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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 study conducted the utilization of vegetable residues by an enriched microflora inoculum to produce biohydrogen via anaerobic batch reactor. Dark fermentation processes were carried out with 3 kinds of vegetable residue substrates including broccoli (Brassica oleracea var. italica.), onion (Alium cepa Linn.), and sweet potato (Ipomoea batatas (L.) Lam). Vegetable wastes were pretreated into 2 forms, i.e. mashed and powdered vegetable, prior to the fermentation. The substrate used for the biohydrogen production were vegetable residues and inoculum at the vegetable residues/inoculum ratio of 1:1 (based on TS). The digestion processes were performed under 120 rpm speed of shaking bottle in the incubator with control temperature of 35๐C. In this work, the maximum hydrogen production was achieved by anaerobic digestion at mashed onion with bioreactor inoculum that produced total hydrogen of 424.1 mL H2 with hydrogen yield and hydrogen concentration of 151.67 mL H2/g VSadded and 43.54%, respectively. In addition, the hydrogen production continues took only 7 days for the vegetables blended with the bioreactor inoculum. Finally, it was found that the high potential of degradation of vegetable wastes an enriched microflora in dark fermentation also showed alternative solution to eliminate agricultural wastes to produce green energy.

ASEAN communities seek such resources as technologies and products from other countries to develop solar energy for sustainable development. In response to that, major renewable-utilization advanced countries including China has introduced funds, technology, and products into ASEAN. Despite the fact that China SMEs have a strong willingness to enter ASEAN solar energy market and ASEAN has demanded to develop the solar energy industry, only a few of them have succeeded in operation in the long-run. Introducing renewable energy technology and products from one place to another or bringing them from laboratory into community is not just a process of capital equipment supply from one firm to another but also includes the transfer of skills and know-how for operating and maintaining technology hardware, and knowledge for understanding this technology so that further independent innovation is possible by recipient. The purpose of this research was to determine the dynamic elements for China SMEs entering into the solar energy market of middle-income ASEAN member states. This participatory research collects data from both primary and secondary sources. Primary data sources include a questionnaire for 408 respondents of whom background across government officials, research personnel and industry, and interviews for 24 of them. Secondary data include reports from the Asian Development Bank, ASEAN Centre for Energy and other related documents from ASEAN governments. Data collected from the questionnaire were firstly analyzed through quantitative way: the value of Mean, Standard Error of Mean, Median, Standard Deviation (Std.) and Variance of each element were calculated. Information collected from interviews were then analyzed through the qualitative way. The results showed that policy environment, level of industrial and economic development, people’s willingness to cooperate, correct policy interpretation, capacity building and the presence of a third-party intermediary agency are the determinants of Chinese SME's successful entry to ASEAN renewable energy market. The mature policy environment of the ASEAN, need of industrial upgrading and sound economic development would facilitate the development of renewable energy industry, meanwhile, the strong willingness to cooperate, correct policy interpretation on preferential policies, well capacity building of both cooperative sides and the presence of a third-party intermediary agency would promote the cooperation between Chinese SMEs and relevant partners of ASEAN and the sustainable operation of Chinese SMEs in ASEAN.

This study aims to characterize the combustion of the biomass stove filled with a porous medium for air pre-heating to enhance the biomass decomposition. An equivalence ratio, one of the important parameters for the combustion, was investigated to evaluate the completeness of the combustion process. Thermal efficiency was used as the indicator to reflect the performance of the biomass stove. Which was divided into two parts namely the pre-combustion (PCC) and the combustion chamber (CC). The CC volume was 28 liters for fuel storage, and it was insulated for reducing heat loss. The stove was made of 2 mm steel plate and the porous medium was a round-shape ceramic with a diameter of 10 mm. The boiling test was performed using corn cobs as a single solid fuel to boil water in the vessel. The temperature of the stove was measured using a thermocouple Type-K and a data recorder was used to collect the experimental data. The airflow rate was determined using an airflow meter and the fuel consumption rate was calculated using the aforementioned experimental data. Finally, the designed biomass stove will be demonstrated at the community to simultaneously enhance the community-scale energy and reduce the environmental issues.

