Projects

Sandia’s Photovoltaic (PV) core capabilities include field testing combined with indoor characterization and energy prediction systems modeling to optimize PV performance, reliability, and degradation. Commercial off-the-shelf and emerging technologies such as cell type, module composition and architectures, and balance of systems components are studied.

Sandia partners with national labs, universities, and utilities as a trusted member of the PV community.

PV Proving Grounds

The PV Proving Grounds, a Department of Energy (DOE) Core Capability, conducts short- to long-term field research to understand the functionality of PV systems under real-world environmental operating conditions. Short-term research focuses on validating technology improvements designed to increase solar energy harvest while long-term research is conducted to assess PV system reliability and validate computer models for predicting power generation. Researchers at Sandia and the National Renewable Energy Laboratory (NREL) design and install PV systems to meet these goals, often in direct partnership with PV module manufacturers or equipment providers. US companies benefit from this direct interaction with the National Labs, allowing them access to unique capabilities and expertise. The PV industry benefits from the publicly available of the PV Proving Ground. Beyond PV module manufacturers, beneficiaries include system designers, installers, investment bankers, public utilities and independent third-party test labs.

Contact:
Bruce King, Principal Investigator
Phone: (505)-284-6571
Email: bhking@sandia.gov

Project Partners:
National Renewable Energy Lab (NREL)
Florida Solar Energy Center (FSEC)
University of Nevada Las Vegas (UNLV)

PV Performance & Modeling

This core capability includes the development, implementation, and validation of new performance submodels in the areas of module thermal behavior, dynamic soiling, performance degradation and stakeholder engagement through the PV Performance Modeling Collaborative (PVPMC) and IEA PVPS Task 13. PVPMC brings together researchers from academia and industry to share the latest ideas on how to accurately model and predict the performance of PV systems in the field. The PVPMC has hosted 13 workshops in four countries, hosts a website (https://pvpmc.sandia.org), and offers open-source software to users worldwide.

To learn more, visit the PV Performance Modeling Collaborative website.

Contact:
Joshua S. Stein, PhD
Phone: 505-845-0936
Email: jsstein@sandia.gov

PV PACT: PV Perovskite Acceleration for Commercial Technologies (PACT)

The PACT center focuses on developing a fair and level playing field for the emerging perovskite PV industry by:

  • Developing, testing, and validating characterization protocols that can quantify module performance and accurately measure power loss and degradation.
  • Developing accelerated testing protocols that can predict and identify early failures (5-10 years) and degradation rates.
  • Monitoring outdoor performance from fielded perovskite PV prototype mini-modules and modules and developing energy yield models that can predict performance in different climates.
  • Offering start-up guidance and bankability services to US perovskite PV companies in order to help them scale up from R&D cells to high-volume module manufacturing.

Read the PV PACT Fact Sheet.

Visit the PV PACT: PV Perovskite Accelerator for Commercial Technologies Center.

Contact:
Joshua S. Stein, PhD
Phone: 505-845-0936
Email: jsstein@sandia.gov

DURAMAT

The DuraMAT Consortium brings together DOE national laboratories and university research capabilities with the photovoltaic (PV) and supply-chain industries in pursuit of improving module reliability and durability.

Contact:
Dr. Cliff Hansen, Principal Investigator
Phone: 505-284-16433152
Email: cwhanse@sandia.gov

Active DuraMAT Projects include:

  • DuraMat Fielded PV Materials Research: The rapid technical evolution and market expansion of PV modules creates uncertainty around long term materials durability. Sandia leverages outdoor facilities and expertise in PV systems research to conduct short to medium term materials weathering studies. These studies range from assessments of small materials coupons to full-size commercial modules. Past and present DuraMat research projects have investigated the effectiveness and durability of anti-soiling coatings, characterized experimental backsheets and studied the long-term reliability of full-size modules. Contact: Dr. Bruce King

  • Data Cleaning for Degradation Analysis: This project provides open-source code resources to automatically filter time-series irradiance and PV power data, and methods to automatically translate textual O&M records to time series indicators of PV system availability. Contact: Dr. Cliff Hansen

  • Analyzing Hail Impacts on PV Modules using Computational Simulation: Objectives from this project include utilizing experimentally validated simulation models to identify the PV design parameters most influential to mitigating hail damage, such as module glass thickness, encapsulant type, or cell type, among others. Information gained from this project may help to reduce LCOE by providing a more precise understanding of hail damage risk, allowing optimized module design, deployment, and insurance decisions. Contact: Dr. James Hartley

American-Made Challenge Solar Prize

The American-Made Challenge Solar Prize was established by The Department of Energy (DOE) to help fund projects that develop innovative solar solutions. The challenge provides the winning teams with monetary vouchers to use at the national laboratory of their choice. When chosen, Sandia contributes to this challenge by partnering with the prize entrepreneurs and teams and providing testing expertise, capabilities, and access to facilities. The Solar Prize is an excellent way for Sandia to assist small businesses with their growth of technology, while exposing Sandia researchers to the latest technological innovation. Since the competition began in 2018, Sandia has supported 15 companies, including eight semi-finalists and four of the six grand prize winners.

