Submerged Platforms to Revolutionize Offshore Oil and Gas
Efficiency is the new buzzword for the oil and gas industry in case someone’s missed it. But it is more than just a buzzword, at least for some industry players as well as tech giants like German Siemens and Swiss ABB. These two have partnered with E&Ps to bring the concept of automation a step further – a huge step.
Siemens and ABB are competing in the development of automated, unmanned, entirely submerged offshore oil and gas platforms. The advantages of such structures are many, and there are a couple of major challenges to match these. Yet Statoil, which has a reputation for innovative solutions, plans to deploy the first such platform at one of its fields in 2020.
Siemens calls these platforms self-sufficient oil and gas extraction factories, which explains the nature of these structures better. They would remove the risk to human life caused by accidents on traditional platforms. They will, in fact, remove most of the safety risks associated with offshore oil and gas extraction because operators will control them from land.
The seafloor factories would also come with lower maintenance costs due to the lack of workforce needed on them, and the fact that they will be deep below the surface and far from storms. They will be easier to install and dismantle after the productive life of the well ends, which is another huge advantage over traditional platforms.
From a pragmatic perspective, which is the dominant perspective of E&Ps, of course, subsea platforms will be much more productive—they will extract oil and gas directly from the well drilled into the seabed, without the need for miles-long structures that bring the hydrocarbons to the surface. The only thing such a platform would need is a power cable to the surface and a pipeline to move the oil from the well to either land or a floating vessel.
It sounds almost too good to be true, and in a sense, it is. Depths of more than 3,000-4,000 meters, which is where deepwater offshore oil and gas projects are located, present engineers with a unique challenge. The challenge comes in the form of finding materials and components strong enough to withstand the water pressure.
Siemens engineer Jan Erik Lystad puts it succinctly: “We have a kind of torture chamber for technical components,” he says. “We put parts under enormous pressure. The technology has to withstand up to 460 bar — that’s how high the pressure is at a depth of 4,600 meters.” This amount of pressure equals a weight of 469 kilos per square centimeter – a scary weight, especially considering all the different components and structures that have to be able to withstand it, and for a very long time.
Power supply in these circumstances has also been challenging, ABB admits. Power needs to be brought to the submerged structure and distributed among its different parts, the Swiss company says. This means underwater transformers, which are already in operation at traditional platforms, but at minimum load, which will not be the case with an entirely submerged structure with a lot of systems relying on substantial amounts of electricity.
The good news is that there are already cables capable of transmitting electricity at distances of up to 600 km, with multiple loads, which has sort of solved this part of the power supply problem—few, if any, deepwater deposits are more than 600 km from the coast. Solving the puzzle of making this supply safe and reliable is next.
So, engineers are getting there—slowly but surely. Future oil and gas production will come increasingly from offshore deposits, most of them in the deep waters of the world’s oceans, as those on land and in the shallow waters get depleted. Siemens and ABB have a pretty good timing on their projects.