Applications of Solar Energy

APPLICATION OF SOLAR ENERGY

TOPIC:- SOLAR THERMAL POWER PLANTS

PREPARED BY:-KARTIK THAKKAR

WEBSITE:- http://steps2learning.blogspot.com

TYPES OF SOLAR THERMAL POWER PLANTS OBJECTIVE

TO UTILISE SOLAR ENERGY FOR POWER GENERATION

METHODS

LOW TEMPERATURE SOLAR POWER PLANT USING FLAT PLATE COLLECTOR (600-1000)

MEDIUM TEMPERATURE SOLAR POWER PLANT USING CONCENTRATED SOLAR COLLECTORS

(2500 - 4000, 10 - 30 KW)

HIGH TEMPERATURE SOLAR POWER PLANT USING TOWER SYSTEM

(5000 - 7000,50 – 200 KW)

1. LOW TEMPERATURE SOLAR POWER PLANTS

RANGE: 600 TO 1000 C

VERY LOW EFFICIENCY ABOUT 2% TO 3%

FLUIDS HAVING LOW BOILING TEMPERATURE AT ATMOSPHRIC PRESSURE LIKE REFRIGERANT R-11, BUTANE GAS.

(A) LOW TEMPERATURE FLAT PLATE COLLECTOR SOLAR POWER SYSTEM SINCE THE WATER CAN BE ONLY HEATED 800 C IN

FLAT COLLECTORS, THE SYSTEM NEEDS TO USE WORKING FLUID HAVING LOW BOILING TEMP. LIKE A BUTANE GAS.

THE SYSTEM CONSISTS OF AN ARRAY OF FLAT PLATE COLLECTORS AND CIRCULATING PUMP.

THE HEATEDWATER ISCIRCULATED IN A HEAT EXCHANGER CALLED BUTANE BOILER, WHERE IT GENERATES THE BUTANE GAS AT HIGH PRESSURE.

THEBUTANEGAS ISSUPPLIED TOA BUTANE TURBINE TO PRODUCE MECH. POWER DUETO EXPANSION OF BUTANE GAS.

THE VAPOURCOMING OUT OF THE TURBINE IS CONDENSED IN A CONDENSER AND SENT BACK FOR RECIRCULATIION WITH HELP OF BUTANE FEED PUMP.

THE MECHANICAL POWEROUTPUTOF TURBINE IS CONVERTED INTO ELECTRIC POWER BY GENERATOR

THE BUTANE GAS IS SUPPLIED TO A BUTANE TURBINE TO PRODUCE MECH. POWER DUETO EXPANSION OF BUTANE GAS.

THE VAPOUR COMING OUT OF THE TURBINE IS CONDENSED IN A CONDENSER AND SENT BACK FOR RECIRCULATIION WITH HELP OF BUTANE FEED PUMP.

THE MECHANICAL POWER OUTPUT OF TURBINE IS CONVERTED INTO ELECTRIC POWER BY GENERATOR

(B) SOLAR POND ELECTRIC POWER PLANT THE SYSTEM WORKS ON RANKINE CYCLE USING

R-11 AS REFRIGERANT.

THE SYSTEM USES A SOLAR POND FOR COLLECTION AND STORAGE OF SOLAR ENERGY.

THE HEAT OF HOT BRINE SOLUTION FROM SOLAR POND IS USED TO EVAPORATE THE WORKING SUBSTANCE R-11 AT CONSTANT PRESSURE IN THE BOILER.

VAPOUR IS USED TO RUN THE VAPOUR TURBINE TO PRODUCE MECHANICAL POWER WHICH IS UTILIZED TO RUN A GENERATOR TO PRODUCE THE ELECTRICAL POWER.

THE EXHAUST OF TURBINE IS CONDENSED IN THE CONDENSOR AT CONSTANT PRESSURE WITH THE HELP OF COOLING WATER.

THE CONDENSATE IS RETURNED TO THE BOILER BY A PUMP AND CYCLE IS REPEATED AGAIN.