Contact:
Laurie Burnham, Principal Investigator
Phone: 505-845-7354
Email: lburnha@sandia.gov

PV Optimization at Northern Latitudes

With the rapid growth of solar across northern regions, the impact of snow shading on modules is a growing concern. Published estimates of energy losses attributable to snow range from 1 to 12 percent annually, with monthly losses as high as 100 percent, depending on location and weather conditions; in addition, snow creates excessive and uneven stress on modules, cells and systems, the long-term impact of which is unknown.

This project aims to increase solar performance in northern regions of the US by identifying the multiple contributors to snow losses; modifying predictive models to more accurately reflect those contributors; and proposing mitigation strategies that boost both performance and reliability. Ultimately, this project aims to further the adoption, integration and optimal operation of the nation’s solar resources.

Learn more about the impact of snow on PV performance on the Snow webpage.

Contact:
Laurie Burnham, Principal Investigator
Phone: 505-845-7354
Email: lburnha@sandia.gov

Project Partners:
Michigan Technical University
University of Alaska, Fairbanks
University of Michigan

Connector Reliability

Sandia National Laboratories, in partnership with the Electric Power Research Institute (EPRI) and National Renewable Energy Laboratory (NREL), are working to increase the robustness of the US solar infrastructure by identifying, quantifying and mitigating risks posed by improperly installed, mismatched and/or improperly designed and manufactured connectors. Connectors have historically been viewed as essential, but relatively uninteresting—components of a PV system with a functional role that has been overshadowed by the industry’s focus on module efficiency and lower manufacturing and installation costs. Yet defective and degraded connectors affect system performance in profound ways, from power losses to increased O&M needs, to catastrophic failure and fire. In addition,degrading and failed connectors raise the specter of higher insurance rates, levelized cost-of-energy (LCOE) increases, and decreased confidence in the reliability of solar-generated power. The data generated from this project will help drive the industry toward higher-quality connectors and improved installation practices, thus increasing the performance, reliability, safety and availability of the US solar infrastructure.

To learn more, visit the PV Connectors webpage.

Contact:
Laurie Burnham, Principal Investigator
Phone: 505-845-7354
Email: lburnha@sandia.gov

Photovoltaic Collaborative to Advance Multi-climate Performance and Energy Research (PV CAMPER)

The mission of the PV CAMPER project is to create a global technical platform that enables pioneering photovoltaic research, validates the performance of emerging technologies in specific climates and helps accelerate the world’s transition to a solar-intensive economy.

To learn more, visit the PV CAMPER webpage.

Contact:
Laurie Burnham, Principal Investigator
Phone: 505-845-7354
Email: lburnha@sandia.gov

Optimization of Single Axis Trackers

This project will optimize the performance of single axis solar trackers by improving the collection of solar radiation under cloudy or partly cloudy conditions. Project work will involve collecting sky imagery data at several locations around the US and using these data to inform optimized tracking algorithm development. Sandia is collaborating with Array Technologies, Inc. to develop the additional data sets, and begin the deployment of optimized tracking algorithms in small-scale field hardware. The project for the improvement of single axis tracking algorithms is funded by The Department of Energy’s Technology Commercialization Fund (TCF).

Contact:
Daniel Riley, Principal Investigator
Phone: 505-284-3152
Email: driley@sandia.gov

Performance and Reliability of Single-Axis Tracker (SAT) Systems

This project seeks to improve the performance and reliability of single-axis tracker (SAT) systems. The primary four thrust areas seek to 1) improve standards that govern solar trackers to increase their relevance to single axis solar trackers; 2) improve methods of detecting failure of SAT systems through data analytics and sensor deployment; 3) develop new modeling and simulation tools for fields of single-axis trackers including modeling near-field shading and horizon effects; and 4) develop of tracking optimization algorithms that utilize sky images to predict likely future events and plan tracking solutions based on those events. This project is funded through the Department of Energy’s Office of Energy Efficiency and Renewable Energy 2021 Laboratory Call.

Contact:
Daniel Riley, Principal Investigator
Phone: 505-284-3152
Email: driley@sandia.gov

Operations and Maintenance Challenges for PV + Storage

Sandia National Laboratories, in partnership with the National Renewable Energy Laboratory, is working to understand the drivers influencing the operations and maintenance (O&M) for PV+storage systems in the United States. This project uses a mixed methods approach, combining semi-structured interviews and data analysis to better understand how storage technologies were selected for PV facilitates, what O&M activities are being conducted, and what ongoing challenges and needs exist. Given the rapidly evolving practices within PV+storage, the findings are expected to provide valuable insights into common challenges as well as management of O&M for PV+storage.

