Water’s Heat Capacity - Nature’s Thermal Battery

Ever wondered why water is such a star in heating and cooling applications? At Engineered Efficiency, we often leverage water’s high specific heat capacity to move and store energy efficiently. 

Water can absorb or release large amounts of heat without drastic temperature changes, which is a major advantage over air. Because of this, water is crucial in processes like pasteurising food products or cooling beer bottles and jars.  

In fact, we’ve even used water systems to gently cool delicate tubes of soup to less than 5°C in a system we design for a client.  A competitor’s solution involved using refrigerated air, which required large volumes of sub-zero air to be passed over the product.  Using water instead meant we could keep the system more compact, and with water operating at just over zero degrees Celsius there was no risk of freezing the product. This ensures consistent temperature control and superior product quality. 

“How much better is water than air?”, I hear you ask.  In a bottle warming system design, the heating water changed in temperature by 5°C.  If you use air with the same temperature change, you need more than four times the mass flow, but also nearly 4000 times the volume flow.  Even if you managed to work out a system where you could have the air change temperature by 50°C to reduce the amount of air you needed, you would still need almost 400 times the volumetric flow…and in this instance the bottle tops would have melted. 

With a narrower temperature operating range, there are also greater opportunities for environmental heating or cooling, and higher cycles of performance from heat pumps. 

At Engineered Efficiency, we design systems that maximise water’s thermal benefits — helping clients achieve better results.