No abstract

Research reactors all over the world are expected to operate within certain safety margins just like pressurized water reactors and boiling water reactors. These safety margins mainly include onset of nucleate boiling ratio (ONBR), departure from nucleate boiling ratio (DNBR), and flow instability ratio (FIR) in addition to the maximum clad or fuel temperature and saturation temperature or boing point of the coolant inside the core of the reactor. This study carried out steady-state safety analysis of the Ghana Research Reactor-1 (GHARR-1) with low enriched uranium (LEU) core. Monte Carlo N-particle (MCNP) code was used to obtain radial and axial power peaking factors used as inputs in the preparation of the input file of plate temperature code of Argonne National Laboratory (PLTEMP/ANL code), which was then used to obtain the mentioned safety parameters of GHARR-1 with LEU core in this study. The data obtained on the ONBR were used to obtain the initiation of nucleate boiling boundary data with respect to the active length of the reactor core for various reactor powers. The obtained results for LEU core were also compared with that of the high enriched uranium (HEU) core. The results obtained show that the 34 kW GHARR-1 with LEU core is safe to operate just as the previous 30 kW HEU core was safe to operate.

Energy is essential for economic development and improvement of quality of life in every human settlement. Considering her economic aspirations and population growth, Ghana’s energy demand, particularly that of electricity is sure to rise in coming years. Ghana’s total installed electricity generation capacity currently stands at 1810MW, with a current population is estimated to be 24.4 million based on 2010 population census. The country and for that matter is confronted with the challenge of meeting her energy needs in a cost effective and environmentally friendly manner so as to attain middle income status. This policy document presents nuclear power as the most versatile, convenient and competitive source of electrical energy that should be planned for now and will be worth introducing into Ghana’s energy mix for sustainable development of the country.  Nuclear Power Plants can serve as a competitive source of electrical energy for enhancing Ghana’s energy security and socio-economic development for her to attain middle income as purported by political policies.

DOI: http://dx.doi.org/10.5755/j01.erem.60.2.1109

The National Nuclear Research Institute of the Ghana Atomic Energy Commission is undertaking steps to convert the Ghana Research Reactor-1 from HEU Core to LEU. The proposed LEU core consists of 12.5% enriched UO 2 fuel elements clad in Zircaloy-4 alloy. This is done in collaboration with Reduced Enrichment for Research and Test Reactor. The versatile MCNP code was used to analyse the neutronics parameters given in the SAR of HEU core, thereby characterizing the core. Subsequently, the LEU core was indentified with necessary changes to the HEU MCNP model. It was ascertained that the reactivity for the LEU core with the same number of fuel pins as the HEU was inadequate, hence the fuel pins were increased from 344 to 348. The neutron flux at the irradiation sites was found to be below the nominal value at full power for the LEU and hence the nominal power was increased to 34 kW for a nominal flux value of 1 × 10 12 n/cm 2 •s. The parameters investigated for the HEU and LEU are shown in this paper.