power during an outage. Additional power can be captured as the panels will continue generating energy when the sun is up.

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Seattle City Light General Manager and CEO Debra Smith speaks at event (photo courtesy of Seattle City Light)

Included in the project was a new interior art piece installed through a partnership with the Seattle Office of Arts & Culture and City Light’s 1% for Art Fund. Artist Julia Harrison commissioned the piece with input from the Miller Park community. The artwork combines and celebrates solar energy and community.

Texas City Says Its City Government Is First In The Nation To Mine Bitcoin

May 3, 2022

by Paul Ciampoli
APPA News Director
May 3, 2022

Fort Worth, Texas, on April 26 said it became the first city government in the U.S. to mine Bitcoin.

The pilot program, launched by the Office of Fort Worth Mayor Mattie Parker and the City of Fort Worth in partnership with Texas Blockchain Council, “recognizes the exponential growth of the blockchain and cryptocurrency industries while advancing Fort Worth’s goal of becoming a leading center of tech and innovation,” the city said in a news release.

The Bitcoin mining machines will run 24/7 in a climate-controlled data center located at Fort Worth City Hall, where they will be housed on a private network to minimize security risk, the city said.

Bitcoin mining is the process by which new bitcoins are entered into circulation. “Mining” is performed using sophisticated hardware that solves an extremely complex computational math problem. The first computer to find the solution to the problem receives the next block of bitcoins and the process begins again.

By limiting the pilot program’s focus to three machines, the city said it will achieve the goals of responsibly assessing and executing a municipal Bitcoin mining program at a manageable scale. After six months, the city will evaluate the program.

Based on the number and type of machines being used, the city estimates each will consume the same amount of energy as a household vacuum cleaner.

The nominal amount of energy needed for the program is expected to be offset by the value of Bitcoin mined. Keeping the pilot program small enables the city to learn the potential impact and opportunities for Bitcoin.

The City of Chandler, Ariz., recently began offering cryptocurrency as a payment option for Chandler residents to pay their utility bills.

Berkeley Lab Report Examines Growth Of Hybrid Power Plants

May 3, 2022

by Peter Maloney
APPA News
May 3, 2022

Generation projects that combine solar or wind generation with energy storage are poised to grow exponentially, but the success of those projects will require careful attention to factors such as project configuration and operational strategy, according to a new report from Lawrence Berkeley National Laboratory (LBNL).

At the end of 2021, there were more than 8,000 megawatts (MW) of wind or solar generation connected to storage in the United States, but a much larger number of hybrid projects — 280,000 MW of solar and 208,000 MW of storage – have applied for grid connections, the report, Batteries Included: Top 10 Findings from Berkeley Lab Research on the Growth of Hybrid Power Plants in the United States, said. The report noted that most of the proposals pair energy storage with solar photovoltaic projects.

Even if only a quarter of those projects are able to progress to commercial operation, “they will have big impacts on grid operations,” the authors of the report said in a statement. “While hybridization helps to ease the challenge of balancing variable supply and demand, its relative novelty means that research is needed to facilitate integration and promote innovation.”

In the new report, LBNL summarizes articles it published over the past two years in support of private- and public-sector decision-making about hybrid plants and presents its top ten findings.

Among the findings, LBNL noted that the growth in hybrid projects is being driven by a combination of factors, most notably falling prices and the incentives and synergies of co-locating energy storage with variable generation projects.

The report noted that power purchase agreement prices have fallen from $40-$95 per megawatt hour-photovoltaic (MWh-PV) in 2017 to $30-$75 per MWh-PV in 2021, and while the cost of adding storage to a solar project is around $10/MWh-PV for a battery sized to 50 percent of a project’s solar power capacity, the combination yields gains between $8/MWh-PV and $21/MWh-PV, depending on region and dispatch assumptions.

The authors also noted that hybrid projects can benefit from tax credits, construction cost savings, and more flexible generator dispatch, but suffer from siting constraints that make them “sensitive to local market conditions and configuration choices.”

For instance, LBNL found that, in some instances, the capacity contribution of hybrid plant is “less than the sum of its parts,” as the shared infrastructure of a hybrid project can reduce its capacity value.

Likewise, while hybrid plants can gain value from participation in ancillary service markets, at least in some markets, that value can be “fleeting” because those markets are thin and could become saturated by energy storage projects already in the interconnection queue. Expecting additional ancillary service revenues to offset declining energy and capacity value “may be a risky strategy for wind and solar hybrid project owners,” the report said.

Overall, “while hybridization of power plants provides opportunities to ease the challenge of balancing intermittent renewable resources, its relative novelty means that research is needed to facilitate integration and promote innovation,” the report’s authors said.

LBNL has scheduled a free webinar on May 5 for a closer look at its findings.

House Bill Aims To Address Increasing Electricity Demand Of EV Charging Infrastructure

May 3, 2022

by Paul Ciampoli
APPA News Director
May 3, 2022

U.S. Representatives Sean Casten, D-Ill., and Paul Tonko, D-N.Y., recently introduced the Electric Vehicle Grid Readiness, Improvement, and Development Act (EV GRID Act) to meet the increasing electricity demand of electric vehicle charging infrastructure.

The $7.5 billion for EV charging infrastructure in the Infrastructure Investment and Jobs Act was “a major step for EV investments and grid preparedness, but significant questions remain unanswered on how to ensure chargers can be interconnected with the grid,” Casten’s office said in a news release, noting that, for example, a Level 3 charger needs 350-kilowatts of electricity, “and in rural areas this would be a huge undertaking.”

The EV Grid Act would direct the Department of Energy to conduct a study and develop a plan related to the ability of the electric system to meet the electricity demand of new electric vehicle charging infrastructure.

