Page 91 - Hong Kong Green School Guide

3. Green School Guide - 3.3 Energy Saving
Hong Kong Green Building Council 89
Benefits
• Provide heating (hot water) and cooling (air conditioning) in one unit; and
• Compared to conventional electrical/gas water heaters, heat pump water
heaters are more energy efficient and can result in 30-50% energy reduction,
which is equivalent to 0.025 kWh for every litre of hot water. This is the same
as saving the energy of a 25-Watt light blub for operating for one hour.
Issues to Consider
a. Opportunities
• Heat pump water heater can be installed to provide hot water for showers
and air conditioning (cool air).
b. Constraints
• Heat pump water heaters include a hot water storage tank which requires flat
ground and more space for installation.
c. Solutions
• Registered Contractor shall be consulted on space for installation, system
capacity, installation location that can best utilise both heating and cooling,
installation practicality (e.g. electrical and plumbing components);
• Suitable for spaces that require both heating and cooling, such as sports
centres – hot water for showers and air conditioning for activity areas,
swimming pool – heating for pool water and cooling or dehumidification for
ancillary areas; and
• Water temperature must be maintained above 60 OC to prevent Legionnaires’
disease.
d. Professional Help
• Registered Professional Engineer (RPE) – Appendix A (4)
• Registered Contractor – Appendix B (1) (4) & (5)
3.3.7 Heat Pump Water Heaters Applies to NS & ES