Seattle City Light To Work On Project Focused On Grid-Interactive Efficient Buildings

November 9, 2021

by Paul Ciampoli
APPA News Director
November 9, 2021

Washington State public power utility Seattle City Light will work with the Electric Power Research Institute (EPRI) and the utility’s affordable housing provider partner, Community Roots Housing, to transform multifamily buildings in multifamily disadvantaged communities into grid-interactive efficient buildings (GEBs) with funding provided by the U.S. Department of Energy (DOE).

Background

In October 2021, the DOE awarded $61 million from its Connected Communities funding opportunity announcement for 10 projects that will demonstrate how energy efficient and grid-interactive technologies can transform homes and workplaces into connected communities.

DOE notes that America’s 129 million buildings use 40% of the nation’s energy and 75% of its electricity, which contributes to 35% of the nation’s annual carbon emissions.

As renewable power joins the grid at a record pace and buildings become more energy efficient, those emissions fall, but the variability of renewable power requires grid operators to employ new approaches to manage balancing electricity demand with variable renewable supply, DOE said.

It said that connected communities of grid-interactive efficient buildings (GEBs) integrate with distributed energy resources and leverage the greatest advancements in digital communications and building science by using smart controls, sensors, and analytics to “talk” to the grid, one another, and almost everything else that plugs into them.

Through advanced analytics, the comfort and needs of building occupants can be optimized while supporting grid needs so the amount of energy buildings require during the costliest periods of peak energy demand is reduced. This lowers utility bills and reduces grid system costs, DOE said.

Seattle City Light Will Work With EPRI, Affordable Housing Partner

Seattle City Light will be working with EPRI and its affordable housing provider partner, Community Roots Housing, to select buildings for the Connected Community demonstration. 

A variety of filters will be used in the selection process including building type, ownership, occupancy, housing-provider priorities, local grid and service characteristics, and others, noted Nathan MacDonald, senior public relations specialist at the Washington State public power utility.

“Internally we will be working with our Utility Technology, IT/OT, operations and planning staff to select an appropriate platform to use for DER interconnection and to determine use cases that we want to test.  We will also be coordinating with our program delivery staff for customer outreach and to provide incentives for eligible efficiency upgrades.” 

The first demonstration building will be operational by 2023, the second year of the grant. Performance data will be gathered and used in an energy model to determine the grid impact/benefit if the retrofit package were to be scaled across Seattle City Light’s service area. Based on these results, additional buildings will be selected for retrofit and final measurements and data will be collected to determine impact on the grid as well as the customer. “We will use the information collected and the evaluation results to develop future customer-facing utility programs as well as design of workforce development training, customer education and tech transfer,” MacDonald said.

“This will be a very holistic effort involving virtually all parts of the utility,” he said.

Next Steps

“Our very first next steps are to coordinate with EPRI and Community Roots Housing, the affordable housing provider associated with this proposal, to jointly determine the most appropriate buildings for the demonstration, both in terms of benefits to the occupants, the building owner and to the utility,” MacDonald noted. “The next level of benefit would be the learnings we can obtain for the buildings and selected technologies.”

Seattle City Light is also organizing internally to build a robust team to support this project in all the aspects, including customer support, cybersecurity, operations, planning, program design, data science and more. “A solid, engaged team is necessary for successfully completing this project and so far, everyone is excited to be part of this effort,” he noted.

The DOE grant has a five-year timeline, so the work will be completed by then. “However, we expect the first demonstration building to be operational by 2023, and further retrofits by 2025.”

In the early stages of the pandemic, Seattle City Light worked with Pacific Northwest National Labs and “embarked on an exercise we termed ‘Utility Next’ to develop 30% concept proposals in a wide range of topic areas to prepare for Federal and State stimulus money that could potentially be released to aid in economic recovery from the pandemic,” MacDonald noted. 

These topics ranged from EV charging to large scale solar, mobile power and fleet and building electrification.  Non-wires solutions and grid-interactive buildings was one of the topics included in this exercise and provided a solid base and head when the DOE Connected Communities grant was announced.  

“We were able to build on the work and thought process accomplished during the Utility Next program to start developing proposals for the grant application. Even prior to this Utility Next effort City Light has been interested in and worked with regional leaders to explore load-flexibility and grid-interactivity to most efficiently utilize grid assets as buildings and transportation are electrified,” MacDonald said.

