Which Is Right for Your Application?

Both cooling towers and adiabatic cooling units perform the same core function:
They utilise the ambient wet bulb temperature to remove heat from a water circuit.

So if they achieve the same result, which solution is right for your site?

The answer depends on duty, footprint, operating costs, and long-term strategy.

1️⃣ Technology Background

Cooling Towers

Cooling towers are the more traditional technology and have been widely used across industrial and HVAC applications for decades. They are typically lower in initial capital cost, especially at higher cooling capacities.

Adiabatic Cooling Units

Adiabatic systems are newer to the market. They were developed largely in response to:

• Rising water treatment costs
• Increasing scrutiny around Legionella control
• Growing environmental and sustainability targets

2️⃣ Capital Cost vs Operating Cost

💧 Water Treatment Costs

Water treatment is one of the biggest differentiators.

• Cooling towers require ongoing water treatment, monitoring, and compliance servicing.
• These costs are particularly significant for systems under 1MW duty.

If your cooling requirement is less than 1MW, the higher initial capital cost of an adiabatic cooler can quickly be offset by avoiding continuous water treatment expenses.

However, when duties exceed 1MW, the lower capital cost of a cooling tower often becomes difficult to ignore — even when factoring in ongoing treatment costs.

3️⃣ Legionella Concerns

There is often hesitation around cooling towers due to Legionella risk.

In reality:

• The cooling tower industry is heavily monitored
• Modern water treatment regimes are robust
• Compliance is tightly regulated

The risk is not the cooling tower itself — it arises only when treatment and servicing are neglected or fall below legal standards.

With proper maintenance, cooling towers operate safely.

4️⃣ Footprint and Space Constraints

If space is limited on site, footprint becomes critical.

In many cases:

• Cooling towers can offer a more compact footprint
• Adiabatic systems can require larger coil and pad surface areas

Where plant space is restricted, this may influence the decision.

5️⃣ Noise Considerations

With modern EC fan technology and inverter-driven motors, both systems can be designed to meet strict noise criteria.

Noise is rarely a deciding factor today — it comes down to correct system design rather than product type.

6️⃣ Corrosive Environments

Both cooling towers and adiabatic coolers can be constructed using:

• Specialist coatings
• Stainless steel
• Corrosion-resistant materials

Long service life can be achieved in aggressive atmospheres with the correct specification.

7️⃣ Running Efficiency

Both technologies are highly efficient at rejecting heat.

Cooling Towers:

• Higher water consumption
• Ongoing treatment costs
• Typically low fan energy per kW rejected

Adiabatic Units:

• Reduced water use
• Lower treatment requirements
• Slightly higher fan energy in some cases

The difference often comes down to total lifecycle cost modelling.

8️⃣ Reliability & Redundancy

Reliability can be designed into either system.

Both cooling towers and adiabatic systems can be configured in:

• N+1
• N+N
• Modular arrangements

This decision lies with the system designer or integrator, not the technology itself.

9️⃣ Temperature & Performance

In high wet-bulb conditions, cooling towers can typically achieve around 1°C lower approach temperatures compared to adiabatic systems.

Aside from this small difference, both technologies perform very similarly.

Correct hydraulic design, pressure considerations, and load matching are more critical than the product choice itself.

Our Overview

If your cooling duty is 300kW or greater, we recommend:

1. Requesting quotations for both cooling tower and adiabatic solutions
2. Obtaining a full water treatment cost proposal for the cooling tower option
3. Comparing:
   • Capital cost
   • 5–10 year operating costs
   • Footprint requirements
   • Site constraints

The right choice is rarely just about equipment price — it’s about total system design and long-term operating strategy.