cooling towers

Three Key Considerations When Using Water as a Heat Transfer Medium

Water (H2O), the most abundant substance on earth, is also a universal solvent.  From rivers and lakes to seas and oceans, water is the main ingredient but its composition varies because of its solvent properties. As water falls through the air, it absorbs gases and picks up particulates such as dust and pollen. Then, as it trickles down through soil and rocks, it dissolves minerals along the way. As a result, water quality varies greatly both regionally and seasonally.

cooling towers

Water vapor rises from cooling towers at power plants, hospitals, hotels and other large facilities.

Water is also a highly effective heat transfer medium. Heat transfer is the process whereby thermal energy or heat moves from one body or substance to another, and from hot to cold. We’ve all noticed the large plumes rising from a hospital, hotel or a power plant. 

water air cooled

Water versus Air Cooled Chillers: Which is Best for Power Plants?

Fabrication of a modular chiller plant

To call water a hot commodity is an understatement.  From controversial water trading to desalination, a slew of efforts are underway to solve water scarcity issues in many regions of the world.  Some, like the massive undertaking by Israel to reuse wastewater and desalinate water from the Mediterranean Sea, are having an impact.  But as population and urbanization continues to grow worldwide, so does water consumption, and, naturally energy use.

Water and energy are closely tied. Consider that thermoelectric power plants – which currently provide the vast majority of US electricity — consume a lot of water.  In fact, the power industry is one of the largest water users in the United States.

Presently, in the US, coal plants are being displaced by natural gas plants.  However, gas turbine efficiency is the lowest when the demand for power is the highest, during hot summer months. To offset this negative effect of high ambient temperature, gas turbine inlet air can be cooled via mechanical chillers.