Union Island powered solely by solar for 6 hours

Tuesday, April 16, 2019 was an historic day on Union Island and for the St Vincent Electricity Services Limited (VINLEC).

On that day, the island was powered for approximately six hours solely by solar photovoltaic (PV) and batteries despite less than ideal solar conditions.

The historic event was possible after “the successful completion of the Union Island Solar PV and Battery Energy Storage project last month. Over the past weeks, we have been testing the system to ensure the process runs smoothly. The Company is pleased with the outcome in this noteworthy project,” a post on VINLEC’s Facebook page said on Tuesday.

“In the near future, the solar PV farm will generate electricity on the island during the day to supply to the grid. We anticipate that on sunny days, the solar plant will generate excess electricity than is required to supply the average daytime load on the island. The excess electricity will be stored in batteries. The expected annual energy output is approximately 32 per cent of the electricity generated in Union Island in 2018.

“VINLEC wishes to express sincerest thanks to the residents of Union Island for their support and understanding during this process,” the post said.

Dr Vaughn Lewis, VINLEC’s manager, engineering told SEARCHLIGHT that Tuesday was the first full day of performance testing of the project. He said that at about 8:30 am on Tuesday, solar generation was high enough for the automated system to turn off one of two running generators.

“The system then automatically turned off the second generator just after 10 am when solar was strong enough and the battery sufficiently charged to deal with fluctuations of solar output. The island was powered for approximately six hours from solar and batteries only, despite less than ideal solar conditions,” Lewis said The system switched the first generator back on just before 4 pm and the second around half an hour later.

Lewis said VINLEC plans to suspend performance testing of the system until next week after the long and very busy weekend for the island. He however said on completion of performance testing, the mode in which the Union Island power plant operated last Tuesday, will become the normal mode of operation.

Lewis said VINLEC is on the leading edge in relation to its ability to supply its customers solely from solar and batteries for a period during the day.

This, he said, is a first for a utility company in the English speaking Caribbean.

And if all goes according to plan, a similar solar PV and battery energy storage system on Mayreau should become operational by August.

“We also plan to bring battery storage technology to the mainland in 2020 to improve efficiency and reliability,” Lewis said.

The UAE-CREF Union Island 600KW Solar PV Battery Hybrid Power Plant was officially opened on March 25, 2019. The project was funded under the UAE Caribbean Renewable Energy Fund at a cost of US$3 million and developed in collaboration with VINLEC on behalf of the Government of SVG.

The Solar Panel Plant displaces 320,000 litres of diesel fuel per year at savings of EC$500,000.