An absorption chiller is an energy-efficient alternative to traditional mechanical refrigeration systems. Unlike conventional chillers that rely on electric-driven compressors, absorption chillers use heat energy to drive the cooling process. This makes them ideal for industries looking to reduce energy costs and improve sustainability.
These systems are commonly powered by waste heat, natural gas, or solar energy, making them a low-emission solution for cooling applications. Absorption chillers are widely used in commercial buildings, industrial facilities, and district cooling systems, where they provide consistent, large-scale cooling without high electricity demand.
Understanding how absorption chillers work, their key components, and their applications can help businesses decide if this energy-efficient refrigeration technology is the right fit for their operations. As a leading refrigeration company, we specialise in designing and maintaining innovative cooling solutions that prioritise efficiency and sustainability.
Key Components of an Absorption Chiller
Absorption chillers rely on a heat-driven cooling cycle, using a specialised set of components to transfer and remove heat efficiently. Unlike traditional chillers, they don’t use a compressor. Instead, they utilise a heat source and chemical absorption process to achieve cooling.
- Heat Source – Provides the thermal energy required to drive the absorption cycle. This can come from waste heat, natural gas, or solar energy.
- Refrigerant-Absorbent Pair – Most absorption chillers use water as the refrigerant and lithium bromide as the absorbent, though some systems use ammonia-water for low-temperature applications.
- Evaporator – The refrigerant absorbs heat from the cooling load, turning into a vapour.
- Absorber – The refrigerant vapour is dissolved into the absorbent, generating a heat reaction.
- Generator – Heat is applied to separate the refrigerant from the absorbent, restarting the cycle.
- Condenser – The refrigerant condenses back into a liquid, ready for another cooling cycle.
Each of these components plays a vital role in ensuring stable, energy-efficient cooling, making absorption chillers a key innovation in sustainable refrigeration.
How Does an Absorption Chiller Work?
Absorption chillers operate using heat energy instead of mechanical compression to drive the refrigeration cycle. The process follows a four-stage absorption cycle, ensuring efficient heat transfer and cooling.
- Evaporation – The refrigerant (typically water) absorbs heat from the cooling load and evaporates into a vapour, lowering the temperature in the system.
- Absorption – The refrigerant vapour is drawn into the absorber, where it is dissolved into the lithium bromide solution (or ammonia in some systems). This process releases heat, which is removed by a secondary cooling loop.
- Regeneration (Desorption) – Heat is applied to the generator, separating the refrigerant from the absorbent. The refrigerant turns back into a vapour, while the absorbent solution is recirculated.
- Condensation – The refrigerant vapour enters the condenser, where it cools and returns to liquid form, ready to start the cycle again.
This closed-loop process allows absorption chillers to provide consistent cooling while using low-carbon energy sources like waste heat or renewables, making them ideal for energy-efficient applications.
Applications of Absorption Chillers in Commercial and Industrial Settings
Absorption chillers are widely used in large-scale cooling applications, particularly where waste heat, natural gas, or renewable energy can be utilised for efficiency. Their low electricity demand and ability to run on alternative heat sources make them a key solution for businesses focused on sustainability and cost-effective cooling.
- District Cooling Systems – Used in commercial buildings, hospitals, and campuses to provide centralised cooling with minimal energy consumption.
- Industrial Manufacturing – Found in chemical plants, metal processing, and food production, where waste heat from industrial processes can be repurposed for cooling.
- Hotels & Hospitality – Reduces operational costs by utilising waste heat from boilers or cogeneration systems to provide air conditioning.
- Data Centres & IT Facilities – Helps maintain stable temperatures in critical infrastructure without adding to peak electricity demand.
With their versatility and energy-efficient operation, absorption chillers are a key component in modern refrigeration and cooling strategies.
Is an Absorption Chiller the Right Cooling Solution for Your Business?
Absorption chillers offer a low-carbon, energy-efficient alternative to traditional cooling systems. Their ability to operate on waste heat, natural gas, or renewables makes them ideal for businesses looking to reduce energy costs and improve sustainability.
For facilities with excess heat sources, such as industrial plants, hotels, and district cooling systems, absorption chillers provide a cost-effective cooling solution without relying heavily on electricity. However, they require careful system design and regular maintenance to operate efficiently.
As a leading refrigeration company, we design and maintain tailored cooling solutions that align with energy efficiency goals and regulatory standards. If you’re considering an upgrade, our experts can assess your requirements and recommend the best system for your needs. Learn more about innovative cooling technologies, including CO₂ refrigeration systems, to future-proof your operations.
