In a field just off the beach on Grand Cayman, Trimark will deliver an advanced SCADA system to monitor and control the first, utility-scale photovoltaic (PV) power generation resource in this island nation.
The 5 MW electric power generation resource in Bodden Town, Grand Cayman, is being developed by Entropy Cayman Solar Limited. Entropy contracted Trimark to deliver T1-S SCADA, an advanced PV plant control/SCADA system that will support operations, regulate electric power generation and stabilize power at the point of interconnection with the Caribbean Utilities Company’s (CUC) electric grid.
The system includes weather and solar irradiance sensors that are required to calculate plant efficiency and determine maintenance intervals. In addition to the SCADA system, Trimark will provide a revenue-grade meter to measure power delivery and other values.
Because the site is so close to the ocean, Trimark recommended material upgrades to support long term durability. “We specified stainless steel cabinets to mitigate the corrosive effects of sea air,” said Rudy Troha, Trimark’s Senior Project Manager. “This design is intended to enhance reliability and reduce maintenance costs.”
The power plant control/SCADA system is designed to accommodate both local and remote operations and control. Key site values, alerts, alarms and production reports can all be viewed by the CUC, maintenance staff, and site operators through a secure, browser interface.
Because electric power is an intermittent resource, power generation is directly affected by passing clouds and the position of the sun. As a result, power output from PV sites can vary widely in a matter of minutes. These variations can be problematic for small electric grids.
Ensuring that electricity from PV is stable requires two essential features. First, using advanced logic, the system must stabilize power at the point of interconnection with CUC’s electric grid. Trimark’s T1-S SCADA includes functions that automatically regulate voltage and frequency. Second, the system must communicate securely with CUC’s operations center – sharing real time generation information and accepting authorized commands to adjust power. For example, if weather conditions cause site output to peak and dip with every passing cloud, CUC can request that the site curtail and hold generation at a steady level until weather conditions stabilize. T1-S will not only accept and hold the site at the requested level, it will ensure that all inverters are coordinated to produce the maximum power allowable during the curtailment period, precisely as requested.
News item from Trimark