PROBLEM BASED LEARNING on: Energy Conservation with Rainwater Harvesting

1. ENERGY CONSERVATION
RAINWATER HARVESTING
PREPARED BY :-
Sneh Khajanchi
WITH
(ECRH)
IN THE SUBJECT OF : PROBLEM BASED LEARNING

2. INDEX
ABSTRACT
PRINCIPLE BEHIND OUR TOPIC
ALL POSSIBLE SOLUTIONS
OUR SELECTED SOLUTION STRATEGY
SYSTEM REQUIREMENTS & SETUP
THEORETICAL DESIGN CALCULATION
HOW ECRH SYSTEM WILL WORK ?
PLACES WHERE THIS SYSTEM IS ATTRACTIVE
BENEFITS OF ECRH
CONCLUSION
REFERENCES

3. > In todays polluted and harm environment, we know that the water should be clean and enough to everyone.
When such water is not provided or it is not possible to give people clean water we have to think about
remedies of the water available.
> We know that, Energy can neither be created nor it can be destroyed. It can only be converted from one form
to another.
> Thus, our project will include the modified design of the roof and we will make the roof slanted for the easy
water flow, which will help to utiize the generation of electricity and to store it in a certain form.
> Concluding this it is a problem based learning on Conventional Water storage type of system and
implementing our idea of energy conserving it can be modified,so we named it a 'Energy Conservation on
Rainwater harvesting (ECRH)'.
ABSTRACT

4. 
Energy conservation avoids wasteful use of energy without much investment. It can be termed as a new
source of energy, which when available, can be readily used without any further loss or gestation period.

It is the cheapest source of energy.

Another REASON is;
Electrical power is one of the scarce resources in our country. Generation of electricity is very capital
intensive. 1 MW of power generation costs approximately Rs. 4 crore because of the low plant load factor
and high transmissionlosses prevalent in the country. The installed capacity of power station has to be
therefore, 2.2 times the electrical load.

In fact, it is the easiest solution to bridge the gap between demand and supply.
PRINCIPLE BEHIND OUR TOPIC

5. ALL POSSIBLE SOLUTIONS
We have gone through many of probably possible solitions by which it would
solve our defined problem. Some of them are as under ;
1. Building the Solar Power System
2. Compromising the usage of household appliances.
3. By conserving it with the help of making such commercial setup
4. Using Generator, etc.

6. From the previously given possibility of solutions, we decided to implement such device which do
not impact the comfort of people that compromise it.
So we decided to make such system by which when implementing it , should have been not much
costly and bulky. Our possible solution Conserving the Energy with help of conventional method of
rain water harvesting get done to achieve a system success.
In todays polluted and harm environment, we know that the water should be clean and enough to
everyone. When such water is not provided or it is not possible to give people clean water we have to
think about remedies of the water available.
Knowingly ,Thus, our project will include the modified design of the roof and we will make the roof
slanted for the easy water flow, which will help to utiize the generation of electricity and to store it in
a certain form.
OUR SELECTED SOLUTION STRATEGY

7. 
Water Collecting Surface

Water Collecting Structure

Filter unit (HEPA Filter)

Underground Storage tank

Impulse Turbine (Pelton wheel turbine)

Nozzle

Energy Storage Device
ECRH SYSTEM REQUIREMENTS

8. ECRH SYSTEM SETUP IN BLOCK DIAGRAM
Collected Rain
Water
Turbine Nozzle
FilterStorage Tank
Rain Pipe
Pipe
Water Usage when Need
Energy Storage
DeviceElectricity Usage when in Need
Block Diagram Setup of ECRH
Pipe

9. TYPICAL SETUP OF ECRH

10. THEROETICAL DESIGN CALCULATION
Prior to making any design decisions, we calculated the maximum potential
power harvestable from the system using theoretical values. We considered the
system under two different scenarios: water flowing through a filled downspout and
free falling water.
1ST SCENERIO : In the first scenario, the 21 downspout would have a nozzle at the very end
immediately before the turbine to direct the stream of water on the turbine blades. The small
nozzle area would cause the downspout to backfill and provide a pressure head.
The first scenario involves a nozzle at the end of the downspout. The small nozzle area would
cause the downspout to backfill as rain continues to enter the downspout. If the downspout is
filled, there will be frictional losses in the form of below Equation :

11. THEROETICAL DESIGN CALCULATION
Where:
h1 = Head loss (m) f = Friction Factor (unitless)
L = Lenth of Pipe (m) d = Diameter of Pipe (m)
V = Velocity exiting the pipe g = Gravity ( m^2/s)
> The frictional losses will decrease the maximum velocity that exits the nozzle, and will therefore lower
the power production and the RPM.
> Because the system is small-scale, the goal is to minimize losses as much as possible, therefore a
nozzle at the end of the downspout and backfilling the downspout would not be beneficial.
> Rather, designing the downspout so that the 22 water falls in a single stream down the center of the
downspout to strike the blade will help to enhance the performance of the system.

12. THEROETICAL DESIGN CALCULATION
2ND SCENERIO : In the second scenario, the water would be directed to the center of the downspout
to frictional losses.
The calculations outlined given estimate the power production from a 20 centimeter diameter Pelton
wheel for the case of free-falling water during the heaviest rain.
The Pelton wheel has been chosen for the calculations because the equations are well-developed and
easily accessible.
The first step is to calculate the flow rate of the water off of the roof based on the roof area and rainfall
Intensity.

