Oil has begun to flow from the biggest development project in the North Sea in a decade.
More than 300 million barrels of oil are expected to be produced over the next 30 years from the Mariner field which lies 95 miles east of Shetland.
It is expected to produce annual average plateau rates of around 55,000 barrels of oil per day and up to 70,000 barrels at peak production.
The development will support more than 700 jobs and generate significant revenue in the supply chain for many years to come.
Two months ago Treasury figures showed that oil and gas drove the value of Scotland's exports to the EU up by 18.6% over the last year.
Anders Opedal, Executive Vice President for Technology, Projects and Drilling at Equinor, said:
"By gathering and interpreting new seismic data we have improved our understanding of the oil reservoirs.
"This has resulted in fewer and better placed wells and increased resources since the project was sanctioned in 2012.
"With the significant volumes in place, we see clear potential to further increase oil recovery from the Mariner field and will proactively seek opportunities to do so through the application of new technology, additional drilling and future tie back opportunities.
"With the start-up of Mariner, we have delivered one of the most complex developments in the North Sea.
"We will continue to apply digital solutions and new technology to deliver safe and efficient operations and optimize production."
Kenneth Gibson MSP commented:
“With climate change it is important that Scotland priorities the development of renewable energy, so that a complete switch from fossil fuels can eventually be made. However, with that reality potentially still decades away, it is important that we continue to utilise our own oil and gas, rather than import from the Middle East or other unstable areas of the globe.
“UK Government has long sold Scotland short and downplayed the oil and gas sector, while continuing to syphon off revenues for the Treasury.
“As many of our industries like our food and tourism sectors continue to thrive, Scotland is clearly a wealthy country even without oil and gas. Nevertheless, these resources should benefit everyone in Scotland.
“The only way to ensure our valuable natural resources are protected, rather than exploited by Westminster, is through independence.”