GE-Led Study Reaffirms Barbados Light & Power’s Renewable Power Integration Capabilities

In order to develop a comprehensive assessment on the impact of increased penetrations of wind and solar generation resources on the operation of its island grid, Barbados Light & Power Corporation (BLPC) enlisted GE’s Energy Consulting business to lead its Barbados Renewable Integration Study (BRIS).

The goal of the BRIS was to assess the technical and economic impact of intermittent renewable energy resources on the generation, transmission and distribution system of the BLPC. The study addressed the potential challenges of operating BLPC’s power system with increasing levels of wind and solar power generation and provided recommendations on:

• Any necessary changes to the requirements and standards for interconnecting intermittent renewable energy resources to the Barbados grid system.
• The maximum allowable intermittent renewable energy limit that can be accommodated on the existing system without mitigation measures.
• Mitigation measures, including energy storage technologies, and associated costs to accommodate renewable energy for the scenarios presented.

The study was conducted to determine the long-term impact of renewables. Overall, four scenarios were chosen to be analyzed, ranging from a business-as-usual reference case with wind and solar resources at current levels to a scenario with 16 percent of annual energy provided by wind and solar resources.

GE’s Energy Consulting business led the overall project, modeling the production cost and analyzing the capacity value, dynamic stability and distribution system of the Barbados power grid. To execute the broad range of technical analysis required for this study, GE worked closely with the BLPC to understand its system and operations. AWS Truepower provided the chronological two-second wind and solar data used for the study.

“The integrated planning study was the first of its kind done by the utility; it included specialized and complex wind and solar models to help determine the results. The local regulators, The Fair Trading Commission, are ultimately responsible for the decision to increase the allowable amount of intermittent energy, but this study provides key information to help them in making their determination,” said Johann Greaves, BLPC systems planning and performance manager.

The GE-led study found that no insurmountable operating challenges were uncovered when connecting up to 20 megawatts (MW) of distributed photovoltaic (PV), 15 MW of wind and 20 MW of centralized PV generation to the Barbados power grid. This was primarily enabled by carrying additional regulating reserves and did not require extensive mitigations to the system or operations. The study noted that minimal curtailment of the renewable generation would be needed.

The following mitigation measures are required to improve the reliability and security of BLPC’s grid under the examined renewable energy penetration limits:

• Spinning reserves to counteract variability of wind and solar.
• Automatic generation control for improved frequency regulation.
• Frequency and voltage ride-through capability on all renewable energy plants.
• Governor droop response from thermal and renewable plants.
• Improved voltage control on distribution feeders.

Voltage and frequency ride-through capability on all new distributed PV systems is especially critical for Barbados since distributed PV is likely to be the dominant type of renewable energy resource on the island. Based on the results of this study, Barbados Light & Power was able to increase the permissible limits on the country’s renewable energy rider from 9 MW to 20 MW, allowing continued growth for the Barbados solar industry.

“The integration of renewable power generation resources such as solar and wind onto the grid is integral to the sustainability of today’s power grids,” said Gene Hinkle, managing director, power economics, GE’s Energy Consulting business. “There has been a considerable shift toward cleaner and more sustainable energy production around the world, increasing the need for utilities to be able to accommodate the power produced by renewable sources and turn it into useable power on their networks. The complete analysis of BLPC’s power grid equips the company with valuable insight into the future of its renewable integration capabilities.”

The study also showed that renewable generation reduced the operating cost by $19-62.5 million per year. These savings could be used to offset capital costs and modifications in operating practices.