Seattle City Light participated as an active stakeholder and partner in five separate proposals that were submitted for the DOE Connected Communities grant. “All the proposals were great projects and we would have been happy for any of them to win. That said, we are delighted to be working with EPRI on this proposal that prioritizes benefiting low-income housing and reducing the energy burden for disadvantaged populations, while also helping the utility explore non-wires solutions that can keep the cost of power low for all of our customers.”

Details on the other connected communities projects that received DOE funding are available here.

Fayetteville PWC Completes $94 Million Bond Issuance, Secures Historic Low Interest Rate

November 9, 2021

by Paul Ciampoli
APPA News Director
November 9, 2021

The Fayetteville Public Works Commission (PWC) in North Carolina has issued $94.79 million of revenue bonds at an interest rate of 2.278%, the lowest rate ever achieved by PWC outside of state lending. 

Citigroup Global Markets Inc. was the successful purchaser of the bond series and the PWC funding closed on November 4, 2021, PWC reported on Nov. 5. 

PWC issued its Series 2021 Bonds to fund improvements to its electric, water and wastewater utilities, including $22 million to fund continued work to retrofit utilities in the City of Fayetteville’s Phase V annexation area.

“The low cost of borrowing helps PWC maintain highly-reliable utility services and demonstrates the strength of Fayetteville’s utility system and its management,” said PWC CEO and General Manager Elaina Ball in a statement. “When we can fund continued system improvements through low-cost borrowing, it ensures we can continue to provide reliable utility services while also managing our customers’ costs.“

The bonds represent PWC’s continued investment in its electric, water and wastewater systems to support growth, reliability, water quality and compliance, Ball noted. “The investment continues to address PWC’s multi-year plan of rehabilitation and replacement of aging infrastructure to ensure safe and reliable services for our 118,000 customers,” she said.

Overall, $90 million of the bond funding is dedicated to PWC’s water and wastewater system. 

PWC will use $48 million to replace, upgrade and rehabilitate system mains, manholes and lift stations throughout its more than 2,500 miles of water and sanitary sewer system.  

Over $10 million will fund back up generation at PWC’s water and wastewater treatment facilities for storm readiness. Backup generators have been critical when hurricanes caused extended power outages and flooding. PWC’s Rockfish Water Reclamation facility will receive $8.2 million to fund plant improvements and expansion plans in support of community growth, it noted.

The PWC Electric system will use over $7 million of the bond funds to replace one of PWC’s 30 electric substations and fund the expansion of PWC’s battery storage system at its community solar farm by 1.5 megawatts. 

“PWC received favorable bond ratings by all three rating agencies which underpins our credit-worthiness and keeps our cost of capital low,” said Ball.   

“Utilities required a substantial amount of capital to keep up with growth, replace aging infrastructure and maintain the reliability of their systems. Having such a low cost of borrowing is a key benefit of being a publicly owned utility and helps manage bill affordability for our community,” she noted.

Moody’s, Standard & Poor’s (S&P) and Fitch Rating agencies all affirmed PWC’s AA stable financial ratings during the bond issuance process. 

Moody’s assigned PWC an Aa2 rating in a statement that noted PWC’s financial position will remain sound given its long-standing history of conservative budgetary practices and asset management.

Fitch Ratings assigned and affirmed PWC’s “AA” rating based on PWC’s very strong financial performance characterized by very low leverage, strong operating cash flow and healthy liquidity.

S&P assigned PWC its “AA” long-term rating stating key factors supporting the ratings include PWC’s deep and diverse service area, credit supportive policies and robust financial metrics. 

S&P said PWC has “a very strong operational and management assessment, highlighted by an experienced a sophisticated management team engaged in credit-supportive planning and in adopting a robust set of financial policies and reserves. “

PWC noted that the bond issuance process required significant resources working collaboratively over a well-designed and managed schedule spanning four months.

Chelan PUD’s Steve Wright Recognized As Longtime Champion Of Energy Efficiency

November 9, 2021

by Paul Ciampoli
APPA News Director
November 9, 2021

Chelan County PUD General Manager Steve Wright was recently honored with the Charles H. Percy Award for Public Service by the Alliance to Save Energy, a national nonprofit. The award recognizes Wright’s 40-year career as a champion of energy efficiency.

“The Pacific Northwest has made a wholly disproportionate contribution to national and global progress on energy efficiency, and Steve Wright is a huge part of the reason, starting with his adept, unflagging and inspirational leadership at the Bonneville Power Administration,” said Ralph Cavanagh, the energy program co-director of the Natural Resources Defense Council.

