Policy & Legislation
Monday, 15 October 2012 15:20

A salient future: South Africa set to tap into desalination

Could desalination mitigate South Africa’s growing demand for fresh water? According to the South Africa Desalination Market Forecast and Opportunities, 2017, conducted by TechSci Research, the answer is a clear yes.

Karien Slabbert

Recent market research states that desalination will in future become an integral part of South Africa’s water resources. Water 360 highlights the key drivers of the local and international desalination industry.

Mitigating a dry spell

South Africa is characterised by water shortages and periodical droughts, which makes it one of the most water-scarce countries in the world. According to the United Nations World Water Development Report 2012, it ranks 148 out of 180 countries for water availability per capita. Growing fresh-water demands due to rising living standards, a growing population with growing water needs, industrial and agricultural developments have all placed tremendous pressure on the country’s finite water resources.

These recurring stock phrases necessitate innovative thinking and a paradigm shift. Within this water scarcity and quality conundrum, South Africa has been required to look at alternative water resources and recycling options. It seems that the tides are turning towards desalination as a viable fresh-water solution.

Desalination is the process where salt and other minerals are removed from saltwater and brackish water in order to produce fresh water suitable for human consumption, as well as water for irrigation and industrial purposes.

Due to the earth’s extensive ocean surface, 97,5% of water is considered saline and the remaining 2,5% is fresh water. With the right technology and implementation, this presents infinite possibilities for desalination. Unsurprisingly, in 2011 the global water desalination market reached US$ 14,31-billion. Recently an increased demand for desalinated water in emerging economies and desert countries such as the United Arab Emirates has driven this growth.

A salient future

According to a recently published report by the global research-based management consulting firm TechSci Research, South Africa Desalination Market Forecast & Opportunities, 2017, the country’s desalination market has huge growth potential. The report states that the desalination market is set to grow at a compound annual growth rate (CAGR) of 28% within the next five years. “The future of the desalination market in South Africa seems very promising, as there is a persistent water shortage problem and the available sources of pure water are being increasingly stretched. The availability of seawater across South Africa’s coastal regions and the introduction of less energy-consuming technologies are set to be key drivers,” states the report.

“South Africa’s desalination market is at its nascent stage where the government has recently started encouraging it for meeting fresh-water demand in the country. It is forecasted that the number of plants in South Africa will triple by 2017,” notes Karan Chechi, research director at TechSci Research. Chechi says the growing water demand and the depleting water resources have made it imperative for the South African administration to look at desalination for their growing water requirements. “Recent developments in the market are taking place in the form of new plants being set up by the municipalities and this trend will follow for a long time as the desalination market in South Africa is still a niche market.” Moreover, the technological advances in the desalination industry are forecasted to give a much-awaited thrust to this market in South Africa.

SA water resource strategy

An important aspect one should bear in mind is whether the South African government is considering the desalination of seawater as a potential water resource. More importantly, will it be viewed as a long-term strategy or merely as an emergency measure?

South Africa’s Department of Water Affairs (DWA) foresees that by 2030 up to 10% of the country’s urban water supply could come from water desalination plants. The Draft National Water Resource Strategy 2 (NWRS2): Managing Water for Managing Water for an Equitable Resource Strategy, which was recently approved by the cabinet for comment, states that the national government recognises that desalination will play an important role in South Africa’s future water security.

The strategy states: “The DWA will ensure that desalination is properly considered as an option for meeting future water requirements in its integrated water resource planning processes, and will actively promote and support the development and implementation of desalination projects where these projects compare favourably to other alternative options, taking into account the benefits of the diversity of water supply in the context of increased climate change risk.”

Key desalination-related objectives and actions of The Draft National Water Resource Strategy 2 (NWRS2) strategy are:
•    Integrating energy and water planning.
•    Improved water-quality regulations.
•    Streamlining regulatory approval processes.
•    Research and development.
•    Financing desalination projects.
•    Implementing large-scale seawater desalination projects.
•    Desalinating and treating acid mine water.
•    Development of skills and local capacity.
•    Increasing public awareness and acceptance.
•    Developing guidelines.

A future-focused perspective

Desalination technology is widely used across the world and it makes good common sense for a water-scarce country like South Africa to follow the same strategy. If the draft water strategy is ratified, desalination in South Africa will be backed by the government and will therefore have a greater chance of becoming a viable alternative to freshwater resources, as seen in both developing and developed countries.

