- The project has been built using GPTech’s Advanced Multiport Power System, a Hybrid Conversion Power Electronics together with Proprietary Supervision and Control Platform.
- The project plan consists of a PV-plus-Battery System achieving 28 MW coupled to a 100MWh Battery Energy Storage System.
- It is the largest hybrid solar-plus-storage projects in the USA with a DC-coupled Battery Energy Storage System (BESS).
- By 2045, the state of Hawaii intends to utilize 100% renewable energy.
The Advanced Multiport Power System, developed by GPTech, has been selected by AES Distributed Energy Inc. (AES DE), to be used in the largest DC-coupled solar-plus-storage utility power plant in the United States inaugurated the last 8th of January.
The 28 MW solar photovoltaic (PV) plant located on Kauai Island in Hawaii uses DC-coupling to incorporate 28 MW and a 100MWh five-hour duration in energy storage, based on lithium batteries. The stored energy, at the AES Lawai Solar Project, allows a total dispatching of the power generated by the PV plant, ensuring a consistent night-time power. As a result, the power plant is expected to deliver roughly 11% of Kaua‘i’s power, making the island more than 50% powered by renewables.
The combination of PV and Battery Sources, sharing DC Buses, and the MPPT Management Algorithms take real advantage of the coupling, with a more efficient operation compared to AC-coupled approaches. In addition, this solution allows to store energy that, otherwise, would be lost due to the inverter clipping.
This project reinforces our role as energy manager expert applied to distributed energy sources integration into high value applications. The AES Lawai Solar Project is a key milestone for GPTech and the solar industry, because the important involved players who has trusted on us and our solutions, taking into consideration the relevance and challenges of the project. Hybrid DC-Coupling entails higher complexity both in the engineering stage and in the energy integration into the grid.
Functionalities such as dispatch, frequency response and voltage regulation let us claim that the manageability of this clean-energy facility can be compared with traditional power plants. This milestone is the first chapter of a new paradigm in terms of a harmonic coexistence of sustainability and grid manageability-quality in islands, easing the understanding of the energy community.
The solution has been designed ad-hoc to solve these challenges, guaranteeing its suitability. The system has being developed to ensure the best performance avoiding the inherent difficulties of this configuration.
The facility will deliver roughly 11% of Kaua‘i’s power, making the island more than 50% powered by renewables; increasing the portion of renewables in its mix to 60%, saving 3.7 million gallons of fossil fuel usage per year
DC – Coupled Features
The GPTech Hybrid DC-Coupled solution for the AES project comprised eight Advanced Multi-Port Stations (AMPS) together with a Power Plant Controller to provide enhanced grid support functions such as Frequency Response, PV Ramp Rate Smoothing, Energy Shifting, and Peak Demand Support.
Each GPTech AMPS includes two 1.4 MW DC/DC bidirectional battery power converter for managing the energy storage that is directly coupled to the DC bus of two 1.4 MW DC/AC bidirectional solar inverter. The AC output of the Multiport is then connected to the grid through a 2.8 MVA transformer. Energy management for the solar plus storage system is performed dynamically by GPTech’s Supervisory and Control Platform.
For detailed information about the plant: