Enhanced efficiency: Considering new technology for cogeneration facilities

Utility plants that produce power alongside desalinated water or steam allow Saudi Arabia to optimise the use of its hydrocarbons resources to support communities living in the country’s hot, arid conditions. Cogeneration facilities have been operating for many years, but the country is trying to press home the advantage by making use of new technologies.

Cogeneration Efficiency

Saudi Arabian Oil Company (Saudi Aramco) is aiming to lead by example with the construction of three new cogeneration facilities as part of a wider energy-efficiency drive across the company. In the firm’s 2013 annual report, which was published in 2014, Khalid Al Falih, the company’s chairman, said, “Saudi Aramco, as a major contributor to the economy and a major energy user in its own right, is a leader in efforts to improve energy efficiency.”

The new cogeneration facilities are being delivered by a Saudi-Japanese consortium, which will build, own and operate the plants for 20 years. Saudi Aramco has a 50% stake in the project, with Marubeni Corporation and JGC Corp of Japan owning 25% and 15%, respectively, and Saudi Aljomaih Energy and Water Company holding the remaining 10%. The three plants are designed to provide 900 MW of power and 1500 tonnes of steam per hour that will be utilised by three Saudi Aramco industrial facilities – Abqaiq oil-processing plant, Hawiyah gas complex and Saudi Aramco’s refinery at Ras Tanura. Marubeni Corporation reported the total cost of the project at $650m and said the facilities should be operating by 2016.

Savings

Saudi Aramco has used cogeneration as an energy-saving tactic for some years and has reduced its annual energy intensity by 2% on average since 2000. This has resulted in savings of 150,000 barrels of oil equivalent per day. Recent examples of the installation or improvement of cogeneration facilities in the company include the generation of more than 1 GW using four cogeneration units at its Shaybah oil field, and a 750-MW power plant at its Wasit gas processing facility that produces 4200 tonnes of molten sulphur a day.

In its 2013 annual report, the Electricity and Cogeneration Regulatory Authority (ECRA) showed that Saudi Aramco, as a licensed electricity supplier, generated 1.7% of the country’s electricity output, or 1189 MW. The hydrocarbons player also has a 6.9% stake in the Saudi Electricity Company (SEC), which is majority owned by the state with a 74.3% holding, with the remaining equity floated on the stock exchange. Strengthening its ties with the utility, Saudi Aramco’s former executive director for power systems, Ziad bin Mohammed Al Shiha, the driving force behind many of its cogeneration initiatives, left the energy company in 2014 to become the new CEO of SEC.

Cogeneration has also enabled the Saline Water Conversion Corporation (SWCC) to become the country’s second-biggest producer of electricity. With facilities configured to optimise the use of energy in power generation and the production of water, it generated 5 GW of electricity in 2013, or 7.2% of the total installed capacity in the Kingdom. According to ECRA, SWCC generated 24.8 GWh of electricity in 2013. Coupling the two processes also reduces the energy requirement for desalination by half.

New Permits

In 2013 ECRA issued three new cogeneration permits. Itlalat Alghad Group was granted a permit for a facility at Rabigh that will produce 1200 MW of electricity along with 480,600 cu metres per day of desalinated water. Mansour Almalik Holding was given permission for a Jubail plant producing 2600 MW of electricity and 300,000 cu metres per day of water. Saudi Aramco was awarded a permit for Safaniya and Khurais Electricity Production, which will create 1510 MW of electricity and 1268 tonnes per hour of steam.

Licensees

Saudi Aramco is also licensed to produce 1189 MW of power and 2859 tonnes of steam per hour at facilities in Riyadh, Abqaiq, Kharsaniya and Yanbu. There are a number of other licensed cogeneration companies in the Kingdom, which first allowed private operators to play a role in power generation and desalination projects in 2004. The Jubail Power Company has 250 MW of capacity for electricity and 510 tonnes per hour of steam; Tihama Power Generation Company’s electricity capacity is 1643 MW combined with 6775 tonnes per hour of steam; Shuqaiq Water and Electricity Company has 1020-MW electricity capacity and 212,000 cu metres per day of water; Rabigh Arab Water and Electricity company has capacities of 600 MW, 192,000 cu metres per day and 4230 tonnes per hour of electricity, water and steam, respectively; and Marafiq in Yanbu produces 1589 MW of electricity and 150,960 cu metres per day of water.

At The Top

The two biggest cogeneration plants are in Jubail and Shuaibah. Jubail Water and Power Company (JWAP) is the world’s largest integrated power and desalination plant, with 2745 MW of electricity capacity and 805,464 cu metres per day of water production capacity. The $3.5bn complex uses multi-effect distillation technology for desalination and combined-cycle power production. Its primary feedstock is natural gas, with diesel used as a backup fuel. The complex was completed in 2010 on a build-own-operate-transfer basis. A consortium led by General Electric and including Hyundai Heavy Industries and Société Internationale de Dessalement d’Eau de Mer acted as the engineering, procurement and construction contractor. Tractebel Engineering acted as the owner’s engineer, while the operations and maintenance contractor, JOML, is a venture of GDF Suez and Nomac (Sogex and ACWA Power). The plant supplies Jubail and the Eastern Province.

Shuaibah Water and Electricity Company (SWEC) is an independent water and power producer. Together with the Shuaibah Expansion Project Company ( SEPCO) the complex is one of the world’s biggest desalination plants. SWEC produces 888,000 cu metres per day of desalinated water while SEPCO has the capacity to produce 150,000 cu metres per day. SWEC also has installed electricity capacity of 1191 MW.

Water and Electricity Company (WEC), a 50:50 joint venture between SWCC and SEC, sources the light crude oil used to power the plant from Saudi Aramco and then supplies it to the project company under a tolling agreement on an energy conversion basis. The project company then sells the entire output of water and power back to WEC. SEPCO was a SR875m ($233.2m) addition to the site, built under a 20-year build-own-operate contract and based on a water purchase agreement.

The project company’s shareholders are made up of corporate and quasi-governmental backers from both Saudi Arabia and Malaysia who share equity in the Saudi Malaysia Water and Electricity Company (SAMAWEC). SAMAWEC in turn owns 60% of the company responsible for SEPCO, with the remaining equity in the hands of the Saudi Arabian Public Investment Fund, which owns 32%, and SEC (8%). The Saudi company involved in SWEC and SEPCO is ACWA power, which was owned by eight local firms until 2013 when two government entities, the Public Investment Fund and the Public Pension Agency, acquired a combined stake of 17.2%.