American-Made Challenges


Solar Prize Round 6

The Solar Prize Round 6 offers $4.1 million in cash prizes to competitors over three progressive contests.

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This challenge is closed



Solar Prize Contests

Innovation happens when the right resources, people, and passion come together. With the American-Made Solar Prize Round 6, teams of creative individuals and entrepreneurs advance conceptual solutions toward product realities with the support of a unique and powerful network and a chance to win part of $4.1 million in prizes.

A Prize Competition Structured for Success

The Solar Prize encourages the rapid development of innovative solar energy solutions capable of addressing the tough challenges facing the solar industry. Solar Prize competitors participate in three contests—the Ready!, Set!, and Go! Contests—to transform their ideas into reality in months, rather than years. Competitors have the chance to win part of $4.1 million in prizes to help them advance in the competition and accelerate the development of their solution.

Round 6 includes an optional additional challenge that focuses on advancing solar in underserved communities. Participants who choose to incorporate this initiative into their solutions have the chance to be considered for a new Justice, Equity, Diversity, and Inclusion (JEDI) Contest and a bonus cash prize!

More than $3 Million in Incentives for Innovation

The Ready!, Set!, and Go! Contests fast-track efforts to identify, develop, and test disruptive solutions to solar industry needs for a total of $3 million in cash prizes and $900,000 in vouchers that can be used at national laboratories and other voucher facilities to develop, test, and validate. Each contest has a performance period when participants work to advance their solutions.

The Ready!, Set!, and Go! Contests

  • Ready! Contest
    20 winners / $50,000 cash prize each and optional JEDI Contest prize
    Winners are selected after identifying an impactful idea or solution addressing a critical need in the solar industry;
  • Set! Contest
    10 winners / $100,000 cash prize each, $75,000 support voucher each, and optional JEDI Contest prize
    Competitors work to substantially advance their technology solution toward a viable and promising proof of concept.
  • Go! Contest
    2 winners / $500,000 cash prize each, $75,000 support voucher each, and optional JEDI Contest prize
    ​Competitors work to substantially advance their solution from proof of concept to a refined prototype and find a partner to perform a pilot test of the prototype.

Demo Days

During the competition, competitors in the Set! and Go! Contests pitch and demonstrate proofs of concept and prototypes to a judging panel and audience at two live, in-person Demo Day events. Demo Days are opportunities to meet competitors, Connectors, Power Connectors, and other members of the American-Made Network. Demo Days culminate in the announcement of Set! finalists and Go! winners.

Connecting You to the Innovation Engine 

The American-Made Network provides support to Solar Prize competitors throughout the competition and is comprised of national labs, incubators, investors, facilities, and seasoned industry mentors. The American-Made Network strengthens and scales the critical connections needed to grow new businesses, develop solutions, and sustain American innovation. Members of the Network provide the tools, technical insight, product validation, industry expertise, and strategic support teams need to succeed throughout the competition.

Anyone can Compete

Competitors are entrepreneurial individuals or teams, legally residing or based in the U.S., including members of one or multiple organizations, students, university faculty members, small business owners, researchers, or anyone with the desire and drive to transform ideas into impactful realities.

Here's how to join the Solar Prize Round 6:

  1. Identify an important problem you want to solve
  2. Submit a 90-second video describing your challenge and proposed solution, team, and plan
  3. Answer a short, four-question narrative and make a slide about this problem or challenge
  4. Submit a two-page technical assistance request
  5. Update your videos and statements as you advance through the contests.


Challenge Guidelines

Please review the official rules for the complete application process and instructions for competing.

If you want to receive updates on the prize or have any questions, please subscribe by using the contact feature on the HeroX platform or message us directly at .

The American-Made Solar Prize is a multimillion-dollar prize competition designed to energize U.S. solar innovation through a series of contests that accelerate the entrepreneurial process from years to months. The American-Made Solar Prize is directed and administered by the National Renewable Energy Laboratory and is funded by the U.S. Department of Energy Solar Energy Technologies Office. Learn more.


Challenge Updates

Winner Highlight: Latimer Controls

March 18, 2024, 9:45 a.m. PDT by NREL Prize Administrator

In September 2023, Latimer Controls was named a grand prize winner of the American-Made Solar Prize Round 6. But what’s next for the team and how has the Solar Prize impacted their trajectory? 

Latimer Controls received a total of $650,000 in cash prizes for their innovative solutions to speeding the transition to rapid and equitable solar energy deployment. They also received $150,000 in technical support vouchers to help them bring their concept to life.

Latimer’s winning technology is a software control solution that allows large solar operators to provide reliable and demand-ready power. The Latimer Flexible Solar Management System increases the flexibility of utility-scale solar photovoltaics by continuously reading in real-time the maximum grid power point, proactively curtailing generation, and ramping up generation as needed to meet power demand. This innovative solar solution improves the reliability and sustainability of large-scale solar on the grid. 

Latimer Controls originated in CEO Simon Julien’s graduate research at the University of Colorado-Boulder and graduate internship at the National Renewable Energy Laboratory. Over the next 3-6 months, Julien, along with co-founders Zachary Jacobs and Tristan Liu, will use their winnings to expand their team and implement their first pilot project. Latimer will partner with Kauai Island Utility in Hawaii to manage 24 MW of solar power.

See Latimer Controls’ winning Solar Prize submission and learn more about their startup!