Wright served for 32 years at Bonneville Power Administration, including 12 years as administrator. During his tenure, he oversaw substantial increases in energy efficiency investments.

When Wright arrived as Washington State-based Chelan PUD’s general manager in 2013, he challenged the PUD’s energy efficiency team to double their energy savings goals. Over time, Chelan PUD met that challenge with a variety of customer-focused programs, including a partnership with local governments to help save money and save energy with facility upgrades, the PUD noted.

In April 2021, the PUD reported that Wright plans to step down from his position as general manager of Chelan PUD.

Wright currently serves as a member of the American Public Power Association’s Board of Directors and the board’s executive committee.

The PUD is headquartered in Wenatchee, Wash.

House Passes Infrastructure Bill That Includes Funding Opportunities For Public Power

November 8, 2021

by Paul Ciampoli
APPA News Director
November 8, 2021

The House of Representatives on Nov. 5 voted 228 to 206 to pass H.R. 3684, the Infrastructure Investment and Jobs Act, that includes numerous funding opportunities for public power utilities that are supported by the American Public Power Association (APPA).

The Infrastructure Investment and Jobs Act is an infrastructure and surface transportation bill that includes $1.2 trillion in funding for transportation, energy, and water infrastructure.

Of the $1.2 trillion, $550 billion is new federal spending that was not previously authorized. This includes $7.5 billion in federal spending for electric and alternative fuel vehicle infrastructure, $65 billion for broadband infrastructure, $65 billion for electric and grid infrastructure, $7.5 billion for zero- and low-emission school buses and ferries, and $47.2 billion for resiliency, including cybersecurity.

APPA members can get additional details on grant availability by clicking here.

Build Back Better Act

Immediately following the vote on the infrastructure bill, the House on a 221 to 213 party line vote approved H. Res. 774, a rule for considering H.R. 5376, the Build Back Better Act. The House will now postpone further consideration of the Build Back Better Act until congressional budget scorekeepers can provide analysis of the full spending and revenue effects of the measure.

As it stands now, the House may still vote on the most recent version of the Build Back Better Act, or it may vote on some final agreement on the bill if such an agreement is reached.

APPA supports the expansion of energy tax credits to include public power utilities provided under the Build Back Better Act.

Enactment of those provisions would complete decades of work to obtain comparable incentives to those provided to for-profit electric utilities by current energy production and investment tax credits.

But given the additional time provided by the delay in consideration of the Build Back Better Act, APPA will continue to seek improvements to the bill.

This includes seeking to exclude municipal bond interest from a new proposed corporate alternative minimum tax, seeking reinstatement of bond modernization provisions approved by the House Ways and Means Committee and seeking access to a $9.7 billion Rural Utility Services renewable energy program.

Platte River Power Authority Uses Vehicles for Student Engagement, Community Outreach

November 8, 2021

by Peter Maloney
APPA News
November 8, 2021

Platte River Power Authority (PRPA) is using model car racing to speed up its community outreach efforts.

For the past couple of years, the Colorado public power utility has sponsored NoCo Time Trials, a program in which student teams compete to have the fastest solar and battery powered model cars. Winners have the opportunity to participate in statewide races sponsored by the National Renewable Energy Laboratory (NREL).

NREL has hosted the Junior Solar/Battery Middle School Car Competition in Golden, Colo., for the past 30 years.

The aims of the program are threefold. “It supports STEM [Science Technology Engineering and Mathematics] education while providing a line of sight for kids and their parents for careers in the utility industry, and it expands our brand beyond their four walls,” Steve Roalstad, communications and marketing manager at PRPA, said.

The program is open to middle school students in the PRPA communities of Estes Park, Fort Collins, Longmont and Loveland, and interest has been growing, despite disruptions caused by the COVID-19 pandemic.

The utility began the program in 2019. Thirty-five student teams from seven schools participated. The time trials were canceled in 2020 because of COVID-19, but PRPA nevertheless made grants to the schools that had signed up for the program. Ordinarily PRPA gives grants to the participating schools at the conclusion of the time trials to help support STEM education.

NREL canceled its program last year, but PRPA held its time trials although they were virtual. A total of 85 student teams from 10 schools participated. The event concluded on May 13 with a virtual awards ceremony for three middle school teams with winning solar and battery cars.

