Experimental and numerical optimization on chilled water configuration for improving temperature performance and economic viability of a centralized chiller plant

Abstract

This research aimed to simulate and optimize chilled water circuit system of a central air conditioning plant applied for a five-star hotel in Bali Island, Indonesia. This optimization was performed because temperature of chilled water distributed to the loading system could not satisfy room temperature requirement. Detailed measurements have been taken on the AC system included refrigeration system of the chillers, chilled water and cooling water distribution, cooling load, heat rejection and pumping systems. Thermodynamic analyses on the system energy performance were carried out. Numerical simulations were also established to evaluate chilled water flow rate in the primary and secondary circuits. The measurement and simulation results showed there was unbalanced chilled water flow rate between primary and secondary circuits and the chilled water flow rate did not comply with rule of flow ‘primary flow must always be equal to or greater than secondary flow’ resulted in the cooling load coils lost their cooling capability. Optimization on the chilled water flow rate between primary and secondary circuits by implementing variable speed pumping system incorporated balancing valve was estimated to be potentially improve temperature performance and economic viability of the chiller plant operation.

Eco-Efficiency and Energy Audit to Improve Environmental Performance: An Empirical Study of Hotels in Bali-Indonesia

“…If the hotel, which has the main activity of providing room services, food and beverage, and accommodation services, ignores environmental performance, the hotel will become a source of pollution and environmental damage (Asadi et al, 2020;Pereira-moliner et al, 2021). For example, the hotel industry's excessive use of groundwater (over-pumping) results in a water deficit and causes land subsidence, which triggers flooding (Lo et al, 2021;Suamir et al, 2020). Hotels are big players in energy consumption and consistently rank among the highest energy consumers in the tertiary building sector, which is focused on service delivery (Peng et al, 2017).…”

Analisis perbandingan berbagai sistem AC komersial pada aplikasi gedung hotel

“…Di antara utilitas bangunan, peningkatan penggunaan energi sistem pemanas, ventilasi, dan AC atau lebih dikenal dengan HVAC menjadi sangat signifikan [11]. Beberapa solusi telah diusulkan untuk mempromosikan konservasi energi seperti pengembangan sistem AC yang dilengkapi dengan sistem heat recovery untuk memanaskan air [12][13][14][15][16]; menjaga kinerja sistem melalui pemantauan ketat pada parameter kunci chiller termasuk temperatur approach evaporator dan kondensor [17]; dan mengoptimalkan distribusi sistem sirkulasi air dingin [18]. Hal ini dapat mendorong penerapan efisiensi energi yang lebih luas, untuk mendukung komitmen Pemerintah Indonesia dalam mengurangi emisi Gas Rumah Kaca (GRK) sebesar 26% pada tahun 2020 [19].…”

Increasing performance of chiller systems in high-rise buildings by load optimization

“…Then, it was optimized by a genetic algorithm (GA) based to find the optimum solution to obtain the minimum power consumption of the chiller. Wang and Meng et al investigated the experimental and numerical optimization of chilled water configuration to provide better cooling performance and reduce energy consumption [13]. Huang and Zuo proposed a new method for optimizing chiller sequencing control [14].…”