Water Conservation is a Pressing Matter
Recent political and regulatory trends have proven that conservation of resources and varieties of “green solutions” will continue to be pressing issues not only on a global scale, but also even in affluent regions in the United States. With that in mind, AWeb Supply’s GeoExchange solutions promise an environmentally friendly, eco-smart alternative to traditional cooling towers and HVAC systems.
The Basic Operation of a Cooling Tower
A cooling tower is used to reduce the temperature of warmed water by extracting energy from warmed water and emitting this energy to the atmosphere through evaporation. The graphic below shows a cooling tower’s use of evaporation, whereby some of the water is evaporated into a moving air stream. Drift is subsequently discharged into the atmosphere. Treatment chemicals are used to control the concentration of dissolved solids in the blowdown that is discharged from the cooling tower, adding to water consumption.
A cooling tower with 100 tons of cooling capacity uses/evaporates 252 gallons of potable water per hour. This calculates out to be 6,000 gallons of potable water per day, 184,000 gallons of potable water per month, or 2.2 million gallons of potable water consumption per year. Replacing this type of cooling tower with a closed loop GeoExchange system could conserve 2.2 million gallons of potable water on an annual basis. Expanding on this for every 1,000 tons of cooling capacity conserved the consumption of potable water could be reduced by 22.1 million gallons annually.
When an adequate body of water is available, the Slim Jim or Geo Lake Plate is an excellent alternative to a cooling tower.
Adding GeoExchange as a heat source produces all seasons’ savings when used with a Heat-Pump, reversible chiller or water cooled equipment. It is easy to install, labor friendly, maintenance free, and a relatively small footprint are just some of the benefits. It is important to note with GeoExchange, there is no media to change, no blow-down chemicals and no desalination is required for seawater or brackish water applications. But the two most important things are (1) Zero Emissions and (2) is Environmental Friendly!
AWeb Supply’s GeoExchange solutions, comprised of a Slim Jim® or Geo Lake Plate®, is an environmentally friendly, eco-smart alternative to the traditional cooling tower and HVAC system.
Cooling Tower (Closed Circuit) vs. GeoExchange (Closed Loop) – 100 Tons of Cooling
In this presentation we will use a 100 ton cooling tower with a capacity of 1,500,000 Btus per hour, running at 100% at 3.5 cycles. The 2015 utility costs are from the published information form the “City of Los Angeles Depart of Water and Power” and the “Department of Public Works Bureau of Sanitation”. Electrical power cost is 20.5¢ per kilowatt per hour. Potable water cost is $7.35 per 1,000 gallons. Waste water cost is $5.31 per 1,000 gallons. The chemicals need to maintain 100 ppm in the cooling towers blowdown is $2.00 per pound.
Cooling Tower (Closed Circuit) vs. GeoExchange (Closed Loop) Potable Water Operating Comparison
Based on the information from the previous slide we can see the cooling tower consumes 4.2 gallons of potable water per minute. This calculates out to 2.2 million gallons of potable water consumption on an annual basis. Out of this 2.2 million gallons, 1.5 million gallons of potable water is lost in evaporation and 631,000 gallons of potable water goes down the drain.
Cooling Tower (Closed Circuit) vs. GeoExchange (Closed Loop) 100 Tons of Cooling
This slide shows the comparison between the annual potable water consumption per 100 tons of cooling of a cooling tower and a GeoExchange system. The cooling tower consumes 2.2 million gallons of potable water compared to the GeoExchange potable water consumption of 0 gallons.
It is important to note a GeoExchange (Closed Loop) system requires no potable water consumption for operation. The closed loop water is constantly recycled. There is no evaporation, no blow down and no chemicals. Potable water is only needed during the initial fill of the system.
Additional Water Savings through Energy Reduction with GeoExchange (100 Tons of Cooling)
In this slide, the graph on the left shows the energy consumption for the cooling tower to be 43,800 kilowatt hours per year. This breaks down to 37,500 kilowatt hours per year to run the fans and 6,300 kilowatt hours per year to run the pump. The energy consumption for our GeoExchange system is only 6,300 kilowatt hours per year to run the pump. This reduces energy consumption by 37,500 kilowatt hours per year.
Now let’s take it a step farther. It takes an average of 2 gallons of potable water to produce 1 kilowatt hour of electricity. The graph on the right compares the amount of potable water consumed for electric power production for each system for the same period. The cooling tower consumes 87,600 gallons of potable water for electrical power production. The GeoExchange system consumes 12,500 gallons of potable water for electrical power production.
With GeoExchange the result is an additional potable water savings of 75,100 gallons per year.
Additional Benefits of GeoExchange using Slim Jim® / Geo Lake Plate®
Adding GeoExchange as a heat source produces all seasons’ savings when used with a Heat-Pump, reversible chiller or water cooled equipment. When an adequate body of water is available an excellent alternative to a cooling tower is Slim Jim or Geo Lake Plate. It is easy to install, labor friendly, maintenance free, and a relatively small footprint are just some of the benefits. It is important to note with GeoExchange, there is no media to change, no blow-down chemicals and no desalination is required for seawater or brackish water applications. The two most important things are zero emissions and it is environmental friendly.
Variety of Applications for GeoExchange using Slim Jim® / Geo Lake Plate®
There are endless non-potable water applications for GeoExchange using the Slim Jim or Geo Lake Plate. Some of these include gray water treatment lagoons, rain/storm water retention areas, sewer treatment, water treatment, manufacturing supply/discharge use, dual use of irrigation system, saltwater applications – remember, no desalination, and the list goes on.
Whenever there is an adequate body of water to utilize, there is opportunity to save potable water and energy.
