C. H. Lim

A state of the art review of solar walls: Concepts and applications

Sustainable energy system design offers credible and innovative strategies to overcome environmental energy crises. Solar walls offer feasible technique for the exploitation of directional flow of heat in buildings. This article reviewed state-of-the-art concepts, applications and significance of solar walls for energy savings in buildings. Detailed operational framework of various solar-wall configurations, technology and efficiency as building component was discussed. Need for this sustainable energy design in buildings and constraints associated with their realisation were reported to aid proposed future research work.

A thermal comfort investigation of a facility department of a hospital in hot-humid climate: Correlation between objective and subjective measurements

A field study on assessing thermal comfort has been performed on one of the large-scale hospitals in Malaysia, a country where the climate is classified as hot-humid. The main objective of this study was to examine the comfort criteria by American Society of Heating, Air conditioning & Refrigeration Engineers, US (ASHRAE) standards in hot-humid regions and also to find the correlation between predicted mean vote (PMV) according to Fanger’s theory and thermal sensation vote (TSV) according to occupant votes. Therefore, both objective and subjective data was collected in this hospital, and this study’s results have confirmed that the preferred temperature is not necessarily in compliance with a neutral temperature, and people in hot-humid areas would prefer cooler environment to neutral temperature. In addition, by analyzing linear regression, a strong correlation between PMV and TSV was found while R2 = 0.950, and also the neutral temperature point in this field study was around +0.75 on the seven-point ASHRAE thermal sensation scale.

Design and Modeling of One Refrigeration Ton Solar Assisted Adsorption Air Conditioning System

The modeling of the performance of a one refrigeration ton (RT) solar assisted adsorp-tion air-conditioning refrigeration system using activated carbon fiber/ethanol as theadsorbent/adsorbate pair has been undertaken in this study. The effects of hot water,cooling water, chilled water inlet temperatures, and hot water and chilled water flowrates were taken into consideration in the optimization of the system and in the design ofthe condenser, evaporator, and hot water storage tank. The study includes analysis of theweather data and its effect on both the adsorption system and the cooling load. This isthen followed by estimation of the cooling capacity and coefficient of performance (COP)of the adsorption system as a function of the input parameters. The results of the modelwill be compared to experimental data in a next step. [DOI: 10.1115/1.4027964]Keywords: solar energy, adsorption air conditioning, activated carbon fiber/ethanol,cooling load

Field evaluation of reflective insulation in south east Asia

Abstract The objective of this research was to obtain thermal performance data for reflective insulations in a South East Asia environment. Thermal resistance data (RSI, m2 ⋅ K/W) for reflective insulations are well established from 1-D steady-state tests, but thermal data for reflective insulation in structures like those found in South East Asia are scarce. Data for reflective insulations in South East Asia will add to the worldwide database for this type of energy-conserving material. RSI were obtained from heat flux and temperature data of three identical structures in the same location. One unit did not have insulation above the ceiling, while the second and third units were insulated with reflective insulation with emittance less than 0.05. RSI for the uninsulated test unit varied from 0.37 to 0.40 m2 ⋅ K/W. RSI for a single-sheet reflective insulation (woven foil) varied from 2.15 to 2.26 m2 ⋅ K/W, while bubble-foil insulation varied from 2.69 to 3.09 m2 ⋅ K/W. The range of RSI values resulted from differences in the spacing between the reflective insulation and the roof. In addition, the reflective insulation below the roof lowered attic temperatures by as much as 9.7° C. Reductions in ceiling heat flux of 80 to 90% relative to the uninsulated structure, due to the reflective insulation, were observed.

Energy Saving and Emission Analysis via Lighting Retrofitting in a Large-Scale Hospital: Case Study in Malaysia

A field study on energy efficiency by lighting retrofitting has been carried out in one of the large-scale hospitals in Malaysia. The main objectives of this study were to find energy and cost savings after light-emitting diode (LED) tubes replacement in the hospital as well as the emission reduction and payback period time. The results have showed that, by applying this strategy, the energy cost saving will be almost US

Review of thermal energy storage for air conditioning systems

2 million after 3 years with more than 5000 t of CO2 reduction per year as well as 2.9 years is resulted as payback period time.