Through assessment of surface water quality at Siep stream in Di An city, Binh Duong province. Siep Stream is a level 1 tributary that flows into Dong Nai River. Dong Nai River is currently being exploited and used for domestic water supply purposes. Sampling location of Siep stream at the culvert on National Highway 1K from January 2022 to November 2023, through statistical monitoring data compared with QCVN 08-2023/BTNMT (level A) and QCVN 08: 2015/BTNMT (column A2) - National technical regulation on surface water, it shows that the parameters increase or decrease without stable, most tend to increase with about 86.9% COD exceeding the standard 1.0 ÷ 7.8 times, 95.6% SS parameters exceeding the standard 1.8 ÷ 30.4 times, 95.6% N-NH4 number exceeds the standard of 0.16 ÷ 21.8 times, 52.1% of N-NO2 parameters exceed the standard by 0.52 ÷ 8.9 times, 65.2% of P-PO4 parameters exceed the standard by 0.35 ÷ 6.25 times, 91, 3% of Colifrom parameters exceeded the standard of 1.0 ÷ 3.3 times. The WQI (water quality index) results show that the surface water quality of Siep stream is mostly average, this result is not suitable for domestic water supply purposes, there needs to be solutions to improve water quality at the area Siep Stream.

Chau Pha Lake is one of the large reservoirs providing water for domestic, irrigation and production of people in Phu My town, Ba Ria Vung Tau province. This study was conducted to analyze the parameters of pH, temperature, DO, BOD5, COD, N-NH4+, P-PO43-, TSS, turbidity, total Coliform on 16 samples in 2020 and the water quality index calculation WQI. The analysis results show that the water quality of Chau Pha lake in the rainy season is quite good, all parameters reach the limit value A2 according to QCVN 08:2015/BTNMT; however, in the dry season, the values of parameters DO, BOD5, P-PO43, TSS exceed the limit value A2 but not significantly; WQI values fluctuate at a fairly high level from 71 to 92, which is correlated with turbidity, COD, and BOD5 parameters. Thus, the average WQI of the lake reaches 85.4 points, corresponding to level 2 (green) - water used for domestic water supply purposes but needs appropriate treatment measures.

Declining supplies of fossil fuels, increasing population, global industrialization and demand for transportation fuels has triggered an increase in the demand for renewable energy sources. To address such problems most of the green research in the recent years has focused on the development of bioethanol (23 MJ/L) as a substitute to conventional gasoline (34.3 MJ/L) based fuels owing to the similarity in energy density values in addition to several other advantages (American Council on renewable energy, 2010). Second-generation biofuels are derived from lignocellulosic biomass or woody crops, mostly coming from agricultural residues. Extraction of fuel from such biomass is difficult because of their recalcitrant nature (corn stover, rice straw, wheat straw, sugar cane and sweet sorghum). Lignocellulosic fuel has the potential to solve several problems (food competing with fuel) that are currently associated with first generation biofuels. Moreover, lignocellulosic fuels can supply a larger proportion of the global fuel leading to sustainability at lower cost, and with greater environmental benefits (Liz Marsall, 2009). The production of ethanol from the complex sugars in leaves and stalks is a promising strategy to radically broaden the range of possible ethanol feedstock. Keywords: lignocellulose, bioethanol, biomass, pretreatment, hydrolysis, fermentation.

Electric vehicles (EVs) making a significant contribution to the reduction of fossil fuel consumption and CO2 emissions are expected to thrive in Vietnam in the upcoming years/in the near future. However, such vehicles’ energy demand could become a burden on the transmission networks, causing overloads to the electric grid of the nation. Hence, to solve this problem, a solar PV system can be utilized to fulfill the electricity needs in an EV charging station. This article presents the design, simulation and economic analysis of a grid-connected solar power system for an electric charging station at Thu Dau Mot University (TDMU). The photovoltaic (PV) power system is designed to supply energy to the charging station and office building. The study estimates the generated electricity, the efficiency of the PV power system and the ability to reduce CO2 emissions. This paper can be a recommended input for stakeholders to consider using this energy source for charging vehicles.

The current status assessment research of water use and quality of supplied domestic water in Thu Dau Mot city, Binh Duong province, as well as the clean water use situation of the local people. Sampling and assessment of the quality of supplied water at Thu Dau Mot Water supply enterprise. The water treatment process here is strictly conducted to ensure stability, constant pressure, inlet and outlet water flow. The analysis results of physical and chemical parameters of water quality at Thu Dau Mot Water supply enterprise show parameters within the allowable limits of water standards for domestic use QCVN 02: 2009/BYT and domestic water QCVN 01: 2009/BYT. However, during the water treatment process in the rainy season, it is time consuming and costly for the use of many chemicals in the treatment process, as high turbidity and high color temperature, low TDS, low pH, low chloride, high SS, Fe and Mn content changes in the wet season higher than in the dry season. After sampling for analysis and treatment, the output water meets the clean water standard to meet the needs of the people in Thu Dau Mot City and surrounding areas. Keywords: water quality, physical and chemical parameters, water standards, clean water.