Dispatchable solar coming to Kaua’i

When we at pv magazine look at places that are pushing the limits of what solar can do, there is no place that we look to like Kaua’i.

Sure, there are small islands and off-grid facilities where all needs are met with solar and batteries, and there are larger regions (California comes to mind) that also integrate relatively high levels of solar on the grid. But for the combination of the portion of demand met with solar (nearly 23% in 2017) and the scale (562 square miles, 66,000 residents), there is no place that we know of that has pushed the envelope as much as Kaua’i.

That the island is doing this with no wind to balance out the daily and seasonal variations in solar output, and that it is isolated, with no electrical connection to other islands to import and export power, makes this feat even more impressive.

Earlier this week the utility cooperative on the island took another step towards harnessing even more renewable energy. Kaua’i Island Utility Cooperative (KIUC) has signed a contract to have engineering firm McMillen Jacobs to design, engineering and construct a new 25 MW pumped hydro facility on the island, with will be paired with a solar plant of unspecified capacity.

KIUC describes this as “dispatchable renewable energy”, and like the solar plus battery storage projects currently underway this project will be important for meeting demand after the sun sets, including peak evening demand driven by the island’s tourist economy.

The West Kaua’i Energy Project is expected to meet 15% of the island’s energy needs on its own, and combined with other projects underway should blow through KIUC’s goal to meet 70% of electric demand with renewables by 2030, and instead could enable 79.8% by 2025 – up from 42.6% in 2017 (with hydro and biomass included).

Environmental studies are currently in progress. After finalizing the project design, McMillen Jacobs expects to have completed 60% of the engineering work by mid-2019.