Under the program PRPA provides the teams with model car kits the students use to build solar and battery power cars. The kits are standardized, but with the aid of teacher coaches, the students tweak them and experiment with their cars in an effort to make them go faster.

There are a variety of things they have tried, Roalstad said. They can try to lighten the chassis or optimize the gearing. In one case, students used PopSockets used to support smart phones to adjust the solar panels to maximize exposure to sun, he said.

PRPA’s budget for the program is “a little north of $20,000 a year,” which includes grants to the participating schools and, mostly, the cost of purchasing the model car kits.

It is a “tremendous experience to see the problem solving skills the children employ,” Roalstad said. “Those are the kinds of attributes we are looking for in the future.”

And for the students, “it helps them to connect the dots to the kind of career they could have. It also connects the dots for the parents, as well.”

The use of solar and battery power also aligns the program with the direction the utility industry is going, Kendal Perez, communications and marketing specialist at PRPA, said. “We tell them that is also what we are working on. It is very impactful.”

Roalstad admits that PRPA also has a “selfish” reason for sponsoring the program. By the time the participating students get out of college or trade school, up to 50% of the utility work force will be ready to retire. “We are opening our recruiting now,” he said.

PRPA has reached out to NREL, and they are planning to host a state tournament next May, Perez said. So PRPA has reached out to the teachers in its territory to gauge the interest in the program next year, she said.

The event is memorable enough for the kids that teachers are asking if Platte River would consider doing it for high schools, Perez said. For now, the focus is on organizing an in-person event for middle school students next year at Platte River’s newly-constructed headquarters campus.

DOE Unveils Goal To Remove Gigatons Of Carbon Dioxide From Atmosphere

November 8, 2021

by Paul Ciampoli
APPA News Director
November 8, 2021

U.S. Secretary of Energy Jennifer Granholm on Nov. 5 announced the U.S. Department of Energy’s (DOE) new goal to remove gigatons of carbon dioxide (CO2) from the atmosphere and store it for less than $100/ton of net CO2-equivalent.

The “Carbon Negative Shot,” the third target within DOE’s Energy Earthshots Initiative, is the U.S. government’s first major effort in carbon dioxide removal, DOE said.

The Earthshots Initiative aims to accelerate breakthroughs of more abundant, affordable, and reliable clean energy solutions within the decade.

Carbon dioxide removal is defined as a wide array of approaches that capture CO2 directly from the atmosphere and durably store it in geological, bio-based, and ocean reservoirs or in value-added products to create negative emissions.

DOE said that nearly all climate and energy models that reach net-zero indicate the need for a near-term focus on CO2 removal development and deployment to achieve carbon neutrality by 2050. By midcentury, carbon dioxide removal will need to be deployed at the gigaton scale, according to DOE.

President Joseph Biden has set a goal of achieving net-zero greenhouse gas emissions by no later than 2050.

Carbon dioxide removal technology “still requires significant investments in research and development to create a cost-effective and economically viable technology that can be deployed at scale and in time to meet the urgent needs of the climate crisis,” it said.

DOE said four performance elements will define the technologies DOE will advance through Carbon Negative Shot:

• A reduced cost of carbon dioxide removal of less than $100/net metric ton CO2 equivalent for both capture and storage;
• A robust accounting of lifecycle emissions (i.e., ensures emissions created when running and building the removal technology are accounted for);
• High-quality, durable storage with costs demonstrated for monitoring, reporting and verification for at least 100 years; and
• Enables necessary gigaton-scale removal.

Additional information about the initiative is available here.

Other Earthshots Initiatitives

Other Earthshots Initiatives involve hydrogen and long duration energy storage.

In June 2021, DOE launched an effort to reduce the cost of clean hydrogen by 80% to $1 per kilogram in one decade.

The following month, Granholm announced DOE’s new goal to reduce the cost of grid-scale, long duration energy storage by 90% within the decade.

Groups Support NERC Proposed Revisions Submitted To FERC

November 8, 2021

by Paul Ciampoli
APPA News Director
November 8, 2021

The American Public Power Association (APPA), the Large Public Power Council (LPPC) and the Transmission Access Policy Study Group (TAPS) said in joint comments submitted to the Federal Energy Regulatory Commission (FERC) that several of the changes resulting from proposed rules of procedure (ROP) revisions would appropriately implement the North American Electric Reliability Corporation’s (NERC) risk-based Compliance Monitoring and Enforcement Program (CMEP).

