Comparative Analysis of Combined Heating Systems Involving the Use of Renewable Energy for Greenhouse Heating

Chung-Geon Lee,La-Hoon Cho,Seok-Jun Kim,Dae-Hyun Kim,Sun-Yong Park

doi:10.3390/en14206603

Abstract

The continued use of fossil fuels is contributing to severe environmental pollution and the establishment of an abnormal climate; consequently, alternative renewable energy sources are being actively investigated worldwide. Further, following global trends, numerous countermeasures aimed at improving carbon neutrality, promoting sustainable agriculture, and reducing fossil fuel dependence are being implemented in the Republic of Korea. Therefore, this study was conducted to investigate the application of renewable energies for greenhouse heating in the Republic of Korea. Three hybrid systems, numbered 1–3, were constructed using a pellet boiler, hydrothermal heat pump, and solar heat collection system, respectively. Thereafter, the heating performance, combined heat efficiency, energy consumption per temperature lifting, and energy cost per temperature lifting of the systems were compared. The combined thermal efficiency results showed no significant differences. However, in terms of energy consumption and cost, hybrid system 1 demonstrated 25.7 and 24.1% savings, respectively, compared with the other systems. Moreover, based on economic analysis via the net present value and life cycle cost analysis methods, the system reduced costs by 29.2 and 27.7%, respectively, compared with conventional fossil fuel boilers. Thus, hybrid system 1 was identified as the most economical system.

Highlights

Carbon emissions are a global concern, and countermeasures to combat this issue are being implemented globally
Corresponding to the Variation of Energy Cost with Increasing Temperature whereas hybrid systems 3 and 2 showed higher energy costs at 0.98 and 1.13 USD/h, A comparison the energy cost with shown in Figure 12 respectively
Based on the results of the economic analysis performed using the net present value method, it was difficult to confirm whether the observed dependence on the initial investment cost was large or whether the difference in operating expenses affected the economic feasibility of the systems

Summary

Introduction

Carbon emissions are a global concern, and countermeasures to combat this issue are being implemented globally. Numerous international treaties, such as the United Nations. Most advanced countries have set targets to achieve carbon neutrality by 2050 [1,2,3,4,5,6]. The increased focus on carbon neutrality has prompted extensive research on new and renewable energy technologies. To actively participate in pollution reduction and voluntarily reduce estimated carbon emissions by 37% by 2030, the Republic of Korea (ROK) announced the “2030. The roadmap included fixed targets for greenhouse gas emission reduction for each industrial sector. For the agricultural sector in particular, the target was to reduce total carbon emissions by 1%.

Methods

Results

Conclusion