Review on recent development micro gas turbine -trigeneration system and photovoltaic based hybrid energy system

Research on distributed power generation as an alternative method to the conventional power generation system continue to be developed to improve its commercialization capabilities. The cogeneration system and trigeneration system are technological improved alternatives in distributed generation where they offer enhancement and reliability in term of efficiency, emission performances and economic benefits. However, it is more feasible to implement the trigeneration system for most commercial and domestic distributed generations as the cooling demand is deliberately high compared to heating demand especially in hot and humid climate locations. Moreover, micro gas turbine is observed to be a beneficial prime mover in cogeneration and trigeneration system based on several criteria such as ability on acquiring high heat to power ratio characteristic as well as lower greenhouse gas emission. On the other hand, the role photovoltaic in building integrated system provides opportunities for renewable energy system engagement in trigeneration based distributed generation systems. This paper emphasize on summarizing the research work perform on cogeneration system or trigeneration system in hybrid mode with photovoltaic. There are also preceding sections on overviewing the state of art of cogeneration system and the trigeneration system as well as photovoltaic technologies in power generation

Experimental study on performance of square tube absorber with phase change material

The intermittent nature of solar radiation has decreased the performance efficiency of solar heaters. Integrating the solar heater with thermal energy storage component could increase its performance effectively. In this article, an investigation on the effect of phase change material (PCM) as the thermal energy storage component on the performance of square aluminum tube was carried out experimentally. In the first phase, the temperature behavior of square aluminum tube with two types of PCM, namely, generic plant-based PCM (A2) and paraffin wax (A3), was compared with square aluminum tube without PCM (A1). In the second phase, the performance of square aluminum tube was investigated with different paraffin wax masses of 38 g (B1), 48 g (B2), and 58 g (B3). Based on the result, the A3 tube configuration performed better than A1 and A2 tube configurations with higher heat gain rate (0.08°C/s) and lower heat discharge rate (−0.04°C/s). The B2 tube configuration was found to have maximum heat gain of 3.73 kJ with higher heat discharge rate as compared with other square tube configurations. The average temperature difference between internal and external surface tube of B2 was lower (4.3°C) leading to higher average temperature difference at ambient temperature of 25.3°C. Instantaneous efficiency of the tube B2 is higher than the B1 and B3 tube configurations by 16% and 26%, respectively. The result suggests that the insertion of paraffin wax inside the square absorber tube improves the temperature response of the absorber in the situation of intermittent solar radiation

Performance evaluation of solar collectors using a solar simulator

Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved

Performance of force circulation cross-matrix absorber solar heater integrated with latent heat energy storage material

The utilization of thermal energy storage in the thermal absorber applications has been increasingly important especially in the application where there is a mismatch between energy demand and energy supply. This technology implies that the heat is stored during charging or discharging process through melting and freezing of the thermal energy storage material so that it can be used in the future. This paper presents the outcome of the experimental investigation on the performance of cross-matrix absorber (CMA) utilizing paraffin as the thermal energy storage material. Experiments were carried out by exposing the CMA under different artificial solar radiation (300 W/m2, 500 W/m2, 700 W/m2 and 900 W/m2) for 30 minutes followed by 30 minutes of discharging process. Based on the observation, it was found that smaller mass flow rate value of 0.005 kg/s gave the highest temperature output regardless of the intensity of solar radiation as compared to the other after 30 minutes of charging process. In terms of heat gain by the thermal absorber, it was concluded that the highest mass flow rate of 0.01 kg/s passing through the absorber lead to the higher heat gain by the CMA, hence prolonged the cooling down / discharging period as shows by the result, where case with maximum mass flow rate (0.01 kg/s) consistently contributed to the higher heat gain by the absorber. This feature is very useful in the solar thermal collector related applications such as crop drying and domestic building heating. The heat gain by the absorber is also contributed by the intensity of the solar radiation

Thermal absorber material selection for solar thermal Bi‐Metallic multilayer crosses absorber

The energy gain term determines the level of energy received by the solar absorber from solar radiation and various methods have been implemented to increase the collector performance using a bi-metallic cross absorber. Experiments have been conducted to determine suitable material pairing between the bi-metallic cross absorber and black coated flat-plate absorber. Five types of solar thermal absorbers are investigated under condition 525 W/m2 of solar radiation and with 0.52 m/s air flow speed in terms of heating and cooling performance. Four set stainless steel cross absorbers achieved best energy retention capability by obtaining the slope value of -0.1520 during the cooling phase while during the heating phase, coated flat plate performed well with a slope value of 0.4909. The profile of the thermal absorber with thermal absorption and thermal buffer can be summarized using a spider chart with distance index bar-chart, and the result shows that a bi-metallic, aluminium and stainless steel cross absorber exhibit the optimal balanced thermal profile. With the implementation of the material selection method could minimize the material selection process for cross absorber application

A performance and technoeconomic study of different geometrical designs of compact single-pass cross-matrix solar air collector with square-tube absorbers

This manuscript presents a performance study on a forced convection single-pass solar air heater channel with compact cross-matrix absorber (CMA) incorporating metal hollow square-tube absorbers. Four different geometries of CMA (Type I, II, III and IV) were investigated experimentally to evaluate their efficiency, pressure drops and heat transfer parameters. The experiments were conducted with uniform heat flux (indoor) and outdoor solar radiation as heat source. The air mass flow rates used were between 0.0142 kg/s and 0.0360 kg/s. Techno-economic feasibility studies were conducted using cost-benefit ratio (AC/AEG) method. Thermal efficiency of the CMA obtained by Type I with 76%, being the highest. CMA Type I also exhibited the highest temperature elevation than other configurations with 15.3 °C and thermal capacity of 38.7 kJ. Maximum pressure drop obtained was 1.33 Pa in turbulent condition with Reynolds number of 50,794. Type I has the advantage of high performance CMA and has comparatively lower cost-benefit ratio (AC/AEG) of 0.15 RM/kWh than other type of thermal absorbers. © 2018 Elsevier Lt

