Saudi Arabia is blessed with some of the world’s largest oil and gas reserves, and is consistently one of the world’s largest oil and gas producers.

The Kingdom has benefitted hugely from the wealth exporting these resources has earned, and is experiencing rapid industrialization and urbanization.

These trends, coupled with an expanding population and the increasing personal wealth of Saudi citizens, are giving rise to significant growth in the Kingdom’s demand for energy. Per capita energy consumption in the Kingdom is twice the world average, and growing at more than 5 percent annually, according to Abdulrahman Ba-Ashin, head of the Middle East Center for Economic Studies.

In many countries industry is the greatest energy consumer.

In Saudi Arabia, however, the building sector places the highest demand on power producers. Central Department of Statistics data shows the sector uses more than 80 percent of the Kingdom’s electricity; predominantly for air conditioning.

Saudi Electricity Company (SEC) predicts a 37 percent increase in demand by 2019. To meet future needs the utility plans to add 47,711 MW between 2014 and 2024.

Oil accounts for 90 percent of the Kingdom’s exports and nearly 75 percent of government revenues.

It is estimated, however, that the Kingdom now consumes about one quarter of the oil it produces.

As a result one of Saudi Arabia’s biggest challenges is meeting businesses and peoples’ need for power in a manner that will not impede the generation of revenues through oil and gas exports.

SEC’s strategy to reduce its oil and gas consumption is multi-faceted.

The number of renewable energy projects has increased significantly.

The utility is investing in more efficient distribution network equipment. Energy efficient technology is being used on an increasing number of new power plants and the efficiency of existing power plants is being increased.

This strategy is bearing fruit. As SEC’s 2014 annual report notes, improving the efficiency of power plants and the distribution network has cut fuel consumption by 12 million barrels.

The utility envisages that, when complete, the program to enhance the efficiency of its older generation assets will save approximately 200 million barrels of fuel annually.

A program to convert simple cycle power stations to combined cycle has made a significant contribution to the improvement of generation efficiency. In a combined-cycle configuration, exhaust gas from a gas turbine-generator is converted to steam, which is used to drive a steam turbine-generator, enabling the plant to produce additional power without an increase in fuel consumption.

It is estimated that conversion from simple to combined cycle can increase the efficiency of a power plant by circa 20 percent.

For SEC, which has a significant number of simple cycle plants, the benefits of conversion are attractive.

As Saleh Al-Awaji, deputy minister for water and electricity, stated in 2012, “Our average thermal efficiency in generation is around 30 to 35 percent. Converting our single-cycle plants to combined-cycle would tremendously increase thermal efficiency to 40 to 45 percent.”

The majority of SEC’s older power stations — which burn gas, diesel or crude oil — are suitable for conversion. Although most of the assets in the conversion program are between ten and 20 years old, some have been in service for up to 40 years. Adjunct to the conversion program, SEC is ensuring that new simple cycle plants are engineered with future conversion to combined cycle in mind.

Currently, SEC plans six more combined cycle conversion projects between 2014 and 2024 which, when complete, will generate 2,411 MW. This equates to circa 5 percent of the 47,711 MW SEC is seeking to add during that period.

The process of converting simple cycle to combined cycle has been in existence for several years, and is becoming increasingly common.

Although the principle for each conversion project is the same the design for each project is bespoke.

Combined cycle systems require considerably more equipment than simple cycle facilities.

As a result, laying out the steam cycle equipment and its auxiliaries in a plant originally designed exclusively for simple cycle can be the most significant challenge.

Typical problems are lack of space to accommodate the new equipment and carrying out construction work at a live power station.

Where the fuel has high sulphur content, as in Saudi Arabia, the design also has to take into account potential corrosion in some of the steam cycle equipment.

The interdependency, or nexus, of energy and water means that SEC’s combined cycle conversion program has benefits other than saving fuel. Although it is a desert kingdom Saudi Arabia consumes 91 percent more water, per captia, than the global average. Water is scarce — it is estimated the Kingdom requires almost a billion gallons a day of additional desalination capacity to meet demand and reserve margin needs by 2020.

With water, as with fuel, the Kingdom is seeking ways to reduce demand. Although power generation is water intensive, combined cycle plants generate nearly 66 percent more energy per unit of water used compared to traditional gas fired plants. So, with more efficient generation SEC is also achieving a reduction in demand for water — which is vital for such an arid country.

— Mazen A. Alami is managing director, Black & Veatch Middle East