Linear receiver characterization - Measurement of heat loss, cermet-reflectance and glass-transmittance of linear solar receiver tubes
Electricity is the most valuable energy,
To be obtained from solar energy with good performance, requires the establishment of a system of accumulation of high temperature heat
During periods in which the heat absorbed is not sufficient to cover the demand, it can integrate generation using fossil fuels (oil and natural gas)
Energy absorption is obtained by concentrating solar energy with an optical system, the concentrator reflects the radiation on the surface of the receiver, where heat is absorbed in the form
ENEA has chosen the collectors parabolico-lineari, characterised by the fact that the reflecting surface follows the trajectory of the sun at rotation on only one axle.
The efficiency of this technology to produce high-temperature heat optical concentrator depends on the performance and the conversion efficiency of the receiver, who should be able to absorb as much energy as possible, with the minimum heat losses by radiation in the environment outside.
The maximum temperature of the tube receiver operation depends essentially on the heat transfer fluid that is used. The choice of the mixture of salt is:
60 % 40 %kno Nano 3, 3.
The system for accumulation foresees two tanks for the storage of heat transfer fluid: One hot and one cold at 550 °C above the temperature at 290 °C (solidification of salts).
The project thermomechanical tube receiver ENEA provides a maximum temperature of the heat transfer fluid to 550 °C, which corresponds to a maximum temperature of the surface of the steel tube of approximately 580 °C
A material and selective spectrally fototermici with these parameters:
Efficient solar absorbance photo-thermal power generation, namely high (> 94 %) and low emissivity (< 14 %) up to 580 °C;• tempera-tura high chemical stability and structural temperature up to 580 °C
The use of a low-cost concentrator an air receiver and innovative in order to focus and accumulate in an efficient way.
The presence of a heat storage system for a 1gw capable of effectively offset the variability of solar energy
The receiver shall consist of:
— a steel tube within which circulates the fluid and which is deposited on a surface with a high coefficient of selective absorption of solar radiation;
— an outer casing formed from a transparent borosilicate glass tube with anti-reflective treatment, two joints and two metal bellows vetro-metallo clearing of differential thermal expansion between glass and steel
In regions of the world with high solar power density, typically the tropical belt, the use of this source of energy produces annually, for each
M² floor area, the same amount of thermal energy combustion
One barrel of oil, avoiding losses of approximately 500 kg of
Carbon dioxide.
companies interested in the manufacturing of the concerned components.