Atmospheric Vortex Engine

Frequently Asked Questions


4. Cooling Towers

4.1 What is a cooling tower?

A cooling tower is a device for transferring waste heat from a power plant to the atmosphere. Once through cooling is only available near large bodies of water.  Once through cooling is sometimes objectionable for environmental reasons because returning warm water to a body of water can have adverse effects on marine life.

4.2 What types of cooling towers are used?

There are many types of cooling towers. The major types are wet and dry cooling towers. Wet cooling tower are more cost effective than dry cooling tower because of the high efficiency of direct heat contact between water and air. In a wet cooling tower, the cooled water can approach the wet bulb temperature of the air. In a dry cooling tower the cooled water temperature can only approach the dry bulb temperature of the air. The condenser temperature achievable with a wet cooling tower can be 20°C lower than that achievable with a dry cooling tower resulting in a significant improvement in plant performance. The ultimate source of cooling in a wet cooling tower is evaporation of water into the air. About 4% of the water circulated is evaporated each time it goes though the tower, therefore wet cooling towers require a large make-up water supply. Dry cooling towers can be the only alternative where water is not available. Wet cooling type cooling towers are predominant. There are many types of wet cooling towers:

  • Crossflow towers
  • Counterflow towers
  • Mechanical towers
    • Induced draft towers
    • Forced draft towers
  • Natural draft towers
  • Fan assisted natural draft towers
  • Combinations of the above

Natural Draft Cooling Tower

Crossflow Cooling Tower

Mechanical cooling towers need fans to drive the air flow through the water. The power required to drive the fan can be 2% of the electrical output of a power plant. In addition another 2% may be required to circulate the water through the cooling tower. Natural draft cooling towers do not require fans, but natural draft cooling towers need to be very high (200 m) to produce sufficient draft and are 3 to 4 times as expensive compared to forced draft cooling towers. Natural draft cooling towers are only economical for very large power plants with large cooling requirements.

Dry cooling is much less efficient than wet cooling and is only used where water is not available. Dry cooling requires more fan power and does not achieve as low cooling water temperatures compared to wet cooling towers. A dry cooling system can use a closed water circuit where water is cooled in finned tubes or can condense the steam directly in the finned tubes. Additional information on cooling towers can be found at: SPX Cooling Technologies 4.3 How are cooling towers relevant to the Atmospheric Vortex Engine?

Cooling towers are commonly used to transfer heat from thermal power plants or other industrial processes to the atmosphere.  Using the waste heat stream intended for a cooling tower to generate a controlled vortex offers the potential of extracting additional energy by rejecting the heat to the much colder upper troposphere (more on this in section 7 of the FAQ).

Wherever there is an existing cooling tower or other abundant low-temperature heat source, there is potential to use the waste heat as fuel for an atmospheric vortex engine.

The diagram below illustrates the essential elements of a cooling tower and also shows the similarities in heat transfer compared to a naturally occurring waterspout.

At the base of a natural waterspout, spray from warm sea water transfers sensible and latent heat to the rising air column.  Proven, existing technology from the cooling tower industry can replicate the heat transfer conditions which exist at the base of a naturally occurring waterspout.  Some additional modifications (tangential air inlet ducts) are required to cause the air to rise with a spinning motion.

Only relatively minor modifications to existing cooling tower designs would be required in order to convert a cooling tower into an atmospheric vortex engine.

Higher resolution version of the above figure - PNG (484 KB)