When Oman’s national oil company Petroleum Development Oman (PDO) announced in 2010 that it was considering using a solar-powered thermal enhanced oil recovery (EOR) technology to extract crude from the heavy oil formation in its Amal oil field, many eyebrows were raised across the industry. The EOR technique under consideration – injecting steam produced by sunlight-gathering glasshouses into an oil field – had never been used in the region before.

Eyebrows lifted further when it became known that PDO had hired little-known California-based firm GlassPoint to conduct a pilot study to test the viability of the solar-based thermal technique in the southern Omani desert.

Miraah project

GlassPoint began work on a pilot project in 2012, and finished construction the following year – yielding initial results that encouraged PDO enough to award the supplier a contract to build a full-scale development in 2015. Work on the project began in October of that year, and in November 2017 the first block of the Miraah project began delivering steam to the Amal West oil field.

“Solar is clean energy. At the time that we embarked upon this project, we were also looking at the gas shortage in Oman. Several projects were getting delayed because of lack of gas. We needed to produce steam to extract this heavy oil. That’s why this [work on Miraah] started,” says Ali al-Gheithy, petroleum engineering function director at PDO.

“By using solar, you could save a lot of gas that can be used for other purposes and other industries. So that was a motivation from our side,” Al-Gheithy tells MEED.

Reducing emissions

When fully operational, Miraah will be a 1,021MW solar plant generating an average of 6,000 tonnes of solar steam a day for EOR, dwarfing all other solar EOR installations. The project is expected to reduce CO2 emissions by more than 300,000 tonnes a year. Miraah is also expected to save about 5.6 trillion BTUs of natural gas a year, an amount of gas that could be used to provide residential electricity to 209,000 people in Oman.

The Miraah solar plant will generate an average of 6,000 tonnes of solar steam a day for EOR

The $600m Miraah facility, including all the supporting infrastructure, is spread across 3 square kilometres. “The whole project will have 36 greenhouse modules. These will be operating in groups of four, so we will be completing four greenhouse modules at a time. The entire supply chain is working to complete the project,” Al-Gheithy says.

Regional leader

Even before the Miraah project became operational, Oman had established itself as a regional leader in the EOR domain. The project has now cemented PDO’s position in the market.

Heavy oil accounts for 44 per cent of PDO’s total reserves, meaning the Omani major has to resort to EOR to maintain the 600,000 barrels it currently produces each day. “56 per cent of the easy oil has been exploited already, so now it’s just the heavy oil that we have to contend with. There are oil fields similar to Amal, like Thayfut and Habhab, which could see the next phase of solar EOR in Oman. There are fields where the solar EOR technology can be exploited. We are studying the feasibility of producing oil from these fields [using solar EOR methods],” Al-Gheithy says.

Chemical and gas injection

Solar-based thermal EOR may account for most of PDO’s EOR activity, but the exploration and production (E&P) company, which owns about 70 per cent of the sultanate’s oil and gas reserves, is also involved in the two other forms of EOR, chemical and gas injection, in other fields within its 120-strong portfolio.

“We are injecting polymers into the Marmul field through alkaline surfactant polymer flooding, and doing a polymer pilot project for the Nimr field. We are also doing miscible gas-based EOR in the Rabab Harweel project. We are doing another kind of thermal project in a carbonate reservoir called Qarn Alam, and we are also performing thermal-assisted EOR for the Amin and Amal South fields, which are similar to Amal in terms of their carbonate reservoirs,” Al-Gheithy says.

Eyeing partnerships

Most importantly, PDO has identified collaboration as a key strategy in continuing to produce oil through EOR, and is eyeing partnerships with service providers like GlassPoint, as well as joint projects with operators. PDO has devised a business model called Heavy Oil Production Sharing Agreement (HOPSA) for partnering with other players. The impetus for this stems from PDO’s ambition to produce oil from one of its standalone assets, the Habhab field in the south, which is estimated to hold reserves of one billion barrels.

Al-Gheithy explains: “Habhab is a very large oil field containing heavy oil, and is extremely tight. So, in terms of looking at an EOR technology that could unlock this, it is beyond the technologies that are currently available.

“But what we can do is invite partners to come up with effective technologies, to do research and development, pilots and trials for PDO to exploit this huge opportunity.”

The HOPSA model, Al-Gheithy says, presents a strong value proposition for any company with the technology that could not only help PDO unlock the potential of the Hahhab field, but also engage in E&P activities in relation to similar PDO assets in future. “If the model bears results, it will be a win-win [situation] for both PDO and the partner company,” he concludes.

Ali al-Gheithy: biography

2010-present: Petroleum engineering function director, PDO

1993: Joined PDO

1993: Earned a PhD from Imperial College, London

1988: Graduated from the University of Tulsa, US, with a BSc degree in petroleum engineering