To reduce building sector CO2 emissions, integrating renewable energy and thermal energy storage (TES) into building design is crucial. TES provides a way of storing thermal energy during high renewable energy production for use later during peak energy demand in buildings. The type of thermal energy stored in TES can be divided into three categories: sensible, latent, and sorption/chemical. Unlike sensible TES, latent TES and sorption/chemical TES have not been widely applied; however, they have the advantage of a higher energy density, making them effective for building applications. Most TES research focuses on technical design and rarely addresses its environmental, social, and cost impact. Life cycle assessment (LCA) is an internationally standardized method for evaluating the environmental impacts of any process. Life cycle sustainability assessment (LCSA) is an expansion of LCA, including economic and social sustainability assessments. This paper aims to provide a literature review of the LCA and LCSA of TES, specifically for building applications. Concerning the low technology readiness level (TRL) of several TES systems, the challenges and benefits of conducting LCA for these systems are highlighted. Furthermore, based on published studies on emerging technologies for LCA, a suggested procedure to carry out the LCA of TES with low TRL is presented.

The industrial sector utilizes approximately 40% of global energy consumption. A sizeable amount of waste energy is rejected at low temperatures due to difficulty recovering with existing technologies. Thermochemical heat transformers (THT) can play a role in recovering low-temperature industrial waste heat by storing it during high supply and discharging it on demand at a higher temperature. Thus, THT will enable waste heat reintegration into industrial processes, improving overall energy efficiency and lowering greenhouse gas emissions from the industrial sector. Salt hydrate is a promising thermochemical material (TCM) because it requires a low charging temperature which can be supplied by waste heat. Furthermore, its non-toxic nature allows the implementation of a simpler and less costly open system. Despite extensive research into salt hydrate materials for thermochemical energy storage (TCES) applications, a research gap is identified in their use in THT applications. This paper aims to provide a comprehensive literature review of the advancement of THT applications, particularly for systems employing salt hydrates material. A discussion on existing salt hydrate materials used in the THT prototype will be covered in this paper, including the challenges, opportunities, and suggested future research works related to salt hydrate THT application.

The energy consumption for space cooling is progressively increasing. Integrating renewable energy into space cooling systems is critical for reducing CO2 emissions from the building sector. The salt-based cooling system is an appealing alternative as it can be charged by solar energy. This system is based on the characteristic of endothermic salts, which generate a considerable cooling effect when dissolved in water. A screening test was performed in this work to evaluate the cooling performance of several endothermic salts. Furthermore, a laboratory-scale system was developed to demonstrate the endothermic salt-based thermal storage and cooling generation system. Temperature decreases up to 12.3 °C were observed in the system containing Potassium Chloride salt. The temperature drop was maintained after the system underwent a charging/discharging cycle; however, the cooling period was shortened. The system demonstrated an inherent low efficiency due to the large volume of water required in the discharging phase, demanding a considerable amount of energy to evaporate the water in the charging phase. As a result, the application of this system will be restricted to the usage of low-grade energy during the charging phase.

The purposes of this research are designing the prototype   of DMFC, consist of graphite and aluminium cell stacks and MEA with difference Nafion content. Cell stack has active area of 6.5 cm2, and single serpentine flow field. MEAs were fabricated using Nafion membrane 117 (DuPont), gas diffusion layer (GDL) carbon cloth, and commercial catalysts E-Tek, Pt/C for the cathode side and Pt-Ru/C for the anode. Catalysts loading on the anode are 3 and 4 mgPt-Ru/cm2 and on the cathode is 3 mg/cm2. Dry Nafion content of 20 %-wt and 40 %-wt were used in this experiment. MEA fabrication was done by brush coating and hot pressing. Single cell test conducted to evaluate the performance of DMFC at 70°C with 2M methanol as fuel and air as the oxidant. The results of single cell test showed that cell voltage of 600-750 mV, current density of 100 150 mW/cm2, with maximum power density of 19 mW/cm2 ware achieved. MEA with 40 wt% Nafion content showed the better performance than 20 %-wt with power density 19 mWlcm2 and 6 mW/cm2, respectively. Increasing the catalyst loading from 3 to 4 mgPt-Ru/cm2 improved the power density from 16 to 18 mW/cm2. Keywords: Direct Methanol Fuel Cell, Cel stack, MEA, Nation content. Abstrak Penelitian ini bertujuan untuk merancang sebuah prototipe DMFC dengan cell stack berbahan grafit dan aluminium serta fabrikasi MEA dengan variasi kandungan Nafion. Cell stack memiliki luas aktif 6.5 cm2 dengan flowfield bertipe single serpentine. MEA difabrikasi menggunakan membran Nafion 117 (DuPont), lapisan difusi gas carbon cloth dan katalis komersial E-Tek, Pt/C untuk katoda dan Pt-Ru/Cuntuk anoda. Kandungan katalis adalah 3 dan 4 mgPt-Ru/cm2 pada sisi anoda dan 3 mg/cm2 pada sisi katoda. Kandungan Nafion yang digunakan adalah 20 dan 40 % berat. Fabrikasi MEA dilakukan dengan metode brush coating dan hot pressing. Uji kinerja DMFC dilakukan pada suhu 70°C dengan menggunakan bahan bakar metanal 2M dan udara sebagai oksidan. Hasil uji kinerja DMFC sel tunggal didapatkan potensial sel 600-750 mv densitas arus 100-150 mW/cm serta densitas energi maksimum 19 mW/cm2.  MEA dengan kandun?an Nafion 40 % berat memiliki kinerja yang lebih baik dengan densitas energi 19 mW/cm dibandingkan dengan Nafion 20 % berat sebesar 6 mW/cm2. Kenaikan loading katalis anoda dari 3 menjadi  4 mgPt-Ru/cm2 dapat meningkatkan  densitas  energi dari  16 mW/cm2 menjadi 18 mW/cm2.Kata kunci: Direct Methanol Fuel Cell,Cel stack, MEA, kandungan Nation.