Benchmarking studies

Benchmarking of Acceptable Indoor Environment

Brief:

This study established energy benchmarking models that related the major acceptable indoor parameters to building energy consumption. Field surveys of 293 workers and 125 residents were conducted to evaluate the probable preferences of occupants towards IEQ, and the likely indoor environments of general air-conditioned offices and dwellings. The results indicated that thermal comfort was the most prevalent problem occurred in both types of building. Based on the probable indoor environments investigated, benchmarking models for the energy consumption of ventilation systems in air-conditioned offices and the energy utilization of residential buildings were studied. For some Hong Kong offices, ventilation system is characterized to be the most significant component in annual energy consumption. The results showed that the energy consumed by a ventilation system would be correlated closely with the carbon dioxide (CO₂) concentration in the space, but its correlation with the air temperature set point would be less significant. While for the residential sector, simple normalization with a single parameter might not be good enough for assessing energy consumption performance and complicated benchmarking model imposed difficulties for adaptation in general public. Therefore, a simple sustainability benchmark using a five-star rating system, without inclusive physical measurement, for residential buildings was proposed. It was found that both the water and fuel-gas consumptions have significant correlations with the occupant load in an apartment, whereas neither the occupant load nor occupancy factor showed close correlation with the electricity utilization of the apartment. The sustainability benchmark, by considering the electricity and fuel-gas consumptions, scores the most sustainable household with “5 stars” for its low energy consumption.

This work is part of a master dissertation. Student: L.Y. Law (MEng)

Related topics:

Star weight system

Related Publications:

Mui KW, Wong LT, Law LY, 2007. An energy benchmarking model for ventilation systems of air-conditioned offices in sub-tropical climates, Applied Energy 84(1) 89-98.

Wong LT, Mui KW, Law LY, 2007. A benchmarking study for apartment water consumptions in Hong Kong, International Journal for Housing Science and Its Applications 31(2) 129-136.

Mui KW, Wong LT, Law LY, 2007. Domestic water consumption benchmark development for Hong Kong, Building Services Engineering Research and Technology 28(4) 329-335.

Wong LT, Mui KW, Law LY, 2009. An energy consumption benchmarking system for residential buildings in Hong Kong, Building Services Engineering Research and Technology 30(2) 135-142.

Lai ACK, Mui KW, Wong LT, Law LY, 2009. An evaluation model for indoor environmental quality (IEQ) acceptance in residential buildings, Energy and Buildings 41(9) 930-936.

Mui KW, Wong LT, Chan WY, Law LY, 2007. Energy benchmarks for ventilation systems in air-conditioned offices, The 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings, 28-31, Oct, Sendai, Japan. Proceedings Volume 3, pp. 417-423.