Diapositiva 1

Exergetic and Parametric Study of a Solar Aided Coal-Fired Power Plant

Ing. Daineris Hernandez

Mechanical engineering: Computational Thermo science

Coal-fired Power Plant

Solar-fired Coal-fired Power Plant

Facilities in Power Generation Section

(1) Boiler

(2) Turbine

(3) Condenser

(4) Heat exchanger

Desareator

Facilities in the Solar Field

The coal consumption rate

Fundamental Parameters

Coal used as the fuel for the power plant has the following analysis:

moisture = 9.9%, ash = 23.7%, hydrogen = 3.11%,

nitrogen = 1.01%, sulphur = 2%, oxygen = 2.78%, carbon = 57.5%, LHV = 21,981 kJ/kg.

Results and Discussions

Results and Discussions

Results and Discussions

Effects of the Solar Irradiations

Effects of the Solar Irradiations

Results

1.- coal consumption rates and the CO2 emissions.

2.- the cost of the electricity.

3.- Exergy and energy efficiency (reasons).

4.- exergy and energy destruction distributions.

Effects of Solar Irradiations

1.- with the solar irradiation increasing from 500 W/m2 to 1,100 W/m2, the exergy efficiency of solar field increases from 35.5% to 36.4%.

2.- the energy efficiency of the solar field is almost unchanged with the increment

of solar irradiation.

the energy efficiency, exergy efficiency and coal

consumption decrease with the increase of solar irradiation

Results

Effects of the Load Ratio.

1.- with the increase of load ratio from 30% to 100%, the exergy and energy efficiency increases from 43.3% to 45.6%, from 45.4% to 47.8%.

2.- when the load ratio of the base plant increases from 30% to 100%, the coal consumption rate of the base plant decreases from 270.8 g/kWh to 257.4 g/kWh.

3.- When the load

ratio of the new plant increases from 30% to 100%, the coal consumption rate of the new plant

decreases from 258.8 g/kWh to 243.7 g/kWh.

Conclusions

Ing. Daineris Hernandez

1.- If the new plant is compared with the base plant, the exergy and energy efficiencies of the new plant are lower than those of the base plant compared to the base plant, and the new plant saves about 13.7 g/kWh of coal.

2.- from the aspect of exergy losses (boiler and turbine).

3.- From the aspect of energy losses(condenser- boiler and condenser turbines).

4.- When the load ratio of the unit is 100%, (i.e., with output of 600 MW), the solar irradiation differs from 500 W/m2 to 1,100 W/m2, the coal consumption rate reduces from 248.8 g/kWh to 241.6 g/kWh, saving coal from 8.6 g/kWh to 15.8 g/kWh.

5.- When the solar irradiation is kept 925 W/m2 unchanged, the load ratio of the unit changes from 30% to 100%, the coal consumption rate of the base plant decreases.

6.- When the load ratio of the new plant increases from 30% to 100%, the coal consumption rate of the new plant decreases.

Papers.

Exergy Analysis of Flat Plate Solar Collectors.

Authors: Zhong Ge, Huitao Wang, Hua Wang, Songyuan Zhangand Xin Guan.

Published: 9 May 2014.

Some Literature:

Zhai, R.R.; Zhu, Y.; Yang, Y.P.; Tan, K.Y.; Eric, H. Exergetic and Parametric Study of a Solar Aided Coal-Fired Power Plant.Entropy2013,15, 10141034. [Google Scholar]

Fahad, A.A.; Ibrahim, D.; Feridum, H. Exergy modeling of a new solar driven trigeneration system.Sol. Energ2011,85, 22282243. [Google Scholar].

Study purpose:

The main propuse is an exergy analysis model of flat plate collectors, considering non-uniformity in temperature distribution along the absorber plate.

Conclusions:

The Main conclusion for me is the effects of the fluid inlet temperature in the useful exergy rates this mean that with increasing fluid inlet temperature, the exergy rates first increases and then decreases. Thus exist an optimum fluid inlet temperature for obtaining the maximum useful exergy rate. Also depending of the fluid inlet temperature the relationship fluid mass flow rate vs useful exergy rate will be directly proportional or inversely.

Exergetic and Thermoeconomic Analyses of Solar Air Heating Processes Using a Parabolic Trough Collector.

This paper presents a theoretical and practical analysis of the application of the hermoeconomict method based on he first and second law of thermodynamics.

In his conclusions estimated that the heat losses at the surfaces of the reflector and receiver as well as during heat transfer of the useful heat generate that the efficiencies by second law are lower (between 5 and 10 times) than those obtained by the first law. This fact may be ascribed to.

In terms of hermoeconomic shows that the influence of the cost of the prototype (Z value) The Z value for solar collector systems represents the total cost of the process since technology reduces the cost of solar collector equipment, so projects may be profitable.

Papers.