Offshore fields use power sent from land

Offshore oil and gas fields supply much of the world's energy, but it is not always appreciated that the very platforms extracting and delivering supplies to shore are themselves considerable consumers of fuel.

Larger platforms deployed in the North Sea can typically consume power at a rate of 50 to 100 megawatts across a large range of processes - including oil separation, gas compression, wastewater treatment, gas lifting, and the ultimate export of oil and gas to shore.

One study suggests that more than a quarter of Norway's total carbon dioxide emissions could be attributed to North Sea oil and gas platforms operating in its waters at the beginning of the decade.

However, a combination of environmental lobbying, engineering problem-solving and economic calculations have prompted the oil-rich nation to raise its game.

Statoil, Norway's oil industry champion, announced last month the award of a $155m contract to engineering company ABB for initial work on the first stages of a land-based power supply for the development of the Johan Sverdrup field - the biggest North Sea oil discovery of recent years.

In total, partners backing the scheme are budgeting more than five times that amount to send power from Norway's grid system, which is normally fully supplied by the country's abundant hydro­electricity, via a high-voltage, direct current cable to help fuel oil and gas extraction from 2019 onwards.

A 200km long submarine cable should have the capacity also to power adjacent fields scheduled for development from 2022, in line with commitments demanded by a coalition of Norwegian political parties last year to secure public backing for the launch of production from Johan Sverdrup.

<

The tabular content relating to this article is not available to view. Apologies in advance for the inconvenience caused.

Other hydrocarbon operators appear to be learning that tapping grid supplies can make reputational as well as economic sense - particularly when these supplies are derived in part from renewable or low-carbon sources not always fully exploited by other industries.

The first power-from-shore oilfield cable was installed in Saudi Arabia's Abu Safah development 50km into the Persian Gulf in 2003. Since then, two Norwegian platforms - Statoil's Troll and BP's Valhall facilities - have also tapped electricity from land rather than rely solely on gas turbines on board.

But in spite of growing pressure from environmental lobbies and economic self-interest, such energy-saving measures remain the exception rather than the rule.

© The Financial Times Limited 2015. All rights reserved.
FT and Financial Times are trademarks of the Financial Times Ltd.
Not to be redistributed, copied or modified in any way.
Euro2day.gr is solely responsible for providing this translation and the Financial Times Limited does not accept any liability for the accuracy or quality of the translation