First oil flowed from the Tweneboa, Enyenra, Ntomme (TEN) fields offshore Ghana, to the FPSO Prof. John Evans Atta Mills in August 2016. This milestone was reached on time and on budget three years after the Plan of Development was approved by the Government of Ghana in May 2013.
In March 2009, the Eirik Raude rig successfully drilled the Tweneboa-1 wildcat well in the Deepwater Tano licence, around 20 km west of Tullow’s Jubilee field and some 45 km offshore from the Ghana mainland. This initial discovery was followed up by a series of further successful appraisal and exploration wells which resulted in the discovery of the Tweneboa-Enyenra-Ntomme (TEN) field.
In May 2013, The Ghana Minister of Energy approved the Plan of Development for the field and Tullow commenced with its second major operated deep water development project in Ghana. Similar to Jubilee, the development includes the use of an FPSO which has a facility production capacity of 80,000 bopd which will be tied in to subsea infrastructure across the field. The vessel was converted in Singapore and in September 2015, the vessel was officially named ‘FPSO Prof. John Evans Atta Mills’, after the late Ghanaian president who oversaw First Oil from Ghana’s Jubilee Field in 2010. The FPSO sailed away from Singapore to Ghana on 23 January 2016.
The FPSO arrived in Ghana in early March 2016 where it was moored to the seabed before being connected to the risers and subsea infrastructure.
First oil was achieved on time and on budget in August 2016, three years after the Plan of Development was approved by the Government of Ghana.
Following first oil, the oil production, gas compression/injection and water injection systems were commissioned and are now operational. In early January 2017, the capacity of the FPSO was successfully tested at an average rate of over 80,000 bopd during a 24 hour flow test.
Gross annualised working interest production in 2016 averaged 14,600 bopd (net: 6,900 bopd).
Production testing and initial results from the 11 wells indicate reserves estimates for both Ntomme and Enyenra to be in line with previously guided expectations. However, due to some issues with managing pressures in the Enyenra reservoir and because no new wells can be drilled until after the ITLOS ruling later this year, Tullow plans to manage the existing wells in a prudent and sustainable manner. As a result, Tullow expects production from TEN to be around 50,000 bopd (net: 23,600bopd) in 2017, although work continues to consider ways to increase production in 2017.
In April 2015, the Special Chamber of the International Tribunal of the Law of the Sea (ITLOS) in Hamburg rejected Côte d’Ivoire’s request that Ghana be ordered to suspend all oil exploration and exploitation in the disputed zone including the TEN Project. ITLOS ordered a number of provisional measures which both Ghana and Côte d’Ivoire are required to comply with; including continued cooperation and ‘no new drilling’ until ITLOS gives its decision on the maritime boundary dispute which is expected in late 2017. It is therefore assumed that development drilling will not recommence until the ITLOS proceedings have completed.