With climate a central issue in the 2020 Democratic primary, contenders are seizing every opportunity to one-up the clean energy bona fides of their fellow candidates.

That was certainly on display during the first round of Democratic debates when former Vice President Joe Biden pitched his clean energy plans by leaning on progress made during the Obama administration.

“In our administration,” Biden proclaimed onstage, “we built the largest wind farm in the world, the largest solar energy facility in the world.” 

Biden’s claims were true at one point, but no longer.

Both the 1-gigawatt Alta Wind project located in California’s Kern County (built in several phases) and First Solar’s 673-megawatt Desert Sunlight project outside California’s Joshua Tree National Park (also built in several phases) came online during the Obama-Biden administration.  

Each held the distinction of being largest in the world for a time, but they’ve since been overshadowed. The world’s largest solar project, a 1.1-gigawatt monster located in the United Arab Emirates, began operating in July. 

For the record — Joe, are you reading? — here are the five largest solar projects currently planned or operating in the U.S. (All project sizes listed in direct current, or DC.)

5. Alamo

Texas claims several spots on this list, starting with the 577-megawatt, multisite Alamo project in San Antonio.

South Korea's OCI dove into the U.S. market through Texas, long before it became the red-hot market it is today. OCI Solar Power developed the sites and brought them online in 2015 and 2016. It later sold several to Consolidated Edison Development, the renewables development and ownership subsidiary of utility Con Ed.

OCI attached a 1-megawatt energy storage system to one of the solar sites, which the developer said was designed to provide fast response in ERCOT's market.

4. Topaz

Like Texas, First Solar makes several appearances on the list, starting with the third-ranked project, the 668-megawatt Topaz Solar Farm in California.

Pacific Gas & Electric is the offtaker, and the utility's bankruptcy has raised questions about a number of major renewables projects, including Topaz. In January, ratings agencies dropped the project's credit rating due to its reliance on PG&E for revenues. Moody's returned the farm to a positive outlook after PG&E filed its reorganization plan. The utility has pledged to honor its renewables contracts.

3. Desert Sunlight

Despite years of successful operation, some drama has followed Desert Sunlight, the 673-megawatt First Solar project in California's Mojave Desert that takes the No. 2 spot. Joint owners include General Electric, NextEra Energy and Sumitomo of America.

In July 2015 the project's owners sued the Treasury Department over claims that the government wasn't making good on its payments to renewable energy projects owed to Desert Sunlight under the 2009 American Recovery and Reinvestment Act (the very law that compelled significant renewables development during the Obama-Biden years). The U.S. District Court in the District of Columbia dismissed the suit in March 2016.

More recently, with bankruptcy looming for offtaker PG&E, NextEra filed a petition with the Federal Energy Regulatory Commission asking the agency to order that the utility "may not abrogate, amend or reject in bankruptcy any of the rates, terms and conditions of its wholesale power-purchase agreements." In June, a bankruptcy judge ruled that FERC doesn't have jurisdiction over PG&E's power contracts. 

The project's owners will be hoping that PG&E stands behind its aforementioned pledge for its renewables contracts.

2. Misae 2

Texas has become a boomtown for utility-scale solar, and now lays claim to the largest U.S. project, this one still under development. The 692-megawatt Misae 2 project* should be operational in 2021.

LAE American Energy, a subsidiary of Argentina-based solar, wind and biomass developer Latinoamericana de Energía, co-developed Misae 2 with owner and Texas-based medical doctor Miguel Oneto. It's the second phase of Misae Solar Parks, two projects adding up to over 1 gigawatt. The first Misae project sold to investment firm Copenhagen Infrastructure Partners while Misae 2 went to an unnamed investor.

So far, Misae is LAE's only project in the U.S., but it's not a huge surprise that the company chose to base its U.S. operations in Texas. As GTM reported in July, solar has been gaining steam in Texas' historically wind-dominated market. What the state lacks in policy incentives (like an aggressive renewable portfolio standard), it makes up for with a business-friendly vibe and its energy-only market.

According to the most recent data from ERCOT, the state's grid operator, solar is dominating the Texas interconnection queue, accounting for more than 64 gigawatts of the 111 gigawatts of capacity under study.

1. Gemini

The approximately 896-megawatt (690-megawatt AC) Gemini solar project is the only one on the list that includes significant battery capacity, a trend that’s growing among large U.S. solar plants. This one is still under development, slated for completion in 2020.

Co-developer Quinbrook Infrastructure Partners said the addition of storage should undercut carbon emissions compared to traditional generation sources by more than 1.5 million tons every year. In June, NV Energy signed a 25-year power-purchase agreement for the project's power, part of the Berkshire Hathaway-owned utility's plans to add 1.2 gigawatts of solar and hundreds of megawatts of storage through 2023.

In April, Nevada passed legislation that mandates 50 percent renewable electricity by 2030. Gemini is located outside of Las Vegas and was co-developed by California-based Arevia Power.


While U.S. projects regularly topped the global size rankings earlier this decade, they've largely been eclipsed by gigantic solar installations in markets like China and the Middle East.

Colin Smith, a senior solar analyst at Wood Mackenzie Power & Renewables, said U.S. developers tend to seek out more modestly sized deals, in part because sinking a huge piece of land into one contract isn’t the most efficient way to build a project. 

“It’s a lot easier for developers to site a massive amount of land and carve out portions of it for a particular [power-purchase agreement] than it is to sign all of it at once,” he said.

“It’s not out of the question that we’ll see a 1-gigawatt project one of these days, but realistically it’s easier to do two 500-megawatt projects over the course of six months in order to get better pricing and better offtake agreements in place, and to develop a more diversified portfolio for the developer and the utility offtaker.”

Correction: this story originally stated that Misae 2 was planned in two phases. Misae 2 is actually the second phase of a larger development that encompasses over 1 gigawatt of projects. GTM has also clarified that Misae 1 is the portion of the larger develpment sold to Copenhagen Infrastructure Partners. The story has also been updated with information regarding Dr. Miguel Oneto, a co-developer and original owner of the Misae projects.

Correction: This article originally ranked Gemini fifth. It is slated to be the largest solar project in the U.S. once completed. 

Correction: This article originally stated Texas does not have an RPS. That statement has been clarified to say Texas does not have an aggressive RPS.