Once completed project could supply up to 8% of city’s annual energy needs
A city floating three-megawatt solar array project that will produce roughly 6.5 million kilo-watt hours — enough energy to supply 8% of Healdsburg’s annual energy needs — is nearing completion and will likely be up and running and energized by the end of this year.
“Discussions of the concept date as far back as 2010 but detailed planning started in 2017. As part of a larger statewide project through the Northern California Power Agency (NCPA), the City was able to revive the concept and turn it into the project that's being built today,” explained Terry Crowley, the city’s utilities director.
The project works through a power purchase agreement with solar developer White Pine Renewables. It will be built and financed in exchange for the city of Healdsburg paying a fixed energy price over the term of contract.
Crowley said compared to wholesale energy prices, this project is estimated to save $1 million over the 25-year term contract.
Having the developer fund the project allows the tax credits to lower the cost the city pays for the energy. If the city had funded the project it would have to front the cash as a non-taxed entity, and it wouldn’t have been able to take advantage of the tax incentives.
“Annually the three-megawatt solar array will produce roughly 6.5 million kilo-watt hours. That's enough energy to supply 8% of Healdsburg's annual energy needs … 8% is a good chunk of energy. We have some state regulations that we are trying to achieve. The state wants us to get up to 60% renewable energy by 2030 and so we are trying to get onto that pathway,” Crowley said.
He said the city will certainly need more renewable projects in order to get the city up to that 60% renewable energy mark.
“We’re right around 40%, but we certainly have a need for more contracts and projects that can help get us up to that 60%. This is a good step in the right direction,” Crowley said.
Crowley said construction of the solar array has been a well-coordinated, yet laborious task.
The final design will float roughly 11,600 solar panels on the city’s recycled water ponds at the wastewater treatment plant on Foreman Lane. To put the size of the project in perspective, the typical home usually only has 10 to 12 solar panels.
Once the panels are installed the energy is collected and stepped up in voltage to connect to the city’s power grid. The energy is then delivered to the city’s electric customers through high-voltage lines.
“We are working hard to have the project interconnected and generating by the end of the year,” Crowley said. “It is a difficult process and there is a lot of work that has to happen before the end of the year but we’re hoping to have a plan to at least interconnect it and have some of the power going back into the city. It may not be the full three megawatts, but we’re really hoping to have something connected and generated before the end of this year.”
He said around January and February crews will continue to connect additional strings of solar panels and increase the output of energy up to the three megawatts.
He added that the developer for the project has a good team of well-experienced staff. White Pine is the same developer that worked on constructing Windsor’s solar pond project.
“The actual contractors doing the work did the Windsor (solar) project, so they have that experience with the pontoons and getting it floating and connected. They’ve been a great group to work with,” Crowley said.
The Windsor project, which is a bit smaller than Healdsburg’s, is the town’s own internal energy load.
“They (the town of Windsor) don’t have their own publicly-owned utility so they are just looking to offset their own internal load, whereas with this project we are really looking to conserve (energy) in the entire community of Healdsburg, or at least provide some proportion of the entire city’s needs with this project,” Crowley said.
As Crowley mentioned earlier, the solar array project is part of the city’s efforts to reach the state’s goal of 60% renewable energy by the year 2030. To get closer to that goal the city utility department is looking at procuring a contract for solar energy from Southern California and they’re also looking into hydro-energy.
“We have another contract for two megawatts of solar in Lancaster in Southern California and that project will come online in 2022. And that will provide another 6% of the city’s energy load/energy needs, so that will bump our total renewables up by 14%,” Crowley said.
He said they are also looking at hydro-energy contracts for small hydro outlets in the Sierras.
“We need to find the right price and contract to get those established as well. Nothing has been firmed up or executed yet,” Crowley noted.
Besides creating more renewable energy for the city a secondary benefit of the project is the shading of the recycled water ponds.
During the summer months algae grows in the raised ponds, but the shade from the solar panels will significantly reduce algae growth, thus improving the quality of the water which will ultimately be used for irrigation.
With the completion of the solar project the city might also have the ability in the future to create its own microgrid, which may come in handy during a power shutoff or public safety power shut off.
“We do have the ability to do a microgrid. We would have to install a pretty large battery system to make that work, but that is one of the things we actually have on the horizon is that we can potentially use this as part of a microgrid four or five years down the road. That would help to provide some resiliency in case PG&E decided to shut off our transmitter,” Crowley said.
Even though the city has its own electric utility, its power comes from PG&E transmitters.