Optimising Pumping System Performance in the Water Industry

Innovation in the UK water industry is often associated with new assets, new plant and major infrastructure projects. However, one of the biggest opportunities for improvement lies not in replacement, but in getting more from what is already installed.

With regulatory pressure increasing and customer bills under scrutiny, water companies are required to deliver reliable, sustainable services while reducing operational costs. Modern AMP periods place strong emphasis on innovation, not just in technology, but in how existing assets are used, controlled and optimised.

Rather than defaulting to capital investment, operators are increasingly encouraged to maximise the value of their current infrastructure, improving performance, efficiency and reliability through smarter operation.

Doing More With Less

Water companies face a unique combination of challenges:

Rising expectations around environmental performance
Tight controls on customer billing
Ageing networks and assets
Increased focus on resilience and leakage reduction

At the same time, the sector remains one of the UK’s largest energy users, with pumping, treatment and wastewater management accounting for a significant share of electricity consumption.

The industry has also committed to ambitious carbon reduction targets, including achieving net zero well ahead of many other sectors. Meeting these goals means identifying every possible opportunity to reduce energy use, avoid waste and improve system efficiency.

This is where innovation does not have to mean new, it can mean using existing technology more intelligently.

Variable Speed Drives: An Underused Asset

Variable Speed Drives (VSDs) are already widely used across water and wastewater applications to control pump speed and flow. They have delivered proven savings in both energy and maintenance by replacing fixed-speed operation and mechanical throttling.

However, in many cases, VSDs are used only for basic speed control, while their wider capabilities remain underutilised.

Modern VSDs include a range of built-in functions that allow:

More precise process control
Improved protection of pumps and pipework
Reduced wear and tear
Increased system efficiency
Lower maintenance intervention

When fully utilised, these features can transform performance without the need for major infrastructure change.

Energy Efficiency Through Better Control

Pumping systems are typically sized for worst-case demand yet rarely operate at those conditions for most of the day. Without effective control, this leads to unnecessary energy use.

By applying variable speed control, it is possible to:

Match pump output to real demand
Reduce unnecessary high-pressure operation
Avoid frequent start-stop cycling
Stabilise flow for downstream processes

In many applications, improved control strategies alone can deliver 15–20% improvements in system efficiency.

For example, rather than running pumps at full speed until a tank is full and then switching them off, greater efficiency and reliability can be achieved by pumping more slowly for longer. This:

Reduces energy consumption
Minimises mechanical stress
Improves predictability of batch processes such as chemical dosing
Extends the life of bearings and seals

Reducing Maintenance and Avoiding Blockages

One of the most valuable but often overlooked functions of modern VSDs in the water sector is pump cleaning (anti-ragging).

Blockages and ragging reduce flow, increase power draw and often require costly manual intervention. Pump cleaning functions act before conditions become critical by:

Detecting signs of blockage
Momentarily reversing or jogging the pump
Dislodging debris from the impeller

This:

Restores flow rates automatically
Prevents service disruption
Reduces the need for lifting and manual clearance
Extends pump life
Cuts unplanned maintenance costs

Here, the drive is not improving itself, it is protecting and optimising the pump and the wider system.

Sweating Existing Assets

Innovation is not always about new technology, it is about making assets work harder and better.

Smart VSD functions allow:

Pumps to operate closer to their design point
Maintenance intervals to be extended
System performance to be stabilised
Asset life to be increased

Rather than replacing pumps or pipework, performance gains can often be achieved by improving how existing equipment is controlled and protected.

Reducing Bursts and Interruptions

Pressure management is central to improving network reliability.

Excessive pressure increases:

Leakage
Pipe fatigue
Burst frequency
Energy consumption

By using Variable Speed Drives to control pump speed dynamically, pressure can be reduced during periods of low demand, such as overnight. This:

Lowers stress on ageing pipework
Reduces the likelihood of new leaks forming
Cuts energy use
Minimises the cost of emergency repairs

Even relatively simple control strategies can deliver meaningful savings when applied consistently across multiple pumping stations.

Tackling Leakage Through Control

A significant proportion of leakage occurs as small, background losses that are difficult to detect. These are strongly influenced by system pressure.

A modest reduction in pressure can deliver a disproportionate reduction in leakage. In many cases:

A 20% pressure reduction can cut leakage by up to 50%

Because VSDs directly control pump speed, they provide an effective tool for:

Managing network pressure
Limiting unnecessary over-pumping
Reducing the volume of treated water lost
Avoiding the cost of processing and pumping water that never reaches customers

Lower pressure also means lower energy consumption, creating a dual benefit.

The Importance of Data & Visibility

Better control depends on better understanding. Variable Speed Drives generate valuable operational data, including:

Power consumption
Run hours
Load conditions
Fault history

When this data is used effectively, operators can:

Identify inefficient operation
Detect developing faults early
Validate energy-saving measures
Support regulatory and performance reporting

This turns drives from simple control devices into monitoring tools, supporting better operational and asset management decisions.

Why These Capabilities Are Often Underused

Despite their potential, many VSD functions remain unused because:

Drives are commissioned only for basic speed control
Application knowledge is lost over time
Control strategies are rarely revisited after installation
Focus remains on keeping assets running rather than optimising them

Recognising these barriers is the first step to unlocking additional value from existing systems.

Turning Potential Into Performance

Unlocking the full value of installed drives typically involves:

Reviewing how systems currently operate
Identifying where energy, pressure or reliability losses occur
Updating control strategies
Applying existing drive functions more effectively

This approach allows improvements to be delivered without major capital investment and without compromising service reliability.

For water and wastewater operators under pressure to deliver more with less, optimising existing assets can be one of the fastest routes to improvement.
A practical review of pumping and drive operation can reveal opportunities to improve efficiency, reduce pressure and increase reliability, without building new infrastructure.

Key Takeaways

Innovation does not always require new plant or new infrastructure.

By fully utilising the capabilities of existing Variable Speed Drives, water companies can:

Reduce energy consumption
Improve reliability
Lower maintenance costs
Control pressure more effectively
Reduce leakage
Extend asset life

Through smarter control and better understanding of installed systems, operators may find that much of the innovation they need is already in place, waiting to be unlocked.

Want to understand how much energy you could save?

Complete the form and a member of our team will review your application and advise whether a Variable Speed Drive solution could deliver measurable energy and cost savings.