GREEN BUILDING
In a chilled-water system, the entire air conditioner is installed on the roof
or behind the building. It cools water to between 4.4 and 7.2 degrees
Celsius. The chilled water is then piped throughout the building and
connected to air handlers. Due to the reduction in refrigerants used and
the reduction in electrical costs it is a greener air-conditioning system and
consequently one will achieve an additional 2 to 3 Green Star points.
The advantages of the chilled water system are:
• Very high flexibility
• Very simple to do replacements, a skilled technician is not required to
do tenant changes
• Chilled water can deliver up to 20% energy saving over VRF due to
ability to change parameters for different times of year
• Refrigerant is contained in one component i.e. chiller located on the
roof and requires less volume
• Very few implications of adding units during tenant changes as
against the VRV which is costly
ISSUE 30 - JUNE 2017
So, one asks the question why would one not go for a chilled water
system? Well, that’s simple! It is more expensive with the VRV system
costing about P850/m² against the chilled water system of P1 050/
m². While it seems like a lot of money, when you consider the energy
saving of P5 per month per m², the story changes. The annual saving
of P60/m² per annum against a cost of P200/m² means that there is
a 39-month payback period (which is nothing in the overall scheme of
things), and it is only that long if the electricity tariffs stay at the current
low levels.
Needless to say we are going to be changing to the chilled water
system, getting the extra green building points and saving electricity!
Who can be unhappy with that?
Until the next issue……….
7