Contact:
Nicole Jackson, Principal Investigator
Phone: 505-284-2346
Email: njacks@sandia.gov

Completing the Feedback Loop: Linking Data, Operations and Maintenance, Manufacturers, and Insurance Markets

Component manufacturers and plant operators in the PV industry are often motivated financially to focus on initial capital costs, rather than the levelized cost of electricity over the plant’s service life. Sandia National Laboratories, in partnership with kWh Analytics, the National Renewable Energy Laboratory, the Solar Energy Industries Association, and others, is supporting the analysis of operations and maintenance logs to identify top failure modes. These results will support solution development (e.g., prioritizing hardware solution and offering insurance discounts) to help improve solar manufacturing and financing.

Contact:
Thushara Gunda, Principal Investigator
Phone: 505-845-3440
Email: tgunda@sandia.gov

Quantifying Uncertainty in PV

In collaboration, Sandia National Laboratories and National Renewable Energy Laboratory are working to provide (1) standard definitions of uncertainty sources in PV modeling, (2) a computationally efficient framework for combining different sources of uncertainty, (3) a recommended practice to represent solar resource uncertainty in PV energy estimates, and (4) an open source implementation of new uncertainty methodologies in the System Advisor Model, and (5) a report documenting best practices for quantifying uncertainty in energy production estimates.

Contact:
Dr. Cliff Hansen, Principal Investigator
Phone: 505-284-16433152
Email: cwhanse@sandia.gov

Robust PV Performance Loss Rate Determination and Power Forecasting: Using Spatiotemporal Graph Neural Network Models in a Reliable System-Topology-Aware Learning Framework

This project uses artificial intelligence and machine learning techniques to analyze data from a large number of neighboring photovoltaic (PV) systems in order to extract information about their short- and long-term performance. Machine learning methods will be used to overcome data quality issues affecting individual plants. The development of spatiotemporal graph neural network models will address critical questions of long- and short-term performance for fleets of PV plants. The proposed learning techniques advance both analytical techniques for long-term performance of PV power plants and deep learning techniques, and can mitigate the negative impact of PV plant or sensor failure or unreliable input data.

Principal Investigator: Roger French, Case Western Reserve University, Email: roger.french@case.edu

Sandia Researcher: Jennifer Braid, jlbraid@sandia.gov

Industry Outreach

  • mPower: Sandia National Laboratories provided technical assistance to mPower under the New Mexico Small Business Assistance (NMSBA) Technology Readiness Gross Receipts (TRGR) program. mPower is a New Mexico company developing photovoltaic (PV) array technology for space applications. Sandia provided assistance in three areas: (1) perovskite PV and tandem cell characterization, (2) molecular dynamics simulations testing strategies to mitigate radiation defects in c-Si solar cells and (3) thermomechanical modeling of electric flex circuit designs for interconnecting solar cells into module and systems.
  • Toward Commercialization of Low-Cost, Crack-Tolerant, Screen-Printable Metallization by Full-Size Module Testing and Field Characterization: This project will develop a cost-effective metal paste that strengthens the metal connections in solar cells, improving their resistance to fracture, and minimizes cracks that result from degradation and handling. This will increase the long-term durability of the cells. The team will measure and compare crack tolerance with this paste compared with conventional metallization paste through module mechanical testing at Sandia National Laboratories. Principal Investigator: Sang Han, Osazda Energy, sang.m.han@osazda.com; Sandia Researcher: Jennifer Braid, jlbraid@sandia.gov
  • Affordable Solar: This project focuses on a calculator, which is used to determine the capacity of a specific photovoltaic (PV) system. Contact: Marios Theristis
  • GAF: Sandia is collaborating with GAF Energy to evaluate the performance and reliability of a novel PV module that incorporates PV cells directly into a traditional roof shingle. Sandia designed and constructed a fully instrumented test roof deck where the energy harvest of the PV shingles is continuously monitored. This data is analyzed to track reliability and is compared to the performance of conventional roof-mounted PV panels to inform financial models. Sandia is building an energy performance model for this building integrated product using characterization data from two-axis sun trackers and will validate the model against the data from the test roof deck. This collaboration is extended into a diverse set of climates through partnerships in Florida, Michigan and Colorado. Contact: Dr. Bruce King
  • Nishati: Nishati is developing a novel PV module package that is uniquely constructed of a polymeric matrix and a internal honeycomb structural element. Designed to be deployed around airports and air bases, the module features reduced glare from reflected sunlight – an ocular hazard for pilots – and reduced weight. In this ongoing collaboration, Sandia helped Nishati optimize the materials selected for module construction and validated the performance of full-size module prototypes. Currently, Sandia is conducting long-term outdoor evaluation of the reliability of the design. Contact: Dr. Bruce King
  • SunPower: SunPower and Sandia have collaborated for more than two decades, dating back to SunPower’s earliest days as PowerLight. This long-term collaboration has frequently involved optimization and validation of SunPower’s products and has given Sandia access to new PV technologies before they become available in the market. Current collaboration centers on performance and reliability of a novel module architecture featuring overlapping or “shingled” solar cells, which reduces internal resistance losses, increases PV active area and is more shade tolerant than conventional modules. This is a multi-climate study with systems installed in Nevada, Florida and Michigan. Contact: Dr. Bruce King