Is Desalination Expensive?

It’s the sustainable solution for water scarcity challenges, but is it financially viable?

With the global population continuing to increase, the demand for fresh water and the pressure on natural resources increases too. If water consumption patterns continue on their current trajectory, it is expected that the demand for water will exceed supply by 40% in 2030.

While water covers most of the Earth’s surface, the amount of fresh water is limited. Only 3% of all the water on our planet is fresh water, and only 0.5% is readily accessible. The remaining 2.5% is locked up in ice sheets, glaciers, soils, and the atmosphere, or it lies deep under the surface or is too polluted to be used. The remaining 97% is salt water, which is extremely abundant, and through desalination can be turned into safe drinking water.

Reverse osmosis is the most widely used desalination method, although it comes with economic and environmental challenges. Let’s explore the factors influencing desalination expenses and find out why it can be a valuable investment amid growing water challenges.

Desalination’s Initial Investment

The upfront costs of establishing a desalination plant can vary significantly based on several factors, including the plant’s capacity, the technology used, where the plant is located, and specific project requirements. Here are some of the key components that contribute to those upfront costs:

• Plant Size: The capacity of the desalination plant, typically measured in cubic meters or gallons per day, significantly influences the overall cost. Plants with higher capacity generally entail higher upfront investments.
• Desalination Technology: Different technologies, such as reverse osmosis (RO), multi-effect distillation (MED), and multi-stage flash distillation (MSF), have varying capital costs. Reverse osmosis costs depend on factors like the type of membranes used. Advancements in desalination technologies, such as improved efficiency and the use of renewable energy, can help lower costs.
• Site Characteristics: The location of the desalination plant, including proximity to the water source, available infrastructure, geological conditions, and environmental considerations, can affect upfront costs. Remote or challenging sites may require additional investment. Decentralized desalination plants built close to the source and point of use offer a cost-effective solution for providing potable water to communities in remote coastal areas and islands.
• Intake and Outfall Systems: The design and construction of intake systems to draw seawater and outfall systems for brine discharge contribute to the initial costs. The choice of methods, such as open ocean intakes or subsurface intakes, can influence expenses.
• Pretreatment and Post-treatment Facilities: Adequate pretreatment facilities are essential to remove impurities that could damage desalination equipment. Post-treatment facilities ensure that the produced water meets quality standards. The complexity of these systems influences costs.
• Labor and Construction Costs: Local labor, construction, and project management fees are important considerations. Construction costs can vary based on labor availability, local regulations, and materials.
• Environmental Compliance: Compliance with environmental regulations and permits may involve additional costs. This includes environmental impact assessments, mitigation measures, and monitoring systems that ensure the project complies with environmental standards.
• Project Financing: The financing structure, such as whether the project is publicly or privately funded, can affect upfront costs. Private financing may involve additional considerations, like return on investment for investors. With Seven Seas Water Group’s Water-as-a-Service® (WaaS®) financing model, no upfront investment is required. The plant is owned and operated by Seven Seas, and customers pay only for the water delivered.

Ongoing Operational Costs

The expenses associated with desalination do not end once the plant has been established. Operational expenses typically include the following:

• Energy Costs: Desalination processes, especially those using technologies like reverse osmosis, are energy-intensive. The cost of electricity or other energy sources required for pumping, pretreatment, and desalination constitutes a significant ongoing expense.
• Maintenance and Repairs: Regular maintenance is essential to ensure the efficient and reliable operation of desalination equipment. This includes maintaining pumps, membranes, valves, and other components. Unforeseen repairs may contribute to ongoing costs.
• Chemicals and Consumables: Desalination plants often require chemicals for pretreatment, cleaning, and maintaining the integrity of membranes. The cost of anti-scalants and cleaning agents is an ongoing operational expense. Consumable items such as membranes, filters, and other components with a limited lifespan will need to be replaced periodically. The frequency of replacement will depend on the type of technology and the quality of the source water.
• Staffing Costs: The salaries of operators, maintenance personnel, and administrative staff must be considered. Skilled operators are crucial for optimizing plant performance.
• Brine Disposal: Responsibly disposing of brine generated during desalination is a continuous operational expense. The method of disposal, whether through deep-well injection, surface water discharge, or other means, can influence costs.
• Water Quality Assurance and Environmental Compliance: Ensuring that the water meets quality standards involves ongoing monitoring, testing, and quality assurance measures. This includes the cost of testing equipment, personnel training, laboratory facilities and analysis, and quality control. Desalination facilities must also adhere to environmental regulations. Ongoing expenses include monitoring, compliance reporting, and implementing measures to mitigate environmental impacts.
• Administrative and Overhead Costs: General administrative expenses, office facilities, and overhead costs are ongoing. Costs also must include insurance premiums to cover risks and liabilities associated with operations, as well as any permit fees that may be required for compliance with regulatory requirements.

Water-as-a-Service®: A Cost-Effective Solution

While the operational and maintenance costs of running a desalination plant are quite extensive, Seven Seas’ WaaS® partnerships offer an affordable solution. There are no upfront costs and no ongoing costs. The plant is operated and maintained by Seven Seas at no cost to the customer other than the water supplied.

Seven Seas promotes sustainable water treatment practices that minimize environmental impacts while optimizing long-term cost-efficiency. This is achieved through decentralization, where smaller, localized water treatment facilities are installed near the point of use. This alleviates the need for lengthy distribution pipelines, reducing capital and operating expenditures for pipeline maintenance. It also reduces the environmental impact of an extensive network of water pipes. Decentralized water treatment plants are more sustainable and more environmentally friendly.

Desalination as a Sustainable Solution

With nearly three-quarters of the Earth’s surface covered by water, this endless supply offers a viable solution to water scarcity challenges. While the cost of reverse osmosis seawater desalination may seem high, it offers a reliable and cost-effective option for improving water security compared to thermal desalination, which requires a heat source and is far more energy-intensive and expensive.

When paired with sustainable water treatment technologies and the innovative WaaS® financing model that Seven Seas offers, desalination is a viable and sustainable solution for water scarcity. Contact Seven Seas to learn more about our cost-effective and environmentally friendly solutions.

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