Potential depletion of fossil fuel and climate change have globally accelerated the demand in renewable and alternative energy. Most of the Southeast Asian countries have an abundance of biomass sources for the energy sector due to their agriculture-based economy and enormous forest resources. Therefore, the study aimed at highlighting an overview of biomass energy in the Southeast Asia countries to convey the environmental and economic benefits from the available biomass sources in the region. In order to achieve the aim, the study synthesized and evaluated the biomass sources, energy potential, utilization, and management in the region, based on the published research papers, review papers, and country reports. It was found that the major biomass sources in this region were fuelwood, wood residues, rice husk, rice straw, sugarcane residues, oil palm residues, and coconut residues. The total annual quantity of the biomass potential from agriculture and forest sector in the region was estimated at more than 500 million tons per year and equal to over 8000 million gigajoules of total energy potential. In order to implement the sustainable utilization of biomass sources, the study specified the barriers and challenges of biomass utilization in these countries and proposed a sustainable approach of biomass energy, by comparing the way of traditional biomass utilization.

The article focus on heat flow generated by heat points over evaporator in eletrotechnical box. The evaporator consists of horizontal pipes supplemented with vertical ribs to enlarge the heat exchanger surface. This ribs were changed as porous zone for simulation process. The evaporator is located in a hermetically sealed electrotechnical box. Observes the spread of heat in the porous materials and air over evaporator and space inside the electrical box.

The article deals with a numerical simulation of the forced airflow around a evaporator with the finned tubes in the electrotechnical box, by finite volume method in the program ANSYS Workbench. The work contains an analysis of the impact of forced airflow on the evaporator with the various seated the electrical components. The aim of the work is to find out the most effective way of heat dissipation by forced convection from the electrical components in the closed space with lowest pressure loss.

The paper deals with use of LOOP thermosyphon heat pipe to transfer heat from electrotechnical box and describe of construction individual types of LOOP heat pipes. The LOOP heat pipe is very good cooling device which requires no mechanical parts in their design. LOOP heat pipe use only phase change during heat transfer, without a compressor, fan or pump. LOOP heat pipe is more energy saving compared to conventional cooling systems with forced convection. The main advantage of cooling by heat pipe is that electrotechnical box can be hermetically closed (dust -free construction), because dust reduces the lifetime of electrotechnical elements in box. Lifetime of LOOP heat pipe equals to the lifetime of construction material. The paper describes mathematical model of LOOP thermosyphon heat pipe (condenser). Compares selected types of working fluids which are filled with a heat pipe and construction materials of heat pipe.