The Brayton cycle's heat source can be obtained from solar energy instead of the combustion of fuel. The irreversibilities of the open and direct solar thermal Brayton cycle with recuperator are mainly due to heat transfer across a finite temperature difference and fluid friction, which limit...

The small-scale open and direct solar thermal Brayton cycle with recuperator has several advantages, including low cost, low operation and maintenance costs and it is highly recommended. The main disadvantages of this cycle are the pressure losses in the recuperator and receiver, turbomachine...

This study details the numerical modelling and optimization of natural convection heat suppression in a solar cavity receiver with plate fins. The use of plate fins attached to the inner aperture surface is presented as a possible low cost means of suppressing natural convection heat loss in a...

The present study considers the design, performance analysis and optimization of a downhole coaxial heat exchanger for an enhanced geothermal system (EGS). The optimum mass flow rate of the geothermal fluid for minimum pumping power and maximum extracted heat energy was determined. In addition,...

Many studies have been published on the performance and optimisation of the Brayton cycle and solar thermal Brayton cycle showing the potential, merits and challenges of this technology. Solar thermal Brayton systems have potential to be used as power plants in many sun-drenched countries. It...

This study was undertaken to compare the economic viability in Johannesburg, R.S.A., of vertical ground-source and air-source systems. Capital costs and optimum borehole length of the ground system were determined. Monthly heating and cooling capacities, and COPs were evaluated to determine...

Hot water consumption in traditional houses in the developing communities of Johannesburg is determined by means of measurements over a period of one year. The consumption per person per day is presented for the different months of a year. Also, hourly hot water consumption per person per day is...

A wind–pv–diesel hybrid power system has been designed for a village in Saudi Arabia which is presently powered by a diesel power plant consisting of eight diesel generating sets of 1,120 kW each. The study found a wind–pv–diesel hybrid power system with 35% renewable energy...

The energy-utilization over a 10-year period (1994-2003) has been analysed for the South African industrial sector, which consumes more primary energy than any other sector of the economy. Four principal sub-sectors, namely iron and steel, chemical and petrochemical, mining and quarrying, and...