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Thailand has pledged to be carbon neutral by 2050 at the UN Climate Change Conference (COP26). Promoting all-new buildings to be net-zero energy consumption within 2030 is a strategy to achieve the goal. The previous works have revealed that policymakers and related stakeholders’ supportive strategies could significantly contribute to promoting the zero-energy buildings (ZEB) investment. Moreover, another big challenge in improving high-energy-efficient buildings is the high initial cost and uncertainties of the future costs. As far as we know, no studies have investigated an effect of such a change in economic and relevant costs on the financial benefits of the ZEB project in Thailand. Such parameters are a significant barrier to decision-making on ZEB investment. Consequently, the guidance for affordable financial feasibility and supportive measures could significantly promote ZEB projects. This study used sensitivity analysis to assess the variations of future costs, including initial cost, energy price, maintenance & operation cost, interest rate, and discount rate, influencing the project’s NPVs and the global costs of three representative office buildings. The analyses showed that the total cost was strongly sensitive to the investment cost, with a maximum reduction of 15.76% when the investment cost was reduced by 20%. The NPV was significantly influenced by energy price, with the variations ranging from 2.83% to 15.12%. ZEB development in large buildings provided more financial profitability than in small buildings. Finally, the key effective financial parameters and the key persons responsible for supporting financial measures were proposed to promote ZEB project investment in Thailand. The increase in energy prices and the decrease in initial cost, especially the cost of the air-conditioning systems, will increase investment returns. However, such increments in energy price also affect small and low-income enterprises. For future implementations of ZEB, policymakers should investigate suitable measures and financial incentives.

Thailand has pledged to be carbon neutral by 2050 at the UN Climate Change Conference (COP26). Promoting all-new buildings to be net-zero energy consumption within 2030 is a strategy to achieve the goal. The previous works have revealed that policymakers and related stakeholders’ supportive strategies could significantly contribute to promoting the zero-energy buildings (ZEB) investment. Moreover, another big challenge in improving high-energy-efficient buildings is the high initial cost and uncertainties of the future costs. As far as we know, no studies have investigated an effect of such a change in economic and relevant costs on the financial benefits of the ZEB project in Thailand. Such parameters are a significant barrier to decision-making on ZEB investment. Consequently, the guidance for affordable financial feasibility and supportive measures could significantly promote ZEB projects. This study used sensitivity analysis to assess the variations of future costs, including initial cost, energy price, maintenance & operation cost, interest rate, and discount rate, influencing the project’s NPVs and the global costs of three representative office buildings. The analyses showed that the total cost was strongly sensitive to the investment cost, with a maximum reduction of 15.76% when the investment cost was reduced by 20%. The NPV was significantly influenced by energy price, with the variations ranging from 2.83% to 15.12%. ZEB development in large buildings provided more financial profitability than in small buildings. Finally, the key effective financial parameters and the key persons responsible for supporting financial measures were proposed to promote ZEB project investment in Thailand. The increase in energy prices and the decrease in initial cost, especially the cost of the air-conditioning systems, will increase investment returns. However, such increments in energy price also affect small and low-income enterprises. For future implementations of ZEB, policymakers should investigate suitable measures and financial incentives.

In this study, the species transport and functional characteristics of a Proton Exchange Membrane Fuel Cell (PEMFC) using the agglomerate model are carried out. The modeling is two-dimensional and a two-phase flow is provided to separate liquid water and gas inside the fuel cell. The water transfer modeling is carried out using three mechanisms of vapor, liquid water, and dissolved water through the membrane. The entropy generations due to viscous loss, heat transfer, Ohmic losses, mass transfer, and latent heat are obtained. The effects of agglomerate radius, active layer thickness, permeability, and porosity on the current density, species transport, power density, liquid water, temperature distribution, and entropy generation are investigated. The results show that permeability has a significant effect on water management formed in the cathode gas diffusion layer. Also, the total entropy generation is more evident at the low voltages. The findings show that using a smaller agglomerate radius and larger active layer thickness has a better effect on the current density and thus results in higher power density. At 0.7 V, as the agglomerate radius doubles, the current decreases by 41 %. At 0.6 V, however, a 34 % increase in power density is seen in the minimum agglomerate radius.

