Journal of Sustainable Energy

3

Authors: JOIAN R., PETREUȘ D., PALAGHIŢĂ N., HORGOŞ M.

This paper point out some of the experimental determinations that must be made in the achieving of a hidro - wind hybrid system. It highlights the design and implementation of a1 kW ballast resistor and 48 V nickel-chromium wire, with the diameter of 60 three millimeters and connecting cable at the wind turbine by electric panel. Thus, this experimental stand CHHE includes a wind turbine 1 kW, placed on the roof of the Technical University of Cluj Napoca (this place is favorable because the wind has high speeds at great height) and hydro turbine type Pelton 1 kW power. The experimental stand for the study of CHHE hybrid energy system will allow the determination of more experimental conclusive on the impact of the achievement of an energy balance of the physical model.

6

Authors: VASIU I.

Thermal energy demand for district heating in the city of Oradea is supplied at present, almost at whole, by the Cogeneration Thermal Power Plant, based on classical fuels, mainly consisting of low grade coal and natural gas, with a small contribution of the geothermal energy. Geothermal resource at low enthalpy, located within the city area of Oradea, available at an estimated level of 250 GWh/year, exploited at present by 12 production wells, can provide a share of 55 GWh/year for district heating, representing at present about 7 % from the overall thermal demand at the end users inlet. Geothermal energy is delivered by means of 3 main thermal stations, in order to prepare, especially household warm water, but sometimes also secondary agent for space heating, using additionally heat, based on natural gas. At present, in the city area of Oradea, more than 7,000 dwellings are supplied by geothermal stations with warm water and in addition for about 3,400 dwellings is assured simultaneously warm water and space heating. Even if the geothermal energy provides at present only a small part of the overall heating requirement at the city level, nevertheless by increased financial support, in the near future is expected its much more contribution, as an alternative to polluting energy of coal and natural gas.

6

Authors: CLODNIȚCHI R., TANȚĂU A.D.

Romania is one of Europe’s traditional producers of energy from renewable sources. After the regime change 1989 nothing happened in this market until 2008 when the Romanian renewable sector went through a remarkable boom. 5.000 MW new capacities were installed mainly in wind, PV and biomass plants but almost none in biogas plants. There is plenty of substrate available, some of it for free, and the support mechanism is also very generous when it comes to biogenic gas, so how come today there are less than 15 MW installed in biogas capacities? This question lies at the base of our research covering several company intern and extern aspects. This particular article addresses the risks induced by technology vs. the market risks on the basis of a study case from Romania. We analyse the profitability indicators of the first landfill gas recovery facility from Romania which was after implementation less profitable than expected.