THEY ARE ONLY SUITABLE FOR VERY LOW POWER GENERATION HAVING VERY LOW

EFFICIENCY.

2. MEDIUM TEMPERATURE SOLAR POWER PLANT

RANGE:- 250-400 C

PARABOLIC IN LINE FOCUSSING TYPE COLLECTORS ARE USED AND GENERALLY PREFERRED BECAUSE OF LAW COST AND REQUIRED SUN TRACKING IN ONE PLANE ONLY.

WHERE PARABOLOID CONCENTRATING COLLECTORS HAVING HIGHER COST AND REQIRED SUN TRACKING IN TWO PLANES.

THE SYSETM CONSIST OF LARGE PARABOLIC TROUGH COLLECTORS DUELY INSTALLED SUN TRACKING DEVICE TO COLLECT THE SOLAR RADIATION WHICH IS USED TO HEAT A FLUID.

THE WATER IS EVAPORATED BY HEAT AND CONVERTED INTO STEAM WHICH IS UTILISED TO RUN A TURBINE COUPLED TO ELECTRIC GENERATOR.

THE EXHAUST STEAM OF TURBINE IS CONDENSED IN THE CONDENSER WITH THE HELP OF COLD WATER CIRCULATED IN THE CONDENSER.

THE HOT WATER LEAVING THE CONDENSE4R IS EITHER SENT TO COLLING TOWER OR ITS HEAT ENERGY CAN BE USED AS PROCESSED HEAT IOF THE PLANT IS USED IN THE INDUSTRY.

THIS TYPE OF PLANT GENERALLY WORKS ON RANKINE CYCLE BUT IT CAN ALSO RUN ON BRAYTON USING AIR AS FLUID.

A 30 MW PLANT HAVE BEEN INSTALLED IN RAJASTHAN UNDER THE DEPARTMENT OF NON CONVENTIONAL ENERGY SOURCES.

3. HIGH TEMPERATURE THERMAL POWER PLANTS

CAPACITY: 50 MW - 200 MW

(a) SOLAR THERMAL POWER PLANTS USING DISH COLLECTORS

(b) CENTRAL TOWER RECEIVER POWER PLANT USING HELIOSTATS

(a) SOLAR THERMAL POWER PLANTS USING DISH COLLECTORS

THE SOLAR DISH COLLECTORS RECEIVE SOLAR RADIATION WHICH ARE COLLECTED AT COMMON FOCUSSING POINT.

SMALL VOLUME OF FLUID ARE HEATED TO HIGH TEMPERATURE & HIGH PRESSURE AND THIS HEAT IS UTILISED TO RUN A PRIME MOVER BASED ON THE STIRLING CYCLE.

DUE LIMITATUION OF SIZE AND SMALL QUANTITY OF FLUID DISH TYPE SOLAR POWER PLANTS ARE NOT SUITABLE FOR GENERATION OF POWER BEYOND FEW KW.

THIS TYPE OF POWER PLANT HAS BEEN BUILT AT HYDERABAD WHICH GENERATES 30 KW POWER AT ABOUT 30% EFFICIENCY.

(b) CENTRAL TOWER RECEIVER POWER PLANT USING HELIOSTATS

RANGE:- 600-700 C

IT USES AN ARRAY OF PLANE MIRRORS CALLED HELIOSTATS WHICH ARE INDIVIDUALLY CONTROL AND TRACKED TO REFLECT THE SOLAR RADIATION ON A RECEIVER KEPT ON TOWER OF ABOUT 500m HEIGHT.

PRODUCED STEAM IS SUPPLIED IN A CONVENTIONAL STEAM POWER PLANT COUPLED TO AN ELECRIC GENERATOR TO GENERATE ELECTRIC POWER.

THE PRESENT COST OF POWER GENERATION IS VERY HIGH UPTO 4.6 CRORES/MW.

A PILOT PLANT OF 50KW IS BUILT IN ITALY BUT WE CAN GENERATE POWER UPTO 10 MW.

THANK YOU