January 8, 2019
By 2045, the state of Hawaii intends to utilize 100% renewable energy. Today, it’s one step closer to that goal. Together with Kauaʻi Island Utility Cooperative (KIUC) we inaugurated the largest operational solar + storage project in the world — the Lāwa’i Solar and Energy Storage Project located on Kauaʻi’s south shore. One of the world’s first solar powered peaking plants, it began providing evening and morning renewable capacity from the sun to the grid in December 2018.
On its way to 100% renewables, Kaua’i has adopted one of the most admirable mandates of any municipality in the world — stipulating that 70% of energy be supplied by renewable sources by 2030. This promising goal will eliminate Kaua’i’s need for oil to run its peaker plants, a dependence that has strained the economy. Because fossil fuels must be shipped onto the island, Kaua’i faces some of the nation’s highest electricity prices.
All-told, the new system will help Kaua’i top 60% renewables in the next five years. In the process, it will remove the annual cost and environmental impact of 3.5 million gallons of oil. The plant also avoids fossil fuels and herbicides used in traditional maintenance with 300 sheep on site to manage vegetation in an environmentally-friendly way.
Three Vital Power Distribution Scenarios
The Kaua’i project supports three vital scenarios in power distribution.
- It allows for solar generation to supply the grid while charging the battery system.
- It dispatches power stored in the battery system to the grid during peak demand periods.
- It can dispatch solar and battery power simultaneously to answer spikes in demand in addition to supporting the grid through provision of ancillary services.
While many other systems coexist but are not tied together, this project fully integrates all the components into one system.
Consisting of 28 megawatt (MW) solar photovoltaic (PV) and a 100 MWh five-hour duration energy storage system, the project provides peak capacity from the sun and allows the island to power itself with clean, renewable energy more than half of the time at a fraction of the previous cost.
A New Model for Renewable Energy
In combining solar power with battery-based energy storage, we can harness a renewable and intermittent source of generation and convert it into safe, reliable and higher-quality power. This establishes a new model for renewable energy that we refer to as firm renewables.
Kaua’i plans additional PV peaker plants throughout the island as part of its overall renewables strategy. AES has been a power supplier to Hawaii for more than 25 years, and we expect this solution to serve other solar-saturated markets where it’s beneficial to time-shift most of the energy generated. Instead of simply augmenting traditional generation, solar + storage can sequentially replace it altogether.
With higher penetration of renewables in global power markets, we’ll soon see conditions like Hawaii in many other parts of the world including remote grids in Baja, CA, systems in Alaska, and mining applications in the deserts of Chile. Declining costs of solar and use cases of projects such as this one will make similar systems the smartest choice to leverage abundant energy from renewables, and you can expect AES to announce more projects later this year.