This document summarizes solar water heaters, including their main components, types, and workings. There are two main types: flat plate collector systems and evacuated tube collector systems. Flat plate collectors use absorber plates and tubes to transfer heat from sunlight to water. Evacuated tube collectors use glass tubes with a vacuum between the inner and outer tubes for insulation, and transfer heat via a liquid inside the tubes to the water. Both work via thermosyphon effect, where hot water rises due to lower density. Solar water heaters are renewable, non-polluting, and can provide hot water for homes, businesses and more, but have limitations around storage and output on cloudy days.

1. 1
Solar Water heaters
-Submitted by
N.V.A.S.M.SASTRY
9820010002

2. Topics
covered
• Introduction
• Schematic
• Types
• Evacuated glass tube
• Thermosyphon effect
• Working
• Pro’s and Con’s
• Applications
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3. INTRODUCTION
• One of the popular solar powered equipment
• Uses solar power to heat water
• Installed on terrace,roofs or sunlight available
place.
• To provide hot water for
bathrooms,washing,cleaning etc.
• Two different types are available.
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4. Schematic
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Main components :
Storage tank
Solar collector
Pipes
Non return valves

5. Types of solar
heaters
• Flat plate collector type
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• Main components of flat plate collector type
• Storage tank
• Copper tubes
• Absorber plates
• Transparent plates
• Insulation
• Stand

6. Types of solar
heaters
• Evacuated tube collector type
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• Main components of evacuated
tube collector type
• Storage tank
• Insulation
• Copper tubes
• Copper tube coating
• Evacuated tube
• Alcohol solution
• stand

7. Evacuated
glass tube
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The evacuated tube comprises of a
smaller glass tube suspended within
a larger glass tube.The air is then
pumped out of the space between
the small inner tube and the larger
outer tube creating a vacuum
thermal insulation layer.This
vacuum layer is absolutely key since
it reduces heat loss from the solar
collector.

8. Thermo syphon
effect
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• In solar heaters the hot and cold
water will be in same tank
• No pump to make the hot water
flow up the tank
• Hot water will be lighter than the
cold water.
• This lighter hot water will tend to
stay on the upper part
• This is due to its lighter density
• Due to this the hot water will not
get completly in contact with
cold water.
• This process is called syphon
effect.

9. Working
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• Solar radiation falls on the
transparent screens
• The absorber plates will absorb all
the heat energy
• This makes absorber plates to be
heated
• Water will flow inside the tubes
• These tubes are in contact with
absorber plate
• This contact will make the
conduction of heat to water
• Water gets hot enough
• The hot water will flow upwards due
to its light density.
• Thermal insulation is provided to
avoid heat loss
Flat plate collector type

10. Working
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• Solar radiation is absorbed
by the collector
• Coated tube will absorb all
the heat
• It heats up the liquid inside
the tube
• The hot liquid will rise up due
to its low melting point
• Water will flow on the top of
pipe
• Water absorbs the heat of
the liquid inside the tube
• Water gets heated up and
flows into tank
Evacuated tube type

11. Pro’s and
Con’s
• Pro’s
– Renewable
– Non-polluting
– Energy efficient
– No operating costs
– Simple maintenance
– No operating noise
– Highly efficient
– No fuels are required
– Environment friendly
– Current saving
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12. Pro’s and
Con’s
• Con’s
– Limited storage of water
– Requires additional storage tanks and pumps for high
storage capacity
– Dependent on the location’s sunlight intensity
– Might be in effecitive in cloudy areas
– Low heating rate
– Might produce less hot water in rainy or cloudy days.
– Initial cost will be higher
– The orientation and location of the place will effect the
performance
– Requires frequent cleaning in dusty and polluted areas
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13. Applications • Houses
• Textile industries
• Swimming pools
• Hotels
• Restaurants
• Dairies
• Food processing units
• Hospitals
• Nursing homes
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14. Thank you
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