Improving clean energy greenhouse heating with solar thermal energy storage and phase change materials

Abstract

Greenhouses consume a great deal of energy to heat their building envelopes.The strategic integration of solar energy and thermal energy storage (TES) can help to boost energy performance and reduce the carbon emission in the sector. In this paper, the benefits of adding phase change materials (PCM) to the water tank of a solar heating system have been evaluated using the Transient System Simulation (TRNSYS) program. Initially, the hourly heating load of a reference greenhouse was evaluated using TRNSYS software. The results were validated with natural gas consumption data. The validated simulation was then used to investigate the impact of PCM on the performance of a large-scale solar energy system. Four system configurations were evaluated; no PCM materials in the tank, then 20%, 40%, and 60% of the water tank volume occupied by PCM. Energy performance improvements of 10% to 14% were observed by increasing the proportion of PCM amounts over the baseline conventional system. Finally, an economic study was conducted to investigate the cost feasibility of different PCM concentrations. It was shown that PCM price, cost of natural gas, and carbon tax are the principal influence factors on the payback period. K E Y W O R D Sgreenhouse, phase change material (PCM), solar heating system

Review on solar collector systems integrated with phase‐change material thermal storage technology and their residential applications

“…4 For the phase-change material (PCM) used in the construction field, the latent heat is released through the phase change process of the PCM, thereby improving the indoor temperature comfort and ultimately achieving energy saving effects. 5,6 Because PCM releases high latent heat during phase change, many countries use PCM to store thermal energy. 2 Solar heat collection systems generally include solar heat collectors and energy storage tanks, which are also energy storage heat exchangers, some solar systems may not have energy storage tanks.…”

“…Thermal energy storage (TES) can not only meet the needs of electricity and space heating, they also help to eliminate the fluctuation of energy demand and alleviate the intermittent problems of solar thermal energy at different times throughout the day 4 . For the phase‐change material (PCM) used in the construction field, the latent heat is released through the phase change process of the PCM, thereby improving the indoor temperature comfort and ultimately achieving energy saving effects 5,6 . Because PCM releases high latent heat during phase change, many countries use PCM to store thermal energy 2 .…”