Experimental study on performance of square tube absorber with phase change material

The intermittent nature of solar radiation has decreased the performance efficiency of solar heaters. Integrating the solar heater with thermal energy storage component could increase its performance effectively. In this article, an investigation on the effect of phase change material (PCM) as the thermal energy storage component on the performance of square aluminum tube was carried out experimentally. In the first phase, the temperature behavior of square aluminum tube with two types of PCM, namely, generic plant‐based PCM (A2) and paraffin wax (A3), was compared with square aluminum tube without PCM (A1). In the second phase, the performance of square aluminum tube was investigated with different paraffin wax masses of 38 g (B1), 48 g (B2), and 58 g (B3). Based on the result, the A3 tube configuration performed better than A1 and A2 tube configurations with higher heat gain rate (0.08°C/s) and lower heat discharge rate (−0.04°C/s). The B2 tube configuration was found to have maximum heat gain of 3.73 kJ with higher heat discharge rate as compared with other square tube configurations. The average temperature difference between internal and external surface tube of B2 was lower (4.3°C) leading to higher average temperature difference at ambient temperature of 25.3°C. Instantaneous efficiency of the tube B2 is higher than the B1 and B3 tube configurations by 16% and 26%, respectively. The result suggests that the insertion of paraffin wax inside the square absorber tube improves the temperature response of the absorber in the situation of intermittent solar radiation

Evaluation on methods in estimating the photovoltaic performances affected by module operation temperature in tropical region

This research work is intended to evaluate the reliability of commonly utilized empirical correlations of module operation temperature in estimating the photovoltaic performances in tropical region. The Nominal Operation Cell Temperature (NOCT) model, Tropical Field Operation Cell Temperature (tFOCT) model and the experimental back module temperature were selected for evaluation purposes. The models were evaluated by comparing the performance characteristics of a 250W monocrystalline photovoltaic module installed at University Malaysia Pahang. The monocrystalline back module temperature and power output as well as the environmental data including both solar irradiation and ambient temperature were monitored to assist the analysis. Based on the 5 consecutive day experimental data, results indicated that the module operation temperature estimated by tFOCT model had the closest value to the experimental back module temperature. Whereas, the temperature estimated by NOCT model showed the highest deviation up to 25.8% from the experimental back module temperature. However, in terms of estimating the photovoltaic module power output, the NOCT model had the closest value to the experimentally measured power output. The results also indicated that utilizing the back module temperature often mislead the estimation of photovoltaic module power output. In addition, the deviation of estimated power output from NOCT model, tFOCT model and back module operation temperature as compared to the experimental power output were 15.4%, 18.87% and 21.2%, respectively. Thus, the NOCT model demonstrated better estimation of power output as compared to the experimental result than tFOCT model, and back module temperature. However, better estimation method for tropical regions is still needed because three methods evaluated in this study shows deviation of more than 15.4% from the measured power output

Comparative study on thermal performance of cross-matrix absorber solar collector with series and parallel configurations

This paper presents an experimental study comprising two CMA solar collectors with parallel and series arrangements on a forced convection solar drying system. The parallel and series solar collectors were investigated to evaluate the arrangement type’s effect on the thermal performance. The experiments were conducted using artificial solar radiation that varies from 300 to 900W/m2 with the air velocity of 0.5–2 m/s. The arrangement’s efficiency was evaluated based on the drying chamber’s thermal delivery from the collectors, thermal gains, and drying efficiencies, including air velocity effect and pressure drop. Results show that the solar collectors’ parallel arrangement leads to higher air temperature inside the drying chamber than the series by 3.87 ◦C. The thermal efficiency of 33.89% is achieved for the parallel setup than the series of 27.73%. The series arrangement is superior to the parallel in terms of the pressure drop across the solar drying system. Drying efficiency is observed at a higher air velocity of 2 m/s for both arrangements than lower airflow of 0.5 and 1 m/s. Parallel configuration showed promising performance in drying efficiency and low energy usage compared to the series arrangement in which the negative impact of higher pressure-drop was compensated

Performance analysis of flat plate base-thermal cell absorber (FPBTCA): low thickness design

Research to improve flat plate solar collector performance such as design and material used continuously developed. This paper's objective is to analyze the performance of the thermal cell absorber attached to a flat plate absorber collector (FPBTCA) through a low thickness design. It will produce a lightweight and portable collector application with efficient temperature conversion duration and has energy storage ability. Stainless steel and aluminum materials with different thicknesses use as thermal cell absorbers then aluminum materials use as a flat plate absorber base-collector. The experiment performs using a solar simulator with solar radiation of 700 W/m2. Referring to the results in term of heat storage (Qstorage), the heat transfer rate of the collector (Q ̇) and efficiency of the collector shows that stainless steel 1.0 mm with an aluminum base absorber (Case E) has a higher value which is 412 kJ, 18.21 kW, and 47.08 %, respectively. The higher total energy gain collected at the bottom plate as dummy load in the drying chamber (T1 and T2) is stainless steel 1.0 mm with an aluminum absorber base-collector (Case E) value of 2.85 kJ. Stainless steel 1.0 mm with an aluminum absorber base-collector (Case E) has the maximum value of energy gain at 300 seconds which is 116.08 J for the bottom plate (T1 and Ta). Flat plate base absorber thermal cell (FPBTCA CASE E) shows better performance in thermal storage than Flat Plate Solar Collector (FPSC)