Waste management is one of the major problems around the world. Governments and global organizations are starting to pay attention to the amount of waste left behind. Thai government drafted the National policies of waste management to manage waste in sustainable ways. Keudchang Sub-district confronts waste management problems due to the increase in the amount of waste, insufficient area for disposal, roadside and riverside litters, an illegal dump of rubbish in forests, and air pollution from waste incineration. The purposes of this research were to study the amount of waste and waste composition in 8 villages of Keudchang Community (KC), and develop appropriate guidelines of waste management. This participatory research collects data from both primary and secondary sources. Primary data sources include interviews and set up a public hearing stage with stakeholders in KC. Secondary data include a documentary of community context, meeting minutes, and other related documents. Qualitative data were analyzed with the content analysis method. The results showed that the KC produce an average of waste to 4,062.02 kg/day. These wastes could be classified into 4 types including organic waste (45.83%), recycle waste (28.01%), general waste (15.55%), and hazardous waste (10.60%) respectively. An individual person at KC produces an average of waste at 0.98 kg/day. Additionally, the results from conducting a public hearing stage of 8 villages revealed community awareness and solutions for waste management. All people in KC need to sort their wastes properly before disposal in 4 ways. First, organic waste. Each household needs to dig a hole and dump the organic wastes into it. The organic wastes should be managed and separated from other wastes. Second, recycle waste. Various approaches to recycle waste include waste credit bank (WCB), waste volunteer, monthly fee, and self-management. The WCB would be a hub for the communities to make profits and reduce landfill wastes. A waste volunteer would be a volunteer person who buys community wastes and sell them to outsiders. The monthly fee would be an approach where each household pays 70 baht/month to a garbage collector. Self-management would be another approach where households sort out, eliminate, sell, and manage wastes by themselves. Third, general waste. General waste could be divided into 2 groups as profitable waste and community dumping ground. Profitable waste could be sold to WCB or waste stores by each household. Community dumping ground would be an area allocated to all households for waste disposal. All households would not allow to throw garbage or wastes into other areas, but community dumping ground. Finally, hazardous waste. Hazardous waste would need to dispose of carefully in the trash can located at the office of the village headman. The findings from this study suggested setting up a waste management committee (WMC), as well as defining their roles and responsibilities. Local administrative organizations and community leaders also need to support, supervise, and control community waste management for resource-efficient and sustainable societies

An innovative software has been developed to measure and identify energy flow for multiple loads and sources like Grid and or other renewables. Algorithms have been developed to indicate status of energy used within a building unit and the Smart Gird as a whole. The software is developed on the AngularJS bases in the model-view-controller (MVC) platform using PHP language and MySQL is used as database for recording the data. The results of this research can support Electricity Generating Authority of Thailand (EGAT) for future grid planning and can be helpful for adaptive forcasting in connection with the consumption and generation. In the future, this software could be applied to improve the functions of energy management system (EMS) in the homes, buildings, and offices.

Due to the energy conservation concern, smart plug has been widely studied for electrical appliance control. This work presented the development of data transmission in smart plug control system using MySQL database with Message Queuing Telemetry Transport (MQTT) protocol. The experimental study showed the speed of data transmission could be increased even with low internet speed. This work could be applied in using smart plug in the area with limited internet speed and might be beneficial for the rural area.

This work focused on the development of DC smart plug for efficient data monitoring and transmission. The transmitted data were collected from smart plug sensors and user commands, and sent via wireless transmission to the online database. The results revealed that the smart plug could control and provide high speed wireless data transmission with minimal error to and from the appliances. The online media was also developed with the smart plug display the power usage and statistics.

This work is an on-going research to develop a smart farm system with environmental analysis for terrace vegetable farming with web application. The terrace farm is separated into 3 levels of moisture settings according to the type of vegetables that require low, medium or high moisture content. The environmental sensors monitor the moisture in the soil and send the information to the database of the farm server. The processed information from the sensors will be analyzed and then provide the appropriate environmental factors in plant growth. The smart farm can be monitored and controlled by web application. This smart farm is considered low carbon agriculture due to the power usage from the community microgrid of 25 kW PV system.

This paper presents a model simulation of the electric power exchange and the electricity bill for four case-study buildings where three buildings have photovoltaic systems. The data for power demand and power supply which is produce from the photovoltaic system in each building were collected at the School of Renewable Energy Technology (SERT), Naresuan University, Thailand. The data for the power demand were then converted to the load profile curves and calculated for the photovoltaic performance from the solar radiation data. Building load balancing algorithm was developed from the simulation model with the data from load profiles and photovoltaic performances. The results from the overall load balancing algorithm were reported as the net metering and the power status of each building. The load balancing algorithm focused on the initial exchange of power between each building. Then, if higher power demand is required, the power would be from the external source such as the existing utility grid or another building. The result of simulation for four case-study building indicated that under the load balancing algorithm criteria, the buildings could sell 44% (261.99 baht/day) of its power from the photovoltaic system to another building while purchasing 56% (337.92 baht/day) power from the existing utility grid. In the future, this power exchange algorithm could be applied for energy saving and energy efficiency improvement to the homes, buildings, and offices.

Pt/SrTiO3 shows promise as a low temperature hydrocarbon combustion catalyst for automotive applications. In this study, SrTiO3 nanocuboid supports were synthesized using sol-precipitation coupled with hydrothermal synthesis, and platinum was deposited on the nanocuboids with 1, 3, and 5 cycles of atomic layer deposition (ALD). The platinum particles have a highly uniform distribution both before and after reaction testing, and range from 1 to 5 nm in size, depending upon the number of ALD cycles. These materials have a >50 °C lower light-off temperature for propane oxidation than a conventional Pt/Al2O3 catalyst, turn over frequencies up to 3 orders of magnitude higher, and show improved resistance to deactivation. The increased activity is attributed to the stabilization of a Pt/PtO core/shell structure during operating conditions by the strong epitaxy between the Pt and the SrTiO3 support.

