Gigha is an island of the Inner Hebrides, it lies to the west of the Kintyre and is a part of the Argyll and Bute council area. It is 6 miles long from north to south and 1.5 miles wide, with a total area of 5.5 square miles and maximum height 100 metres. Historically Gigha was owned by private landlords until 2002 then Derek Holt, the last private owner, sold the island to the residents of the island for £4.15 million. This was the biggest community buy-out in the UK, heavily funded by the Scottish Land Fund/Lottery (£3.5m), Highland and Islands Enterprise (£0.5m) and the islanders. Now, Gigha Heritage Trust owns the island. When the island was bought, there were major dwelling issues. The community owned 42 properties where 95% of them were rated under the UK standard. A great effort begun for the sustainable development of the land, the improvement of the households and the construction of the first community-owned wind farm connected to the Scottish National grid.
In 2003, the community installed three Vestas wind turbines (WT) with a rating of 225kWh, followed by one Enercon WT rated 330kWh. This gave a total maximum output of 1,005 kWh. In the beginning, the generation was limited to 1MWh due to the low voltage subsea connection, but later on it was proven that the wind farm does not reach the maximum output and the cap was removed. The island covers roughly 70% of its electricity demand from the WTs and any surplus is exported and sold to the grid. The rest of the energy is imported from the grid or from a 1MW back-up Diesel generator. The wind farm generates income from the Enercon WT through the 'Feed in Tariff' and from the three Vestas WTs through the Renewable Obligation Certificate (ROC). The ROC is a green certificate obtained from the government, that rises the price of the electricity sold to the grid as a reward for assisting with the sustainable development of the UK. Today, all the community owned dwellings have been upgraded to UK standards by using the income from the wind farm.
Since 2002 the population has increased from 110 to 163 people and the total number of dwellings is 76. The ROC is expiring in 2027 and the island has already started to plan for their next step. In 2014, Gigha considered installing a Vanadium REDT flow battery but after investigation, the investment was concluded non-profitable and unnecessary since there is not enough surplus coming from the wind farm. There were plans to replace the grid connection with a high voltage subsea cable, but because the cable connection to the Isle of Tiree broke down, Gigha’s replacement was postponed. This project aims to assist Gigha's community with future decisions for sustainable economic development and carbon dioxide reduction [1].