Already in January there were signs of stress. Crude oil shipments from Nigeria have, Ecobank says, declined from 75 cargoes in January to a scheduled 59 in March, and there is an unsold overhang of 21 out of 65 February cargoes. This is an unusual situation given that the cargoes contain Nigeria's premium grades of sweet and light crude, which are usually very much in demand.
As Rolake Akinkugbe, head of energy research at Ecobank, explained to beyondbrics, refiners in Asia are increasingly capable of handling larger volumes of sour crude oil grades, while European refiners are facing pressures on their margins and seeking lower-priced inputs. Neither are looking as favourably upon Nigerian oil grades, which are priced at a substantial premium to the sour grades from the Middle East.
"Nigeria and other oil producers in west Africa had a window of opportunity during the Libya crisis when their [Libya's] supply was taken off the market", she said. "There was a great switch to African crude grades, which partly accounts for their pricing premium at the moment."
Libyan oil is now coming back online, but the major problem for Nigerian crude is the soaring volumes of shale oil being produced in the US. The US is still Nigeria's biggest oil export destination, but the relationship can no longer be taken for granted.
"A decade ago" says Akinkugbe, "the industry thought that by 2015 around 25 per cent of America's oil would come from west Africa, but now there's a dramatic change in that picture. African governments need to look for alternatives destinations."
In recent years, she says, producers in west Africa and the Gulf of Guinea have exported around 2mbpd of oil to north America, but this has fallen to around 1mbpd, with the slump in Nigerian exports to the US being particularly severe due to the steeper price of its crude. Having accounted for 12 per cent of US crude imports in 2011, Nigeria's share fell to 6 per cent in 2012.
Nigerian oil exports to the US, Ecobank says, have already slumped to 700,000bpd from the 2012 average of 800,000bpd, and that could fall as far as 580,000bpd in 2013 as US domestic oil producers add an expected 800,000bpd of new capacity.
As if the stiff new competition from Texas and North Dakota were not enough, Nigeria's oil industry also has sizeable domestic problems too. Theft and pipeline vandalism cost it $7bn in 2012 according to the International Energy Agency, and uncertainty surrounding the long-awaited Petroleum Industry Bill is causing nervous oil companies to hold back investment.
Oil and gas make up 94 per cent of Nigerian exports, and so even a small slackening of demand for its hydrocarbons spells big trouble. No wonder senior figures in the Nigerian government seem to have been talking so much about economic diversification recently.
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