The groups urged FERC to approve the proposed changes.

At issue are ROP revisions filed by NERC and its six regional entities. As NERC explains in its filing, the proposed revisions to the ROP are designed to enhance NERC’s risk-based approach to monitoring and enforcing compliance with the NERC reliability standards and to enhance the ROP to add clarity and simplify unduly burdensome administrative business practices.

APPA, LPPC and TAPS noted that they have long supported a risk-based approach to NERC’s compliance monitoring and enforcement program, and said the proposed revisions to the ROP are appropriately aimed at reducing unnecessary burdens on NERC and registered entities while enhancing the effectiveness of the risk-based compliance monitoring and enforcement program approach.

The ROP revisions included in the September 29, 2021 filing were informed by substantial industry input.

APPA, LPPC and TAPS submitted detailed comments on NERC’s initial draft ROP changes, expressing general support for improved risk-based compliance, while providing a number of proposed changes, clarifications, and questions.

“The Public Power Trade Associations appreciate NERC’s consideration of these comments, and the alterations made to the proposed ROP in response. While not incorporating every comment in full, NERC responded meaningfully to the issues raised by the Public Power Trade Associations,” APPA, LPPC and TAPS said.

Such collaboration ultimately enhances the compliance monitoring and enforcement program by minimizing disputes over the CMEP’s rules, and by fostering confidence that industry perspectives on risk-based compliance are being heard, the groups said.

They highlighted the change reflected in a revised ROP section that would grant the relevant Compliance Enforcement Authority discretion as to when to conduct compliance audits rather than requiring an audit every three years, regardless of reliability or security justification.

APPA, LPPC and TAPS endorsed this change as advancing the risk-based approach to the compliance monitoring and enforcement program “and we urge the Commission to accept NERC’s proposed ROP revisions on this issue.”

They also endorsed NERC’s proposed changes to the evidence retention period for compliance audits.

Consistent with the recommendations of NERC’s recently concluded Standards Efficiency Review initiative these revisions would ensure adequate evidence to support compliance reviews, while reducing registered entities’ administrative burden and costs, the groups said. The proposed evidence retention change, as well as the other ROP revisions included in the September 29 filing, should be approved, they added.

Ithaca, N.Y., Votes To Electrify And Decarbonize Building Stock

November 7, 2021

by Paul Ciampoli
APPA News Director
November 7, 2021

The City of Ithaca, N.Y., recently voted to electrify and decarbonize its building stock. The city’s contract with BlocPower, a New York-based climate tech startup focused on greening aging urban building, represents the first large-scale, city-wide electrification initiative in the U.S., and a major step forward in Ithaca’s plan to become carbon-neutral by 2030, BlocPower said.

Ithaca’s Common Council on Nov. 3 voted to empower Ithaca Mayor Svante Myrick to negotiate a contract with BlocPower, which the city’s Planning and Economic Development Committee unanimously approved to manage the project after ratifying the results from its Energy Efficiency Retrofitting and Thermal Load Electrification RFP on October 20.

Building electrification is a key part of Ithaca’s Green New Deal.

BlocPower’s proposal estimates that the installation of air source heat pumps paired with supporting energy efficiency upgrades and other building improvements will cut Ithaca’s 400,000 tons of carbon dioxide by 40% and create 400 new green economy construction, technology and management jobs.

At the same time, it will make financing green energy upgrades affordable by providing low-cost loans to building owners, which they will pay back through the significant energy cost savings received, according to BlocPower.

Additional information about BlocPower is available here.

APPA-Funded Logan City Light & Power Energy Storage Project Advances

November 5, 2021

by Paul Ciampoli
APPA News Director
November 5, 2021

Pine Gate Renewables on Nov. 3 said that it has won a competitive bid with Logan City Light & Power (LL&P) to build a stand-alone energy storage system in Logan, Utah.

In 2020, LL&P received a $125,000 grant from the American Public Power Association’s Demonstration of Energy & Efficiency Developments (DEED) program to help fund the project. 

Providing 0.125 megawatts/0.5 megawatt hours (MWh) of backup energy for the grid, the Battery Energy Storage System (BESS) will be designed and integrated with the city’s System Operational Control Center, which monitors the municipal electricity distribution system, power plants, power contracts and call center. 

It will also be able to accommodate the area’s wide range of changing seasonal temperatures and elevation in northern Utah. 

