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Field of View bringing four drill strings back into use, as well as investing in everything from the cranes through to the export pumps and a new gas and power ring main around the feld – until then each facility was powered locally – with four new gas-powered turbines installed (20 older units could then be removed), and issues that beset the export system were also resolved. All of which has helped increase production effciency and lifting costs.

The year after the feld was scheduled to cease production, Apache installed a new platform, the Forties Alpha Satellite

Platform (FASP), adding 18 new wells slots and increasing compression, power generation and processing capacity.

As a result, in 2012 through 2014,

Forties ranked as the second highest pro- th ducer in the North Sea, compared to 10 in 2003. And the investment continues.

For Towart, the key drivers to the success of the feld has been adding new barrels through the drill bit and ensur- at Laing Offshore, near Hartlepool, and story. Apache has gone on to produce ing they get produced effciently while the Highlands at Highland Fabricators at about 240 MMbo (120 MMbo from replenishing the target inventory and

Nigg Bay on the Cromarty Firth. In 1979, Apache drilled wells) from Forties and continuing steady capital investment. production peaked at 550,000 b/d, higher thinks there’s another 100 MMbo to be

Drilling than initial predictions. In 1986, Forties had, Davenport said, speaking at SPE “Often people characterize the success

Echo was installed, followed by the Annual Technology Conference and at Forties around the aggressive drilling

Unity riser platform in 1993. Exhibition last year. program,” he says. “The drilling program

Forties Alpha, Charlie and Delta are

Investment has averaged about 13 wells per year over self-contained drilling, production and the last 10 years. Last year, we drilled processing units, with Bravo no longer A huge piece around Apache’s success 17 wells. We had fve consecutive drill processing fuids, but directly exporting on Forties has been investment. Since strings running in the feld and that was a them to Charlie for processing. Echo, 2003, Apache has spent some $5 billion new record in Forties history.” Some 75% having no processing facilities, exports on Forties’ infrastructure and drilling, its production fuids for processing via the Alpha platform. Charlie acts as a gathering platform. Processed fuids are exported to Cruden Bay and onwards to

Kinneil via the Forties Pipeline System.

When production started in 1975, it was predicted Forties would stop producing in the early 1990s. By 1990, that was moved forward to 2000. Projects like the Forties

Artifcial Lift Project in the early 1990s, with gas lift and electrical submersible pumps, helped extend the feld’s life, and, as of 2002, Forties had produced about 2.5 billion boe, somewhere a little more than 50% of its reserves.

Then, BP decided to sell the feld, its “crown jewels,” for US$683 million to

Apache. At the time, Forties was pro- ducing 41,000 boe/d and the remaining reserves were estimated to be 144 MMboe, with feld life expected to end in 2012.

A new start

What happened next was a huge success

A BP Archive photo from Forties from the 1970s. Reproduced with permission from BP Archive oedigital.com September 2015 | OE 21 020_OE0915_Field of View.indd 21 8/19/15 8:56 PM