FEATURE: Piecing together the evidence on Turkey's Sakarya gas field plans

Ankara — Turkish officials have begun to give more information on plans to develop the 405 Bcm Sakarya gas field, discovered in the Black Sea last year by state upstream operator TPAO.

Rather than present a comprehensive plan, however, details have emerged in bits and pieces, both directly from official briefings and official documents, and from un-sourced reports in state-run media, some of which has subsequently being denied by officials.

In short, important questions remain, such as: what will field development cost? Will TPAO indeed require partners with deep water gas production experience? How much recoverable gas does the field hold? And can a 2023 deadline for first gas possible be met?

In August last year Ankara announced TPAO's drill ship Fatih had discovered a 250 square kilometer gas field, 150 km offshore Turkey's west Black Sea coast.

Reserves were initially announced as 320 Bcm, later increased to 405 Bcm as the Tuna-1 well located a second deeper reservoir, with Ankara targeting delivering first gas to customers by 2023.

Initial annual production could start at around 3-4 Bcm/yr, rising to a plateau of around 10 Bcm/yr. Further drilling, it was suggested, would confirm the size of the field.

As yet no results have been announced for Turkali 1 well, which the Fatih began drilling in November, or the Turkali 2 which it began drilling in January.

International involvement

Official statements initially insisted the field would be developed by TPAO alone using "domestic resources", a mantra that played into the emerging narrative that the discovery would (at least in part) free Turkey from dependence on expensive imported gas imports and would be celebrated as part of the republic's centenary in 2023.

As TPAO has experience of deepwater field development and production, and its deepwater drill ships are crewed by experienced foreign personnel, this was later modified to TPAO not taking on "international partners" and instead buying in necessary expertise.

This may still be the plan, but recent news reports have claimed that Ankara is in talks with unnamed international companies, while energy minister Fatih Donmez on March 3 told Turkish reporters that TPAO was working with "both domestic and international companies".

Donmez confirmed drilling in the field would continue with the Fatih and another vessel, the Kanuni, which is expected to commence drilling its first well in April.

He has not commented on recent media reports claiming TPAO was in talks with a Norwegian company to buy another drill ship to be used in the Black Sea.

EIA detail

Some further insight was given in TPAO's Environmental Impact Assessment (EIA) for the project published in February.

This states phase one production would involve 6-10 wells producing up 10 million cu m/d "by 2023", with Phase two, described only as happening "after 2023", seeing 30-40 production wells, producing 40 million cu m/d, requiring construction of a second pipeline of 24 inch diameter.

The report confirmed production would use unmanned subsea facilities, feeding gas to a subsea manifold then to be transited onshore via a 155-km, 16 inch diameter pipeline.

Gas would then be cleaned at a processing plant to be constructed on a site at Filyos - for which Donmez has separately confirmed a site has been acquired.

Tight deadline

Much remains to be done if first gas is to be delivered to customers by the republic's centenary in 2023, with the political goal looking increasingly out of kilter with the geological, technical and environmental challenges, or indeed the commercial viability, of bringing the Sakarya field to completion.

To date no official details have been released on costing or of how and when the various parts of the project will be tendered, with Donmez saying only that the project involves "20-30 investment items."

State news agency Anatolia reported in February that TPAO is to spend around $111 million on subsea facilities, but without clarifying if this was for the initial six to 10 wells and one pipeline planned or for all 30-40 wells and both pipelines, while a subsequent report by Bloomberg quoting unnamed "official" sources suggested the whole project would cost in the region of $3.2 billion, seen as a more realistic assessment by analysts.

Further drilling ahead

Meanwhile early reports suggesting plateau production of around 10 Bcm/yr appear to have been contradicted by TPAO's EIA report which suggests a plateau of around 14.6 Bcm/yr.

While the 48-inch pipeline Botas' plans to construct to transit the Sakarya gas into its grid, would have a capacity of up to 25 Bcm/yr.

Does this indicate an official belief that more gas may be found? Donmez suggested as much on March 3, confirming TPAO would scan a further 10,000 km in the Black Sea and will drill if results suggest possible reserves.

Whether this additional exploration work comes to anything remains to be seen. Previous scans have been conducted and over the past two decades ExxonMobil, Chevron, Petrobras, BP and Shell have all drilled promising blocks in the Turkish Black Sea and departed without declaring any discoveries.