The technologies available today make it possible to find chillers that manage to simultaneously control hot and cold water.
by Alfredo Sotolongo*
The most economical energy to produce is the one that is saved!
A few months ago I concentrated on modular compact chillers and their myriad technical and economic advantages. However, it is important to mention other applications that represent great energy savings.
Many consulting engineers have selected modular compact chillers in facilities where the use of hot water is necessary and energy savings must be maximized. This represents considerable savings in energy consumption in cases where hot water is generated through electric heaters and even when the energy to heat water comes from gas.
These chillers supply these three combinations: cold water only, hot water only or simultaneously hot and cold water. The high value of COP ensures lower operating costs, faster return on investment and a smaller carbon footprint. They produce the maximum possible heat since they use the total heat and not the overheat heat only. The extra unused heat is removed through the air-cooled exchanger.
They are composed of:
a) Scroll compressors and each module includes two compressors.
b) Heat exchanger from coolant to hot water.
c) Coolant to cold water heat exchanger.
d) Refrigerant-to-air heat exchanger to remove unused extra heat.
e) Electronic expansion valve.
f) Reversible valve.
(g) Control system.
During the cooling process in air conditioning systems, heat is generated and is normally wasted into the atmosphere, either through the cooling tower or the condenser coil. This practice has been around since refrigeration began to be used and there are many negative factors related to the waste of heat to the atmosphere.
Most buildings require some heat to control humidity, drinking hot water and other hot water needs, even in mid-summer in our tropical areas. Heat recovery is responsible for avoiding the waste of heat into the atmosphere, improving the efficiency of the building, reducing the carbon footprint and minimizing the cost of energy.
As I indicated in the previous writing about modular compact chillers, the company Multistack has invested great economic and human resources to develop equipment that recovers the heat that was previously wasted towards the atmosphere. The concept of heat recovery has existed since the early 1970s, but it was complicated to implement since chillers were very large and the temperature of the water they produced was limited. The modular compact chiller concept developed by Multistack changed the application from very complicated to very simple as it managed to simultaneously control hot and cold water, especially when the chiller can supply water up to 180⁰F.
Experience tells us that when a building needs both cooling and heating, the benefits achieved with these modular compact chillers justify the investment. This applies to both existing projects and new buildings.
To colleagues attending the ASHRAE fair in Atlanta, I recommend that you visit the Multistack exhibition in space number C6853 to personally confirm the benefits of these equipment.
If you need more information on any of the topics covered in this column, please contact me at the mail: [email protected]