Winner Highlight: ReJoule

March 4, 2024, 8:30 a.m. PST by NREL Prize Administrator

In September 2023, ReJoule was named a grand prize winner of the American-Made Solar Prize Round 6. But what’s next for the team and how has the Solar Prize impacted their trajectory?

ReJoule received more than $740,000 in total cash prizes for their innovative solutions to energy access and battery circularity. In addition to the cash prizes, ReJoule received $150,000 in technical support vouchers to use at national labs and other partnering facilities. ReJoule was also named the Justice, Equity, Diversity and Inclusion (JEDI) Contest winner for their focus on advancing solar in underserved communities.

ReJoule’s winning technology converts decommissioned electric vehicle (EV) batteries into solar storage that can be deployed in critical infrastructure. Their initial target market is critical infrastructure serving disadvantaged communities like affordable housing, homeless shelters, health clinics, and food banks. According to ReJoule, when EV batteries no longer offer the range required for the road, they can still retain about 80% of their original capacity. 

As contestants in the Solar Prize, ReJoule launched a pilot project with the California Botanic Garden to deploy used batteries from eight EV delivery trucks in a solar microgrid. The microgrid could save the Garden $35,000 a year in electricity costs and provide the local community with a cool zone to find relief when the larger power grid fails.

Siblings and co-founders Steven and Zora Chung launched ReJoule in 2017 as a battery diagnostics company, but the Solar Prize allowed them to expand their focus and explore new methods for using batteries to store solar power and dispatch it at peak hours and in emergency situations. With their winnings, ReJoule plans to expand their team and deploy solar with re-used batteries at two new pilot sites. 

See ReJoule’s winning Solar Prize submission and learn more about their startup!

$1.85M Digitizing Utilities Prize Round 2 Open Through May 7

Feb. 15, 2024, 11:24 a.m. PST by NREL Prize Administrator

Hey, competitors! Did you know the American-Made program is continuously launching new, exciting prizes that support a wide array of clean energy sources? In fact, the Digitizing Utilities Prize is back for Round 2 and searching for innovative solutions to some of the biggest challenges facing electric utilities across the U.S. 

 This two-phase, $1.85 million prize aims to connect utilities with interdisciplinary teams of software developers and data experts to transform digital systems and data analytics for utilities in the energy sector. This round will also address cybersecurity threats and risks with demonstrated improvements in risk identification, analysis, prediction, or proactive response for enhanced protection of digital energy infrastructures.

Register today for an informational webinar on March 21st at 12 p.m. ET to hear more about the competition, including deadlines, submission requirements, and other important prize details. (Can’t make the webinar? A recording of the event will be posted on the prize’s HeroX page within a few days of the event.) 

 We hope to see you at our March webinar! 

 -The Digitizing Utilities Prize Round 2 Admin Team

Congratulations to the Winners of the Solar Prize Round 6!

Sept. 13, 2023, 2:44 p.m. PDT by NREL Prize Administrator

Two more teams can add “Solar Prize Winner” to their accolades after pitching winning concepts and taking home cash prizes during Go! Demo Day on Sept. 12!

During this final contest of the prize, teams worked on developing and testing their product or prototype, building their network, and making a long-term plan for the success of their concept. The two teams who most successfully demonstrated their progress—and received $500,000 cash—are as follows:

  • ReJoule (Signal Hill, CA): This team is developing a fast, new method for testing the health of decommissioned electric vehicle (EV) batteries and using these batteries to develop an integrated solution for storing solar power and dispatching it at peak hours. This allows for fast screening of used batteries and certification for use in grid scale storage of solar energy.
  • Latimer Controls (Boulder, CO): This team is developing an intelligent control software that enables utility-scale PV to provide power reliably and on demand. This will replace grid reliance on fossil fuels, drive higher profitability for PV operators, and generate revenue increases for solar asset owners with low capital cost.

The teams also received $75,000 in technical support vouchers to help the team bring their concept to fruition. The pitch showcase and winner announcement took place during the RE+ Conference in Las Vegas.

In addition to the grand prize, ReJoule, was also awarded $50,000 for their winning submission to the Justice, Equity, Diversity, and Inclusion (JEDI) Contest, which focuses on advancing solar in underserved communities. They are the first Solar Prize team to win both the grand prize and the JEDI Contest prize. 

Congratulations to everyone who participated in Round 6 and contributed their innovative ideas for energizing solar innovation! Don’t forget, Round 7 is open and accepting submissions now through Sept. 27. We highly encourage Solar Prize newcomers and alumni to apply! 

Hear the Big Solar Prize Round 6 Winner Announcement Tonight!

Sept. 12, 2023, 1:15 a.m. PDT by NREL Prize Administrator

Tune in to our livestream tonight as the Solar Prize finalists compete for the grand prize at RE+, with two teams taking home $500,000 each! Plus, up to two teams can walk away with additional cash prizes in the optional Justice Equity, Diversity, and Inclusion (JEDI) Contest! 

If you’re at RE+, make sure you join the Solar Prize Round 6 Go! Demo Day, taking place today, Sept. 12, at 4 p.m. PT at the Innovation Stage. You’ll get a front row seat as the 10 finalists present their innovative technologies—then hear who takes home $500,000!

Not at the conference? Tune in to the American-Made Twitter account tonight for a livestream of the 2-hour event, including pitches, guest speakers, and the grand prize winner announcement. 

We hope you join us for this exciting event and find an opportunity to connect with the American-Made team during the conference. Good luck, finalists!