The Healdsburg California floating solar farm used pond space that wine country land could not spare
The Healdsburg California floating solar farm switched on in March 2021, and was named the largest floating solar installation in the country at the time by its developer and 2 news outlets that covered its debut. White Pine Renewables and Noria Energy built the 4.78 megawatt array across half of 2 treatment ponds, choosing water instead of land because almost all the land around Healdsburg grows wine grapes for the local wine industry. Terry Crowley, the utilities director for Healdsburg, explained why floating panels made sense there.
You couldn't go out and buy a bunch of vineyard land for a solar project and make it economical.
Terry Crowley, utilities director for Healdsburg. Source 2.
The floating array edged out the previous record by less than half a megawatt
The previous largest floating solar installation in the country was a 4.4 megawatt project in New Jersey, energized in late 2019. Healdsburg surpassed it by a narrow margin when its own array switched on a little over a year later. Jon Wank, chief executive of Noria Energy, described how fast the scale of these projects had grown in just 2 years.
When we started these two years ago 500 kilowatts would've been large.
Jon Wank, chief executive of Noria Energy. Source 2.
The New Jersey project held the record from late 2019 until Healdsburg switched on in March 2021.
Show the numbers
| New Jersey project, prior record, 2019 | 4.4 |
| Healdsburg California array, 2021 | 4.78 |
Crews built the array in about 4 months, partly to help Healdsburg recover from wildfires
Assembly began in mid October 2020 and the array was mostly complete by mid January 2021, a build of about 4 months. White Pine Renewables says on its own project page that the fast schedule was driven in part by the recovery of the city from wildfires that hit the region in 2020, a detail the news coverage of the debut did not mention. The finished array holds 11,600 double sided solar panels, catching sunlight from above and its reflection off the water below, and covers about half of the 2 ponds combined 15 acres.
The floating panels also protect the water Healdsburg later sends back to the vineyards
An Idaho National Laboratory and Pacific Northwest National Laboratory report for the United States Department of Energy studied the Healdsburg array as a case study, independent of either company own marketing. It found the floating panels reduce algae growth and evaporation in the treatment ponds themselves, which improves the quality of the treated water later used to irrigate the same vineyards whose land made the project too expensive to build on the ground in the first place.
The array supplies about 8% of Healdsburg electricity, and cost an estimated 9 million to 12 million dollars
Under a 25 year agreement, the array supplies about 8% of Healdsburg electricity demand, and 1 outlet estimated it generates enough power for roughly 1,120 households a year. With the array online, Crowley told reporters that 48% of Healdsburg electricity now comes from renewable sources, against a city target of 60% by 2025. City officials said they did not know the exact cost of the project, estimating it at 9 million to 12 million dollars.
City officials told reporters they did not know the exact cost of the project and gave this range as an estimate.
Show the numbers
| Healdsburg floating solar array | 9 million to 12 million dollars |