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Project
is particularly advantageous when repurposing or retrofitting buildings , as the system can easily accommodate changes in room layout or function .
COST SAVINGS While the initial capital investment may be higher than VAV systems , chilled beams offer long-term cost savings . Their energy efficiency , reduced maintenance needs , and longer lifespan result in lower operational and replacement costs over the life of the system .
Overall , chilled beam HVAC systems provide a range of benefits , including energy efficiency , improved comfort , space optimisation , indoor air quality , longevity , environmental sustainability , design flexibility and cost savings . These advantages make chilled beams an attractive option for enhancing building performance and occupant satisfaction .
The chilled beam has a life expectancy of 30 years , which is double that of the conventional variable air volume ( VAV ) type of installation . The chilled beams require less air input , thereby reducing the size of air handling units . Since the air volume required to be cooled has reduced , the chiller size also reduces . The reduced size of the AHU and chiller ; little to no input power ; and high life expectancy of chilled beams yield high savings and meaningful returns for the client .
A cost analysis was conducted to showcase the benefits to the client to justify the capital cost and view the savings on the operational , maintenance and replacement costs . The conventional VAV system faired just under two million rands lower than the chilled beam system . However , at the end of year 15 the client would need to replace the entire VAV system , in contrast to the chilled beam system which would require component replacement . Over a 30-year period , the client would have saved approximately R20-million . The internal rate of return was calculated to be approximately 17 % with the chilled beam installation paying itself off in 15 years .
ENERGY EFFICIENCY CONSIDERATIONS RELATED TO M & E TECHNOLOGY Superior equipment has been used in this project – only the chiller is used to heat the water . The efficiency comes from the radiant energy .
Energy savings with beams : When compared with a traditional HVAC system , chilled beams provide superior energy savings by reducing the reheat by 50 % and reducing annual fan energy 30 to 40 %.
Energy reduction can be primarily derived from reduced reheat and fan energy required to operate the system . In addition to the energy- and cost-saving benefits of a chilled beam system , there are significant space savings with chilled beams with a space reduction of 50 % or more in duct area and supply and return chases , and a 30 to 40 % air handling unit footprint reduction – potentially increasing the usable floor space in a building .
PASSIVE DESIGN INCLUSION AND DESIGN IMPACT The project incorporated passive design strategies to enhance the building ' s energy performance . By analysing the building envelope , measures such as clear window glazing , insulation and shading were implemented to reduce cooling loads . These passive design elements work in conjunction with the active chilled beam system , optimising energy performance and occupant comfort .
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RACA Journal I February 2024 www . refrigerationandaircon . co . za