Geothermal Seen as Solution to Water Wasting Expensive Commercial Cooling Towers
By Susan Nichol
Worrying that California’s multi-year drought is the “new normal?” It is time to consider a better way for cooling buildings with less waste and far greater sustainability.
One are that can provide a real impact for California’s larger building owners and the professionals who design them can do is cut down on the use of cooling towers that make chilled water for space cooling by harnessing the power of evaporation. At one time when water was cheap and plentiful it appeared to be a fantastic solution, but today water is now neither plentiful nor inexpensive. Cooling towers burn through potable water, they use expensive chemicals, lots of electricity and require expensive regular maintenance to be effective and to prevent downtime. Did you know that with all of these negatives there is another? We mentioned that cooling towers use potable water but they produce wastewater that is not even qualified to pass through treatment plants?
How much wasted water are we talking about?
The metrics of water chilling tower systems (per ton of capacity) are worth mentioning. The Cooling capacity of a cooling tower is 15,000 Btu per hour per chiller ton, but let’s talk water usage. The potable water consumed by a cooling tower does not seem bad when you look at it by the hour. The typical use is 2.52 gallons per hour/per ton, that is 60 gallons per day/per ton, then monthly cooling towers consume 1,840 gallons per ton and annually we are looking at a whopping 22,075 per cooling tower.
Ok so cooling towers are bad, but what else is there?
As the most efficient HVAC equipment on the planet, geothermal heat pumps provide thermal leverage on reduced power demand—using NO NET WATER! The earth is their fulcrum and the refrigerant compression cycle is their lever. And in systems containing both hot and chilled water loops, they can concentrate heat or cool from one to the other during moderate loads, without involving their ground loop or a supplemental cooling tower. Governor Brown’s Executive Order B-26-15 for water reductions of 25% is better served by reductions in cooling tower use.
If you live in Northern California and want to learn more about the benefits and the feasibility of having a geothermal installation for your commercial building or home, contact Cold Craft, Inc. at 408.374.7292.