energy consumption is very high in greenhouses mainly due to off-season production. the main source of its energy supply is fossil fuels. due to the disadvantages of fossil fuels consumption and preventive laws in the incoming years, study on reducing consumption and replacing a part of them with renewable energy is essential. in this research, a solar heating system, equipped with a concentrat...

Using PC-based on-line monitoring system, extensive measurements were performed in insulation blocks cut from the crosslinked polyethylene (XLPE) insulation of 36, 69 and 132 kV rated cables produced in Saudi Arabia. A needle-plane electrode system was used with a needle radius of 10 m. The role of 'applied voltage step-time duration' and associated time resolved initiation and growth of diffe...

This paper describes the aging behavior of the oil impregnated repulped cellulose and compares it with the aging behavior of the oil impregnated standard cellulose. In order to evaluate the reliability of using repulped cellulose in transformers, the accelerated aging process was applied to both types of cellulose by increasing the temperature to 150 °C and their aging behavior was studied and ...

This paper has the purpose to investigate HVDC insulation design considering real operating conditions, when DC steady-state is affected by frequent voltage transients or load variations that may be present during all life. Electrical field distribution in insulation, and defects, change significantly from vary with time, which can cause partial discharge activity often not been properly accoun...

Bioresources are used in different production systems as materials as well as energy carriers. The same is true for fossil fuel resources. This study explored whether preferential resource usages exist, using a building insulation system as an example, with regard to the following sustainability criteria: climate impact, land, and fossil fuel demand. We considered the complete life cycle in a l...

High voltage transmission has been chosen in electric power system due to its capability to transfer a large amount of electric power. Several key equipments such as generator, transformer, GIS, cable and insulator play important role in determining the reliability of the power system. The high voltage equipments in general contain gas, liquid or solid insulation. Defects and a particular condi...

In Slovakia, 35% of buildings are older than 50 years but most newer buildings built before 1990 have greater energy consumption. Some other countries also have similar problems. The growing importance of energy saving in buildings can be, in the case of new and old residential buildings (RB), achieved by lowering thermal energy consumption most often by application of polystyrene insulation on...

Transformers are one of the most critical and essential components of electricity transmission and distribution. The life of a transformer is determined by the life of its paper insulation and transformer oil. To maximize the lifetime and efficiency of transformers, it is essential to be aware of possible faults that may occur and to know how to prevent them. One of the major faults in transfor...