To buy or not to buy? The compelling case for mobile water services in the power industry

In everyday life, we are familiar with rental- or subscription-based models, whether leasing a car, streaming music or hiring equipment. However, choosing an alternative to ownership is not simply limited to the B2C market, and the mobile water services rental model has been growing over the past 15 years. It has quickly become a more cost-effective and flexible alternative to a fixed water treatment plant in a wide range of industrial situations, and the power industry has much to gain from its adoption. Despite advances in the technology, awareness still lags behind, and mobile water services suppliers are keen to bring companies up to speed.

An evolving solution

A lot has changed since mobile water services were first introduced into the market. Originally, they were simply ion exchange resins mounted inside trailers, which could be transported to a site to provide a temporary supply of high purity water. However, customer needs have diversified, generating a demand for a broader range of available physical and chemical technologies, from pretreatment by clarification and filtration to reverse osmosis, absorption, ultrafiltration and ancillary equipment. Nowadays, a typical mobile plant might consist of two or three containers or skid-mounted systems, which can be assembled in a plug-and-play fashion. A typical set-up involves initial pretreatment by multi-media filtration or granular activated carbon adsorption, followed by reverse osmosis in a second trailer, and subsequent mixed bed ion exchange polishing in a third.

The modular design of many of today’s mobile water services allows a variety of process configurations to be combined, making it possible to treat town mains, borehole, river and reservoir water, and even wastewater resources. The containers’ portability enables them to be positioned to make the best use of the available space, eliminating or reducing the need for building infrastructure to house the equipment. Any number of units can be operated in parallel or in series to provide the required flow rate, and their modularity allows additional components or treatment steps to be added for extra functionality or increased throughput, even if it is only needed for a short period. Storage tanks and pumps can also be provided – together with interconnecting fixed pipework or flexible hoses, water meters and fittings – and mobile generators support a completely standalone set-up. A further, and perhaps the most important, consideration is that these modular units can be easily exchanged over time for the latest, updated technology, ensuring that a company’s water treatment systems remain at the cutting edge and benefit from the most cost-effective, available solution from its mobile water services supplier.

CAPEX considerations

The power industry faces a number of current challenges. Emissions targets, changes in supply and demand, and the awareness that its long-term future lies with renewables, have all made it more difficult to make a strong case for capital investment in traditional fuels. The fall-out of this has been a contraction in the market, forcing the closure of a number of power plants, which has only further increased reluctance to invest in projects where the lifetime and return on investment are uncertain. In the light of this, one of the attractions of mobile water services is their flexibility, as the rental payments can be covered by the operational budget, removing the need to raise capital. Mobile water service suppliers – such as Veolia Water Technologies – are often willing to enter into pay-as-you-go, multi year contracts, which help to improve financial planning thanks to predictable, regular payments.

A common misconception is that renting mobile water services is more expensive in the long run, yet this is rarely the case. A number of organisations are choosing long-term hire in instances where the capital investment in a permanent plant would not pay back over the lifetime of the project. A net present value financial calculation comparing the costs of building and maintaining a new plant versus renting mobile water services over a 10-year period is revealing. While the build may be cheaper in the first couple of years, the service, asset maintenance and parts replacement offered by many mobile water services suppliers relieves the facility of these inevitable costs associated with owning a plant, not to mention asset depreciation. In one particular instance, a European power company wanted to design and build a new water treatment plant, but was struggling to raise the necessary CAPEX. Working in collaboration with Veolia Water Technologies and its Mobile Water Services department, the business opted for long- term rental of a containerised plant, which offered a more cost-effective solution and was readily approved by the business.

Plant start-up

Mobile water services are commonly used during the start-up phase of a new power facility. They can support an increased demand for purified water for applications such as boiler cleans, pipework flushes and steam blowing, which remove construction debris, sand, mill scale, etc, from critical systems, including air cooled condensers or steam turbine lines. This ensures optimal equipment cleanliness, enabling efficient plantoperationfordailypowergeneration. Mobile water services can be brought on site to purify the water for this process and then removed when the water demand resumes to normal operating levels following the commissioning activities.

Emergency and planned downtime

Companies that do not need to upgrade or replace their water treatment systems can still benefit from mobile water services, particularly in the case of emergency or planned downtime. Business continuity is defined as ‘the capability of the organisation to continue delivery of products or services at acceptable predefined levels following a disruptive incident’ (Source: ISO 22301:2012). In short, a company should be able to carry on regardless of any challenges it faces. Once a disaster hits, the clock is ticking and it is imperative that a facility gets back to business as usual as quickly as possible, maintaining its reputation and credibility.

Typical emergency water treatment plant disruptions include defective equipment or controls, failure of the permanent water treatment plant or changes to the raw water supply. A temporary water treatment system can be deployed in an emergency to sustain a continuous supply of treated water for all unanticipated scenarios, such as coping with short-term peak power demands, which are particularly prevalent in some countries. Having a robust plan in times of disaster is critical, and mobile water services are helping companies to respond quickly and effectively when a water-related emergency does arise.

Many power plants and facilities will also need to plan for maintenance of existing water systems, and mobile water services can be brought in to cover equipment servicing, ensuring that production or business processes can continue and avoiding costly downtime. In some instances, a facility needs to cope with seasonal or unexpected changes to its raw water supply. For example, bacterial and algal growth, or increased levels of suspended solids during a period of high rainfall, can lead to reduced throughput and long-term damage to existing equipment.

Awareness is key

The numerous benefits that mobile water services can bring to the power industry are, unfortunately, not as well as known as they could be, making education and awareness a key goal for mobile water services suppliers over the next couple of years. A distinct shift in outlook is necessary to help companies to transition from a procurement to a rental mindset and to fully understand that mobile water services represent a sensible alternative to capital investment. For the power industry in particular, it’s important that this thinking is factored into commissioning and decommissioning plants, as it is not uncommon for these processes to demand more water than originally anticipated. As awareness grows, we can expect to see more mobile water services being implemented throughout the power industry, supporting financial planning, ensuring business continuity and helping to maintain resilient and effective water treatment.