In this study, the species transport and functional characteristics of a Proton Exchange Membrane Fuel Cell (PEMFC) using the agglomerate model are carried out. The modeling is two-dimensional and a two-phase flow is provided to separate liquid water and gas inside the fuel cell. The water transfer modeling is carried out using three mechanisms of vapor, liquid water, and dissolved water through the membrane. The entropy generations due to viscous loss, heat transfer, Ohmic losses, mass transfer, and latent heat are obtained. The effects of agglomerate radius, active layer thickness, permeability, and porosity on the current density, species transport, power density, liquid water, temperature distribution, and entropy generation are investigated. The results show that permeability has a significant effect on water management formed in the cathode gas diffusion layer. Also, the total entropy generation is more evident at the low voltages. The findings show that using a smaller agglomerate radius and larger active layer thickness has a better effect on the current density and thus results in higher power density. At 0.7 V, as the agglomerate radius doubles, the current decreases by 41 %. At 0.6 V, however, a 34 % increase in power density is seen in the minimum agglomerate radius.

In this study, two polymorphs of bismuth oxide were synthesized via the solution-based route for the aqueous phase glycerol transformation to high valuable compounds with low energy photocatalysis in the presence of hydrogen peroxide as the electron acceptor. The results showed that the hydrogen peroxide was deficient to produce OH•radicals in tetragonal bismuth oxide (β-Bi2O3) photocatalyst because it decomposed very fast to H2O and O2and unoxidized glycerol, resulting in a low glycerol conversion at almost 6.6 times comparing with that of monoclinic bismuth oxide (α-Bi2O3) photocatalyst. Also, more valuable products could be produced with α-Bi2O3 photocatalyst system. In addition, the possible mechanisms of hydrogen peroxide on the low energy photocatalytic performances of both bismuth oxide polymorphs were discussed.

In this study, two polymorphs of bismuth oxide were synthesized via the solution-based route for the aqueous phase glycerol transformation to high valuable compounds with low energy photocatalysis in the presence of hydrogen peroxide as the electron acceptor. The results showed that the hydrogen peroxide was deficient to produce OH•radicals in tetragonal bismuth oxide (β-Bi2O3) photocatalyst because it decomposed very fast to H2O and O2and unoxidized glycerol, resulting in a low glycerol conversion at almost 6.6 times comparing with that of monoclinic bismuth oxide (α-Bi2O3) photocatalyst. Also, more valuable products could be produced with α-Bi2O3 photocatalyst system. In addition, the possible mechanisms of hydrogen peroxide on the low energy photocatalytic performances of both bismuth oxide polymorphs were discussed.

PV power generation challenging in solar intermittency irradiance is a main problem in the system operation. Flexible Power Point Tracking (FPPT) algorithm for a PV and battery energy storage system (BESS) for storing surplus power or supplying lacking power are employed for smoothing the power. In contrast to Maximum Power Point Tracking (MPPT) algorithm that required a large BESS to regulate the dc-link voltage, the proposed FPPT can minimize the utilization of BESS. As a results, the operation of FPPT can reduce for the battery sizing while maintaining the benefit of power regulation under 10% of power ramp-rate. This paper presents a comparison of FPPT and without FPPT applying to the PV system to investigate the performance of the proposed control strategy focusing on the utilization of BESS. The real-time simulation HIL is simulated to verify the effectiveness of the system with an irradiance curve profiles.

PV power generation challenging in solar intermittency irradiance is a main problem in the system operation. Flexible Power Point Tracking (FPPT) algorithm for a PV and battery energy storage system (BESS) for storing surplus power or supplying lacking power are employed for smoothing the power. In contrast to Maximum Power Point Tracking (MPPT) algorithm that required a large BESS to regulate the dc-link voltage, the proposed FPPT can minimize the utilization of BESS. As a results, the operation of FPPT can reduce for the battery sizing while maintaining the benefit of power regulation under 10% of power ramp-rate. This paper presents a comparison of FPPT and without FPPT applying to the PV system to investigate the performance of the proposed control strategy focusing on the utilization of BESS. The real-time simulation HIL is simulated to verify the effectiveness of the system with an irradiance curve profiles.