13. THEROETICAL DESIGN CALCULATION
Theoritical roof area :- 5 Meters in length * 3 Meters in depth = 15 Meters Sq.
Considering in general for past two years from online data , maximum intensity is 272.40 millimeters
per hour and occurs for 0.10 hour (6 minutes) normally.
Then flow rate water entering in pipe ,
Q = A * I
Where: Q = Flow Rate ( m^3/s) A = Adjusted area (m^3) I = Rainfall intensity (m/hr)

14. THEROETICAL DESIGN CALCULATION
As the flow will be of open channel type, therefore assuming all of the potential energy from the
height of the water is converted into kinetic energy, the velocity of the water exiting the pipe is found
using following equation ;-
Where: V = Velocity Exiting the pipe (m/s) g = Gravity (m^2/s) h = Height of Gutter (m)
The height of the roof is estimated to be 3 meters above the ground due to standard ceiling heights.
Thus the velocity of water exiting the downspout is:

15. THEROETICAL DESIGN CALCULATION
The maximum power for a Pelton wheel is modeled by following Equation;
Where,

16. THEROETICAL DESIGN CALCULATION
From the above eqn. We get ,

17. THEROETICAL DESIGN CALCULATION
A 272 millimeter per hour rainfall intensity would last six minutes, from this peak storm the energy
harvested would be calculated in Equation given below,
E = P * T
Where: E = Energy (J) P = Power (W) T = Time that the storm ends (sec)
E = 32.82 360∗
E = 11815 J

18. THEROETICAL DESIGN CALCULATION
CAPABILITY OF GENERATED POWER :
1. A cell phone battery charge requires about 20,000 Joules (assuming cell phone battery holds
5.45 watt hours), the energy can be put into perspective by following equation ;

19. THEROETICAL DESIGN CALCULATION
Over the course of the day the rainfall intensity could be vary, this is just the cell phone charges and
light-hours from a short 6 minute storm. Depending on the rainfall more power may be generated
over the course of an entire day.
2. Lighting one LED for one hour requires 36,000 Joules (assuming 10 W
light bulb), the energy can be put into perspective by following equation ;-

20. HOW ECRH SYSTEM WILL WORK ?

The energy conservation is a technique in which people mostly use and implements day by day.

But with the small upgradation in this system, further it would be a better option with some ease of
power saving and Power requirement.

For that an additional installation with rain water harvesting is Turbine, Energy storage device, and
power supply for providing at the end can easily get upgrade.

When the rain water comes in water collection it will go with pressure head into the Turbine.

By this, the turbine blade will rotate and thus shaft rotates and power will generated. This produced power
will then further go ahead to store it in Energy storage device. By this, whenever in some need of power
this saved energy can be used which is very beneficial.

The water will then comes from turbine to filter with nozzle, and after the better filteration, then water
will then stored in Undergroud storage tank and will then use in need.

21.
1. This acts as a Stand by power unit and will provide the electricity.
2. Groundwater contaminated with Arsenic.
3. Supply from surface and groundwater sources cannot meet the water demand (Urban area).
4. Household do not have capacity to pay for centralized water supply system.
5. Where there is a need of Power in Emergency case.
6. As the power is generated from hydraulic energy by setup of turbine, this is very great future of
Energy conservation.
PLACES WHERE THIS SYSTEM IS ATTRACTIVE

22. 
Relatively cheap materials can be used for construction of containers, collecting surfaces and
Pipes.

With this setup of energy conservation by rain water harvesting, the energy can be easily
obtain and thus the hydraulic energy can be converted into Mechanical energy and then
Electrical energy.

Construction methods are relatively straightforward. Low maintenance costs and
requirements.

The Conserved Energy can easily used in emergency case or in case of some need.

Also, Collected rainwater in storage tank can be consumed without treatment, when a better
Filter Equipment is used.
BENEFITS OF ECRH

23. CONCLUSION

For the current system we are proposing, there are several improvements that could be made if this project
were to be continued. For the current system we are proposing, there are several improvements that could
be made if this project were to be continued.

Further it can be upgraded to such source where the turbine gets run a whole year if some additional
or with small upgradation would be done in which small/mild polluted water from every household
(such as washbasin, bathroom, washing machine, etc) gets collected in downstream of pipe to run the
turbine and so will generate the electricity whole year !

Thus our problem based learning in Energy Conservation with Rainwater Harvesting will prove a
great boon for the habit of good water storage and good life style. We can use the water for over
routine life style and the purpose of cleaning the car and the house.

24. REFERENCES
(1) CarolynDetora, Kayleah Griffen, Nicole Luiz, and Basak Soylu, Worcester Polytechnic Institute (2019).
Energy Harvesting from Rain water, from https://web.wpi.edu/Pubs/E-project/Available/
E-project-032118-144002.pdf
(1) Himanshu Bansal, finhow.com uploads (June, 2013). Eectricity from rainwater harvesting, from
http://www.finhow.com/2013/06/16/electricity-from-rainwater-harvesting/#.XqUi2mgzY2x
(1) Kanth, B. P., Ashwani., & Sharma, S. (2012). House Hold Power Generation Using Rain Water. The
International Journal of Engineering, 1(2), 77–80. Retrieved from www.theijes.com
(1) One of the youtube video shows such a system in action ;-
youtube http://www.youtube.com/watch?v=pp475yj7vvs

25. Thank You