LIHUE — A solar farm that is slated to generate about 5 percent of the island’s energy is set to power up early this year, according to representatives from the Kauai Island Utility Cooperative.
“Once the SolarCity/Tesla project goes online in early 2017, it will bring us very close to our goal of 50 percent renewable, well ahead of the target year of 2023,” said David Bissell, KIUC president and CEO. “We’ve been successful in reducing our use of fossil fuels by a full one-third. That equates to using 10 million gallons of diesel less than we were using in 2008.”
The SolarCity solar farm, which consists of 55,000 solar panels, will have the capacity to generate up to 22,000 MWh of power to ratepayers, said KIUC spokesperson Beth Tokioka. That’s about 5 percent of the island’s total energy consumption.
The farm, located next to KIUC’s Kapaia power plant, will also bring increased reliability via battery storage that will be used to help stabilize the grid and provide backup when other generators have to shut down.
“With the SolarCity/Tesla solar and battery storage project, power would be produced during the day and stored in batteries to be used during KIUC’s peak in the evening hours, when there is no sunlight,” Bissell said.
“KIUC strongly believes that dispatchable solar projects such as this and pump storage hydro are ways for Kauai to cost effectively meet our renewable energy goals.”
Currently, 36 percent of the island’s power come from renewable energy sources: 8 percent from hydropower, 11 percent from biomass and 17 percent solar.
The remaining 64 percent of energy comes from the use of oil, Tokioka said.
“Ultimately, this project locks in energy pricing at about the same rate as today’s low oil price while providing the environmental benefits of burning about 1.5 million less gallons of oil,” Bissell said.
Though the island continues to be reliant on diesel generators when the sun goes down, Bissell said KIUC is able to reach close to 100 percent energy use on some days through renewable energy.
“On many sunny days, we are able to produce 90 percent or more of our power from our solar, hydro and biomass sources,” he said.
In the state, Kauai experienced the largest increase in clean energy use in 2015 by increasing its renewable energy portfolio standard from 17.5 percent in 2014 to 27.3 percent last year, according to the Department of Business, Economic Development and Tourism’s Hawaii State Energy Office’s 2016 Energy Resources Coordinator’s Annual Report.
Tokioka said 3,390 households, or 12 percent of KIUC’s residential customers, currently have solar installations.
As of December, ratepayers pay about 33 cents per kilowatt-hour.
KIUC has agreed to purchase power from the SolarCity/Tesla project at around 14 cents per kWh for a period of 20 years.
“KIUC is working on innovative ways to add renewable energy sources to our grid,” Bissell said. “In the past six years we’ve increased our renewable portfolio from 9 percent of our fuel mix to 36 percent.”
KIUC utilizes power from five hydroelectric facilities, for a total of roughly 10.3 megawatts, Bissell said. KIUC currently holds a revocable permit for the Waiahi hydropower facilities, and purchases power from third parties who operate the other four plants.
The co-op’s use of the upper and lower Waihi hydro plants is regulated by the state Department of Land and Natural Resources.
With hydropower, water is diverted from streams, used to power a turbine to produce power, then the water is returned to the stream.
“Hydroelectric power has been used to generate power for more than 100 years on Kauai and is considered a ‘firm’ source of renewable energy, meaning that as long as there is water flowing, it will keep producing power,” Bissell said.
The energy generated from hydropower powers 6,000 homes.
KIUC estimates the burning of 2.5 million gallons of oil is avoided annually by the use of hydro facilities on the Garden Isle.
“It is important to note that the hydro facilities and their associated ditch systems were originally built to support sugar plantation operations, and most continue to this day to benefit farmers throughout the island,” Bissell said.
Representatives from SolarCity declined comment for this story.