Total's Shetland Gas Plant officially opened

A huge new gas plant that is bringing reserves west of Shetland to the mainland has been officially opened.

The Shetland Gas Plant is said by operator Total to be capable of supplying energy to two million homes.

It began processing gas from the vast Laggan and Tormore fields, north west of Shetland, in February.

The plant is said to have been the biggest construction project in the UK since the London Olympics.

• Will Total make a return at current gas prices?

Almost one fifth of the UK's remaining oil and gas reserves are thought to lie in the area to the west of Shetland.

Total said the Laggan and Tormore fields will produce 90,000 barrels of oil equivalent per day.

It is expected to provide about 8% of the UK's gas needs - the equivalent of about two million homes.

The gas is piped to the plant, which lies just to the east of the existing Sullom Voe Terminal, before a pipeline takes it to the UK mainland and into the national gas grid.

The project is part of a massive £3.5bn investment by French company Total. Challenging weather conditions delayed the project by more than a year and added millions to its cost.

Total chairman Patrick Pouyanne said: "The Laggan-Tormore development demonstrates Total's continued commitment to the United Kingdom.

"By opening up its third production hub in the frontier deep offshore waters of the West of Shetland, Total is also improving the United Kingdom's long-term energy security.

"This subsea-to-shore development is the first of its kind in the country and will provide the domestic market with 8% of its daily gas requirements while enabling the potential for further developments in the West of Shetland area."

The Laggan and Tormore fields are on the edge of the UK continental shelf, where water depths descend rapidly from an average of 120m to 600m and beyond.

Dong Oil and Gas chief executive David Cook added: "We are proud to be a partner in this flagship project which is a great example of Dong Energy playing a key role in the delivery of the UK's long-term energy requirements.

"Together with operator Total and our partner SSE, we have overcome many challenges to deliver the project from exploration through appraisal, development and into operation."

What are the Laggan-Tormore fields?

• The fields lie in a region geographically closer to the North Atlantic than the North Sea, about 77 miles (125km) north west of Shetland

• Water depths there descend rapidly from an average of 120 metres (393ft) to more than 600 metres (1,968ft).

• Until February, only oil was recoverable from the area

• Now, with the pipelines and infrastructure in place, much of the energy which was previously inaccessible can be reached

• The development has four subsea wells which will connect it to the new onshore Shetland Gas Plant

• The plant has the capacity to handle 500 million standard cubic feet of gas each day

• Following treatment at the plant, the gas will then be exported to the mainland

The Shetland Gas Plant construction phase was estimated to have involved up to 800 jobs, with 70 full time posts in plant operation.

As well as the onshore construction, there was a major programme of subsea infrastructure and pipelines.

It has been built on a peat bog next to the Sullom Voe oil terminal.

The gas plant was said to have been the largest construction project in the UK since the London Olympics