Techno-economic feasibility study of using heat pipe heat exchanger to improve dehumidification in air-handling unit

Document Type : Research Article

Author

Niroo Research Institute

Abstract

Techno-economic feasibility study of using wrap around heat pipe heat exchanger (WAHP) to improve dehumidification in air-handling units (AHU) was carried out. Hot and humid climate conditions of north of Iran were applied. Two types of buildings, i.e. with 100% and 25% fresh air were studied. Coupled calculations of cooling coil and WAHP are presented. Corresponding results were validated with outputs of a software belonged to a reputable WAHP manufacturer. Performances of WAHP-AHU and conventional AHU are compared. For economic analyses, two scenarios are considered; first, WAHP is installed as a part of a brand new AHU in the factory. Second, WAHP is installed as a retrofit on an existing an under-operation AHU. Results show that 5% and 25% of electricity savings are obtained by using WAHP on AHU of buildings with 100% and 25% fresh air, respectively. Also, regardless of energy consumption, the brand new WAHP-AHU is more than 20% cheaper than the conventional AHU. For energy tariffs, there are two perspectives: a consumer perspective (with subsidies) and a governmental perspective (including no subsidy). From the governmental perspective, adding a WAHP to under-operation AHUs is profitable, i.e. an IRR of 45% and a 5 years investment return is achievable.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 55, Issue 3
June 2023
Pages 303-336

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