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An agrivoltaic system is a combination of solar power generation and crop production that has the potential to increase the value of land. The system was carried out at a 25-kW photovoltaic (PV) power plant located at the Asian Development College for Community Economy and Technology (adiCET), Chiang Mai Rajabhat University, Thailand. The growth and yield of bok choy (Brassica rapa subsp. chinensis L.) and the solar power output were investigated and compared with the control. Moreover, the efficiency of the agrivoltaic system was evaluated. The results indicated that the average intensity of solar radiation of 569 W/m2 was obtained. The highest power generation was recorded in the PV with crop production of 2.28 kW. Furthermore, the control plot of crop production at 35 days provided higher growth than bok choy plots under solar panels of 2.1 cm in plant height, 6 in leaf number, 2.2 cm in leaf length and 0.2 cm in leaf wide. High-yield of bok choy was also obtained in the control plot of 17.31 kg. Although the yield of bok choy is extremely low, possibly because of light intensity, crop cultivation under solar panels could reduce the module temperature to less than the PV control of 0.18 °C, resulting in increased voltage and power generation by around 0.09 %. Therefore, an agrivoltaic system is another option for increasing revenue and land equivalent ratio in solar power plants focusing only on electricity generation. However, suitable crops for the space under PV panels should be investigated further.

This work focuses on the design of the household biomass gas stove which is suitable for the lifestyle of the Thai northern people. In addition, the performance and exhaust emission of the stove - updraft gasifier - was design per the community requirement were evaluated. The stove consists of a combustion chamber – a primary chamber - and a secondary chamber with the primary and secondary air inlet of 0.016 and 0.002 m2, respectively. Moreover, the flow rate of primary air and secondary air was 0.456 and 1.340 kg/s, respectively. The performance of the stove was analyzed by the water boiling test technique and the emission of exhaust gas was evaluated with a fuel gas analyzer. The result indicated that the thermal efficiency of the stove was 44.84%. The specific fuel consumption was 0.029 kg/kg of water. Comparing the designed stove with the traditional clay brazier stove, the performance of the designed stove was higher than the traditional stove. The emission comparison between the designed household biomass gas stove, the traditional stove and the Thai exhaust gas emission standard indicated that both stoves released NOx and SO2 which are less than the standard whereas CO emission of the designed stove conformed to the standard. This work confirmed that the efficiency and the exhaust gas emission of the designed stove are better than the traditional stove. Therefore, this household biomass gas stove could replace the conventional stove

The ground-mounted solar farms are the most common type of Thailand solar power plant. Presently, the area under the solar panels in Thailand had not been utilized. This work was to investigate a suitable configuration for space utilization under the PV panels which could promote power production. The effect of space utilization was investigated for 3 configurations: a water pond, chili cultivation, and a grass plantation. Under the first PV string, the pond sizing 2.4 × 15 meter was created. Under the 2nd PV string, 60 chilies samples were planted. Moreover, the grass was planted under the third string. The intensity of solar radiation (W/m2), temperature, voltage and current of solar panels were also monitoring. The impact of all configurations on the power generation was evaluated and compared with a control.  Results indicated that the space utilization of the first string (the pond) and of the second string (the chili cultivation) generated electricity at 1.6 kW. Both configurations could generate more power than control. The pond and the vegetable plantation were suitable configurations for promoting power production.