The study would anticipate the growth in the use of electric vehicles necessary to meet President Biden’s climate goals, and would assess how much additional electrical generation, transmission, and distribution capacity will need to be added to the electric system to meet demand.

Through assessing various demand scenarios, DOE would then identify geographic areas in which greater investment in the electric system would be necessary to ensure chargers could be prevalent and connected to the grid.

After the study is published, the DOE would then work in coordination with the Building a Better Grid Initiative of the Office of Electricity and the Vehicle Technologies Office of the Office of Energy Efficiency and Renewable Technology to develop a plan on how DOE can assist the electric system in meeting the anticipated increase in demand. Congress would then be provided with recommendations on how these goals can be supported legislatively.

Tonko is Chair of the House Energy and Commerce Subcommittee on Environment and Climate Change.

Click here for resources and opportunities for public power tied to the infrastructure law curated by the American Public Power Association.

TVA, Canada’s Ontario Power Generation Partner On Small Modular Reactors

May 2, 2022

by Paul Ciampoli
APPA News Director
May 2, 2022

Canada’s Ontario Power Generation (OPG) and the Tennessee Valley Authority (TVA) will jointly work to help develop small modular reactors (SMRs), TVA recently announced.

The agreement allows TVA and OPG to coordinate their explorations into the design, licensing, construction and operation of small modular reactors.

Both are also actively exploring SMR technologies. OPG is moving forward with plans to deploy an SMR at its Darlington nuclear facility in Clarington, Ontario. The Darlington site is the only location in Canada licensed for new nuclear with a completed and accepted Environmental Assessment.

TVA currently holds the only Nuclear Regulatory Commission Early Site Permit in the U.S. for small modular reactor deployment at its Clinch River site near Oak Ridge, Tenn.

No exchange of funding is involved. However, the collaboration agreement will help OPG and TVA reduce the financial risk that comes from development of innovative technology, as well as future deployment costs.

Other Public Power Utilities Also Pursuing SMRs

Carbon Free Power Project, LLC (CFPP), a wholly owned subsidiary of Utah Associated Municipal Power Systems, continues to advance the development and deployment of its first-of-a-kind SMR nuclear plant at the U.S. Department of Energy’s Idaho National Laboratory near Idaho Falls, Idaho. 

CFPP successfully and safely completed field investigation activities at the site in January 2022, a major milestone for the project.  

In May 2021, NuScale Power and Washington State’s Grant County Public Utility District on May 26 announced the signing of a memorandum of understanding to evaluate the deployment of NuScale’s SMR technology in Central Washington State.

Public Power Utilities Well Positioned To Weather Cyberattacks: Fitch Ratings

May 2, 2022

by Paul Ciampoli
APPA News Director
May 2, 2022

Public power utilities are well positioned to weather cyberattacks “due to the electric sector’s years of attention to cyber threat mitigation and regulatory requirements, which offers a heightened level of protection relative to other infrastructure assets,” Fitch Ratings recently said.

The rating agency on April 21 noted that federal warnings of cyberattacks targeting U.S. critical infrastructure coincide with news reports of probing of the Texas energy infrastructure, which can be used to scan and monitor networks for weaknesses. “Risks are amplified, and increased information technology investment and spending will be necessary,” Fitch said.

The rating agency noted that the Department of Energy (DOE), Cybersecurity and Infrastructure Security Agency, National Security Agency, and the FBI jointly released an alert in mid-April to warn that certain advanced persistent threat actors are capable of gaining full system access to multiple industrial control systems (ICS) and supervisory control and data acquisition (SCADA) devices using custom-made tools that target ICS/SCADA.

“Electric utilities are exposed to these threats as they use ICS to connect into the electric grid and SCADA to gather and process data from substations. Events caused by operating technology (OT) breaches can threaten human safety and the availability of essential assets and are much more severe than IT breaches,” Fitch said.

The costs to maintain and update cybersecurity will rapidly increase to keep pace with elevated ICS threats amid geopolitical tension, the rating agency said. “System lifecycles are decreasing along with rapid evolution of technology and sophistication of cyber intrusions. Strengthening of cyber hygiene culture through investment in human capital and technology is critical to continue effective mitigation of fast-evolving” threats from advanced persistent threat actors.

Fitch also said that electric utility critical assets have been hardened by over a decade of compliance with the North American Electric Reliability Corporation’s critical infrastructure protection mandatory cyber security standards.

Moreover, the renewed emphasis on partnerships as threats increase “is supported by platforms allowing utility operators to share cyber threats in real time without compromising competitive or sensitive information,” Fitch said.

Public power groups such as the American Public Power Association and the Large Public Power Council provide their members with cybersecurity support programs, the rating agency noted, and CISA and the FBI updated the CISA Shields Up program in March 2022, providing best practices, technical guidance, free tools and resources that are available to all organizations.

APPA is helping member utilities across the country create a more resilient and secure electric grid that is prepared for both cyber and physical threats. Public power utilities are working with their communities, states, and the federal government to ensure compliance with stringent security standards and to manage risk. For additional details on how APPA is helping members with cybersecurity, click here.

Fitch said that the ability to protect infrastructure from attacks is considered under Fitch’s U.S. public power rating criteria as part of its assessment of management quality and governance, which is an asymmetric credit factor where weaker characteristics may constrain a rating.

Fitch assesses utilities’ cyber security policies, investment and training, their maintenance of insurance against cyberattacks and their protocols to address cyber incidents.

“No public power ratings are currently constrained by concerns regarding a utility management’s lack of preparation. In the event of a cyberattack, Fitch would assess the effect on financial metrics and performance of halts in service, delays in revenue generation, ransomware payments or unexpected capital costs,” the rating agency said.