KIUC is now allowed to access the Puu Lua Reservoir and state land in order to undertake feasibility work, including cengineering and geotechnical studies.

The cooperative should also negotiate separate agreements with the state Agribusiness Development for the lease of land on the Mana Plain, where a lower storage pond would be constructed.

The 25MW project, which is expected to cost $55m to $65m, will address the need of how to capture cheap and excess solar energy generated during the day, store it, and then use it at night when demand for electricity is high.

It will utilize Puu Lua as an upper storage pond linked by a five-mile-long buried steel pipeline to a lower pond.

Upon its planned completion by 2019, the project will generate about 13% of the energy used on Kauai.

KIUC said the cost of energy produced by the system would be about 35% less than the cost of oil and once paid off.

The cooperative needs to secure an environmental assessment and a separate lease agreement for the water it will utilize.