“The LL&P energy storage project is another example of how public power utilities are at the forefront of innovation,” said Michele Suddleson, Director of R&D Programs at APPA. “It is also illustrative of how the DEED program helps public power utilities to improve their operations and services through grant funding.”

The project will use the Eos Znyth Gen 2.3 battery and Nikola Power’s Intellect Plus Energy Management System.

The Eos system, a zinc hybrid battery, along with Nikola Power’s Intellect Plus Energy Management System, has the ability to charge and discharge energy on a predetermined schedule as needed to allow for demand charge reduction, provide backup power to critical loads and supply additional grid services to maintain reliable continuity of service for the residents of the community. 

The BESS dispatches power during peak demand hours and ultimately delivers cost savings to customers. 

Blue Ridge Power will conduct the engineering, procurement and construction for the project, which is expected to be operational by late 2022. 

Pine Gate has more 12 gigawatt hours of storage in development either as stand-alone or combined with solar projects across the country. Its most recent solar plus storage project was Grissom Solar in Enfield, N.C., which went online earlier this year and provides 10 MWh of energy storage. 

DEED members can access reports on this and other projects in the DEED research library. The library is key word and topic searchable.   

Quarterly reports keep DEED members up to date on current projects, such as Logan’s storage project, and once a project is completed, the results, lessons learned, and any resources created to assist other utilities in replicating a similar project are shared in the library.

APPA Storage Tracker

The American Public Power Association recently launched a Public Power Energy Tracker, which is a resource for association members that summarizes energy storage projects undertaken by members that are currently online. The tracker is available here.

NREL Study Compares Storage, Energy Efficiency Building Stock Benefits

November 4, 2021

by Peter Maloney
APPA News
November 4, 2021

Pairing energy efficiency, rather than energy storage, with a renewable energy portfolio is more cost effective at achieving 100 percent renewable power for the nation’s building stock, according to a new study from the National Renewable Energy Laboratory.

As more states, cities, and municipalities commit to reducing their environmental impact by shifting to 100 percent renewable energy sources, the dominant challenge will be the long-duration misalignment of supply and demand, Sammy Houssainy and William Livingood, the authors of the report, Optimal Strategies for a Cost-Effective and Reliable 100% Renewable Electrical Grid, argue.

While energy storage can address that misalignment, the report, published in the Journal of Renewable and Sustainable Energy, found that alternative and readily available solutions are more cost effective and should be considered first. “Minimizing long-duration storage is a key element in trying to achieve the target cost effectively,” Houssainy said in a statement.

Using a techno-economic analysis, the authors said they identified cost-optimal, region-dependent, supply-side, and demand-side strategies that reduce, and in some regions eliminate, the otherwise “substantial capacities and associated costs of long-duration energy storage.”

The supply-side strategies investigated included optimal mixes of renewable portfolios and oversized generation capacities. Demand-side strategies considered included building load flexibility and building energy efficiency investments.

The results, the author said, “reveal that building energy efficiency measures can reduce long-duration storage requirements at minimum total investment costs.”

Their analysis showed that a combination of optimally mixed renewable resources, oversized generation capacities, and building energy efficiency investments can eliminate the need for long-duration energy storage in some U.S. regions, the authors said. “This is particularly important given that most long-duration storage technologies are either geologically constrained or still underdeveloped,” they wrote.

The study analyzed prototype building models in climate zones represented by five cities – Tampa, Fla.; El Paso, Texas; New York, Denver, and International Falls, Minn. – and found that the optimum renewable mix generally favors higher wind power allocations in colder climates and higher solar photovoltaic allocations in hotter climates.

For example, the authors said, Tampa would generate all of its electricity from solar panels, while International Falls would receive 100 percent from wind turbines in order to have the least reliance on energy storage.

The report also modeled oversizing renewable generation sources as a means of reducing energy storage needs and found that it can reduce energy storage requirements by ensuring that loads are met during times of otherwise inadequate supply.

Even though oversizing may require curtailing excess power during periods of abundant supply, the authors said oversizing “can have substantial impacts on storage capacities, and in some cases potentially eliminating the need for storage.”

“Our results reveal that cost-optimal renewable production factor ranges from 1.4 to 3.2, and optimal energy efficiency penetrations range from 52% to 68% savings, depending on the climate region,” they wrote. “Therefore, the benefits of excess generation capacities and building energy efficiency measures are outweighed by their incremental investments.”