The downside

However, no solution could be considered truly viable without considering the environmental impact and electricity safety of the technology. Despite all its benefits, desalination does not offer a “silver bullet” solution to the world´s growing water problems, according to www.mediaclubsouthafrica.co.za. “Besides using very expensive equipment, the process also uses a considerable amount of electricity and is not without environmental consequences,” states the website.

The ocean consists of highly sensitive, complex ecosystems. “Both the intake and discharge processes of the water may affect water quality and marine life. Aquatic species have a tolerance for natural salinity, an aspect which may be affected by the highly concentrated seawater which is pumped back into the ocean,” states www.mediaclubsouthafrica.co.za.

And while the intake structure is designed to maintain a flow of less than 0,15 metres per second – the minimum escape velocity for aquatic species – there is still a risk that plants, fish eggs and fish larvae around the intake areas may die. The process also uses chemicals which, if left untreated, can be harmful to the environment.

An international perspective

Developed country

Germany: Development and urbanisation has led to a fresh-water shortfall in Germany, states TechSci Research’s Germany Desalination Market Forecast & Opportunities, 2017. As the second-largest country in the European Union after Russia, Germany still has major water resources available. However, the situation is changing at a rapid rate. Higher population rates, industrialisation and a demand for fresh water has been driving Germany’s desalination market, which is all set to grow further at a CAGR of 11% for the next five years. The German market has a major contribution of reverse osmosis technology, but in coming years multi-effect desalination (MED) is expected to witness faster growth due to an increase in industrial desalination plants.

Developing countries

China: A population boom, industrialisation, urbanisation, low rainfall and a never-ending demand for fresh water has been driving China’s desalination market, which is all set to grow further at a CAGR of about 18% for the next the five years. According to TechSci Research’s China Desalination Market Forecast & Opportunities, 2017, the country’s desalination market will witness phenomenal growth in the next five years, as market size has doubled in the last three years. Key drivers in the growing desalination market are enormous industrial and economic growth. Industrial demand of desalinated water has contributed the most and the same trend is anticipated in the future.

India: India’s water desalination market will witness phenomenal growth in the next five years as the market size has doubled in the last three years, according to TechSci Research’s India Desalination Market Forecast & Opportunities, 2017. The country’s water desalination market is set to grow at a CAGR of 22% for the next five years. Some of the drivers for the growing desalination industry include enormous industrial and economic growth, as well as increasing water scarcity. Government support has driven the industry and is expected to continue as India currently has a 33% scarcity of available fresh water.

Desalination practices

Membrane-based technologies

Membrane-based technologies are considered 23% more cost-effective for generating desalinated water when compared with thermal-based desalination practices.

Multi-effect desalination (MED)

A multi-effect desalination (MED) unit is an evaporator where seawater is evaporated in one or more (up to 14) evaporation stages at a low temperature (< 70°C) in order to produce clean distillate water. The MED process is designed to produce distilled water with steam or waste heat from power production or chemical processes, and/or to produce potable water, according to www.entropie.com.

Reverse osmosis

Reverse osmosis has proved to be the most reliable and cost-effective method of desalinating water, and hence its use has become more widely used. According to the desalination company Aquamarine Water Treatment, energy consumption is usually some 70% less than for comparable evaporation technologies. Advancements have been made in membrane technology, resulting in stable, long-lived membrane elements. Component parts have also been improved, reducing maintenance and downtime. 

Additional advancements in pre-treatment have been made in recent years, further extending membrane life and improving performance. Reverse osmosis delivers product water or permeate having essentially the same temperature as the raw water source (an increase of 1°C), which may occur due to pumping and friction in the piping). This is more desirable than the hot water produced by evaporation technologies.

Full acknowledgement and thanks are given to the TechSci Research South Africa Desalination Market Forecast and Opportunities, 2017, TechSci Research Germany Water Desalination Plants Market Forecast & Opportunities, 2017, TechSci Research India Desalination Market Forecast & Opportunities, 2017, TechSci Research China Desalination Market Forecast & Opportunities, 2017, www.aquamarinewater.co.za, The Proposed National Water Resource Strategy 2 (NWRS2): Managing Water for fan Equitable Resource Strategy, United Nations World Water Development Report 2012, www.entropie.com and www.mediaclubsouthafrica.co.za.

GIL Africa 2017