Cellobiose hydrolysis into glucose was chosen as a model system for cellulose breakdown to investigate glycosidic bond cleavage. The hydrolysis was enhanced by increased acidity in an inert gas medium, while air-assisted hydrolysis with a neutral solution achieved over 70% glucose yield. Hydrogen peroxide, as a stronger oxidant than air, converted cellobiose to carboxyl compounds, which lowered the glucose selectivity. At 150 °C, the selectivity from cellobiose to glucose was very low on porous γ-Al2O3 supported catalysts, even lower than without a catalyst. When the active metals were prepared on non-porous supports such as spherical alumina (α phase), the overall yield of glucose was dramatically improved at 120 °C. Similar improvements were obtained for another disaccharide model, sucrose, which achieved greater than 90% sucrose conversion with selectivity in excess of 90% at 80 °C.

Platinum atomic layer deposition (ALD) using MeCpPtMe3 was employed to prepare high loadings of uniform-sized, 1−2 nm Pt nanoparticles on high surface area Al2O3, TiO2, and SrTiO3 supports. X-ray absorption fine structure was utilized to monitor the changes in the Pt species during each step of the synthesis. The temperature, precursor exposure time, treatment gas, and number of ALD cycles were found to affect the Pt particle size and density. Lower-temperature MeCpPtMe3 adsorption yielded smaller particles due to reduced thermal decomposition. A 300 °C air treatment of the adsorbed MeCpPtMe3 leads to PtO. In subsequent ALD cycles, the MeCpPtMe3 reduces the PtO to metallic Pt in the ratio of one precursor molecule per PtO. A 200 °C H2 treatment of the adsorbed MeCpPtMe3 leads to the formation of 1−2 nm, metallic Pt nanoparticles. During subsequent ALD cycles, MeCpPtMe3 adsorbs on the support, which, upon reduction, yields additional Pt nanoparticles with a minimal increase in size of the previously formed...

Atomic layer deposition (ALD) palladium films were deposited at 200 °C on various ALD metal oxide surfaces using sequential exposures to Pd(II) hexafluoroacetylacetonate (Pd(hfac)2) and formalin. In situ quartz crystal microbalance measurements as well as ex situ measurements performed on planar substrates revealed that the Pd growth begins with a relatively slow nucleation process and accelerates once an adequate amount of Pd has deposited on the surface. Furthermore, the Pd nucleation is faster on ALD ZnO surfaces compared to ALD Al2O3 surfaces. ALD was utilized to synthesize highly dispersed, uniform Pd nanoparticles (1 to 2 nm in diameter) on ALD ZnO and Al2O3 coated mesoporous silica gel, and the catalytic performances of these samples were compared in the methanol decomposition reaction. The ALD Pd−Al2O3 showed high activity and hydrogen selectivity at relatively low temperatures while the ALD Pd−ZnO showed very low activity as well as quick deactivation. In situ extended X-ray absorption fine struc...

A series of Mo2C and Mo2N supported catalysts have been synthesized using a parallel synthesis and high throughput screening approach. The high surface area Mo2C and Mo2N supports were prepared using temperature programmed reaction methods. Metals including Co, Cu, Fe, Ni, Pd, Pt, Ru, and Sn were impregnated onto these supports using a synthesis system. Methanol steam reforming (MSR) activities and selectivities for these materials were evaluated using a high throughput-screening reactor. The support type, metal type and concentration, and metal precursor type influenced the activity and selectivity patterns. Of more than 400 materials that were synthesized and evaluated, the Pt/Mo2N, Pt–Ni/Mo2N, Pt–Fe/Mo2N, and Pd–Fe/Mo2C catalysts possessed the highest activities. Some of these formulations were more active than a commercial Cu/Zn/Al2O3 catalyst, however, the CO2 selectivities were typically lower. At similar conversions, materials that were highly active were not selective while the less active materials were very selective. Many of the highly active catalysts included noble metals while the highly selective catalysts included base metals.

The Smart Community is a real living model community in the mountainous area that completely uses electricity from PV and distributes with DC microgrid in the range of 260 - 297 VDC. The Smart Community is located at the Chiang Mai World Green City of the Asian Development Institute for Community Economy and Technology (adiCET) in Mae Rim Campus of Chiang Mai Rajabhat University, Thailand. The community is comprised of 6 small houses, an office, a minimart, a coffee shop, a restaurant and an organic farm. All of the devices and appliances in the houses and farm are able to operate on DC microgrid, which include lighting, air conditioner, television, refrigerator, computer, water heater, and water pump. These appliances were modified to be able to use with DC as well as AC systems to increase the flexibility of power usage for the transition toward the DC based community. For the other buildings, both AC and DC grids are integrated in the office, minimart, coffee shop, and restaurant. For example during normal operation of the office, the air condition and lightings used the DC grids, but the copier machine and printers used the AC grid. The adiCET faculties, students, researchers and administrative staff used the Smart Community as the working and living place. Operation of the DC and AC usage as well as the issues occurred from the 4-years development were monitored and recorded.