T

Design of Solar Water Heater

GMR Institute of Technology

Presented by:
M. Damodhar Rao(18341A0811)
D. Burn Boss (18341A0808)
Under the Guidance of:
Dr .M. Krishna Prasad
Department of Chemical
engineering

1
 CONTENTS

• Introduction
• Solar Water Heater
GMR Institute of Technology

• Types of Water Heater

• Cost and Maintenance of Solar Water Heater
• Commercial Solar Water Heater as Rural livelihood
• Case Studies & Examples
• Conclusion

2
 INTRODUCTION
• Solar Thermal is a clean,
highly efficient means of
using energy from the sun
to provide hot water for
GMR Institute of Technology

domestic, commercial and

industrial process.
• Example if you place a
container full of liquid in
the garden on a sunny day,
in a short time the contents
of the container become
warm.
• Solar Collectors work in
much the same way, but
are very more efficient. 3
 Classification of Solar Thermal Systems
GMR Institute of Technology

4
GMR Institute of Technology
SOLAR HEATING APPLICATIONS

5
 WHAT IS SOLAR WATER HEATER

• The solar energy incident on the absorber panel coated

with selected coating transfers the heat to the riser pipes
underneath the absorber panel.
GMR Institute of Technology

• The water passing through the risers get heated and is

delivered to the storage tank.
• The re-circulation of the same water through absorber
panel in the collector raises the temperature to about 80
C (Maximum) in a good sunny day.
• The total system with solar collector, storage tank and
pipelines is called solar hot water system.

6
 Salient Features of Solar Water Heating (SWH) System

Solar Hot Water System turns cold water into

hot water with the help of sun’s rays.
• Around 60 deg. – 80 deg. C temperature
can be attained depending on solar
radiation, weather conditions and solar
GMR Institute of Technology

collector system efficiency.

• Hot water for homes, hostels, hotels,
hospitals, restaurants, dairies, industries
etc.
• Can be installed on roof-tops, building
terrace and open ground where there is no
shading, south orientation of collectors and
over-head tank above SWH system.
• SWH system generates hot water on clear
sunny days (maximum), partially clouded
(moderate) but not in rainy or heavy
overcast day.

7
 Salient Features of Solar Water Heating (SWH) System

• Only soft and potable water can

be used.
• Stainless Steel is used for small
tanks whereas Mild Steel tanks
with anticorrosion coating inside
GMR Institute of Technology

are used for large tanks.

• Solar water heaters (SWHs) of
100-300 litres capacity are suited
for domestic application.
• Larger systems can be used in
restaurants, guest houses,
hotels, hospitals, industries etc.

8
 Advantages of SWH System

• Fuel Savings :

 A 100 litres capacity SWH can replace an electric geyser for residential
use and saves 1500 units of electricity annually.
GMR Institute of Technology

• Avoided cost on generation:

 The use of 1000 SWHs of 100 litres capacity each can contribute to a
peak load saving of 1 MW.

• Environmental benefits:

 A SWH of 100 litres capacity can prevent emission of 1.5 tonnes of

carbon-dioxide per year.

9
 • Types of Collector for SWH:
.
 Flat Plate Collector (FPC)
 Evacuated Tubular Collector
(EPC)
GMR Institute of Technology

• Based on system SWH may be:

 Active Systems
• - Open Loop:
 Direct
 Drain Down
- Closed Loop:
 Drain Back
 Antifreeze
 Passive Systems
 Integral Collector Storage
 Thermosyphon

10
 GMR Institute of Technology
Flat Plate
. Collector

11
 Flat Plate Collector.
• It can easily achieve a
temperature 60-80oC above
ambient temperature.
• It uses both beam and diffuse
radiation.
GMR Institute of Technology

• Does not require tracking.

• Requires little maintenance.
• Efficiency: ~ 45% at 80 oC
• Applications: air heating,
water heating, industrial
process heating, passive air
conditioning.

12
GMR Institute of Technology Evacuated tubular Collector

13
 Evacuated tubular Collector
• It can easily achieve a
temperature 80-120oC above
ambient temperature.
• It uses both beam and diffuse
radiation.
GMR Institute of Technology

• Does not require tracking.

• Requires little maintenance.
• Mode: Heat pipe; U tube water;
Integrated Collector/storage
• Efficiency: ~ 55% at 80oC(for
water heating)
• Applications: air heating, water
heating, industrial process
heating, passive air conditioning.

14
 Selection of Collector as per Ambient Temperature
GMR Institute of Technology

15
 Active, Open-loop, Pumped Direct System
GMR Institute of Technology

16
 Active, Open-loop, Drain down System
GMR Institute of Technology

• There is no heat exchanger, which allows efficient heat transfer directly to the
water.
• It does not use anti-freeze or non-potable water.
• The Drain Down System offers freeze protection during power outages or
malfunctioning of the pump or the control systems

17
 Active, Closed-loop, Drain back (indirect System)
GMR Institute of Technology

18
 Active, Closed-loop, Antifreeze (Indirect System)
GMR Institute of Technology

19
 Passive, Integral Collector Storage (ICS) (Direct System)
GMR Institute of Technology

20
 Passive, Thermosyphon (Direct System)
GMR Institute of Technology

Passive, Thermosyphon (Direct System

21
 Commercial Solar Water Heater as Rural Livelihood

• There are many commercial as well as residential uses of

solar water heating.
• In rural area specially in the Himalayan as well as North
Eastern region have a very high demand of commercial
GMR Institute of Technology

solar water system.

• It may be used by the hotels, dhabas, gaushalas, medical
centres, community centres, anganwadis, colleges situated
in the rural areas etc.
• Solar water heater of capacity more than 300 LPD may be
used as commercial purpose.
• In rural areas it also creates livelihoods for the local people
in the field of sales, distribution as well as maintenance &
repairing. 22
 Application of Commercial SWH in Rural Areas

• Large scale hot water usage for bathing & laundry

applications in hotels/dhabas, hospitals, community hall.
• Pre-feed for boilers for steam generation for various
industrial applications.
GMR Institute of Technology

• Milk dairies for applications such as pasteurization,

condensation & cleaning.
• Leather processing industry for drying and tanning.
• Metal finishing industry for degreasing and phosphating.
• Agriculture: Dairy and Livestock industries have a large
demand for hot water used to sterilize the operations on a
daily basis.

23
 Examples
GMR Institute of Technology

Flat plate Solar Water Heater, Pune

24
 Conclusion
• Solar Water Heater can thus provide a sustainable
solutions for meeting the hot water requirements in the
households and commercial establishments in North East
India through savings in electricity and carbon-dioxide
GMR Institute of Technology

emissions.
• Solar water Heaters are environment friendly and will help
in the preservation of the ecosystems that are being eroded
through the increasing use of fossil fuels.
• Hence all of us should resolve to make use of this
opportunity and save our planet for our children.

25
 GMR Institute of Technology

Thank you

26