Solar-Powered Water Purification System, 2016
Brenin Ford, Michael Munzer, Connor Kennedy, Brigand Blake
Department of Engineering, Trinity College, Hartford, CT 06106
Project Advisor: Dr. Venkateswaran
System Overview
Background and Motivation
According to the World Health Organization, 650 million people do not have access to clean drinking
water. In addition, 315,000 children under age 5 die each year as a result of poor water quality. This is a
preventable problem. However, industrial water sanitization processes require reliable access to power.
Developing countries do not always have access to power or clean water supply.
Testing Methods and Results
Test 1: Indigo Carmine Die
Problem Definition
To design, fabricate, and test a water purification system with the ability to produce clean drinking
water using only solar energy. The design will require the user to input the unsanitary water. From here,
the system will completely sanitize the water autonomously and then store the potable water in a final
tank where it is ready for consumption.
Our goal was to create a system with the ability to produce 30 liters of clean water per cycle. This
volume is equivalent to a day’s worth of water for ten people. The water that is sanitized and stored by
our system for consumption must meet the EPA standards for potable drinking water..
Our Approach
Indigo Carmine Dye tests under varying power inputs run for five minutes. The
color change from blue to yellow proves the existence of ozone in the system. This
test also proved a correlation between amount of ozone created in our system and
the power input to the reactor.
After considering other sanitation alternatives including water chlorination and boiling, we decided
to creating ozone and reactive oxygen species an air-entrained water flow. This required a water pump
and a high-voltage and high-frequency square wave which is discharged across two electrodes. The
entire system will run on a 24V DC battery bank charged by two 160 Watt Solar panels
The Sanitation Process
First, we created water with a high concentration of bubbles from ambient air by pumping water
through a venturi injector.
Air-entrained water
(foaming water)
1. System Input: Dirty Water
2. Initial Water Tank
3. Initial Sediment Filter
4. Solenoid Valve (1)
5. Secondary Tank: Sanitation
Cycle Tank
6. Level Switch (1)
7. Water Pump
8. High Voltage Reactor
9. Foam Fractionator
10. Fractionator Runoff
11. Solenoid Valve (2)
12. Solenoid Valve (3)
13. Level Switch (2)
14. Final Tank: Clean Water Tank
15. System Output: Clean Water
Venturi Nozzle Schematic
50 Minute
Sanitation Cycle
From here, the air-entrained (foaming) water flows through the reactor and is subject to a square
pulse negative corona discharge between two stainless steel electrodes.
CAD Drawing of Chosen
Electrode Configuration
Real-time Discharge
Across electrodes
A sanitization cycle was run for 50 minutes. By observing dish A, it is clear that
the colonies of bacteria seen in the dish B are successfully destroyed in this time
period. This test was run several times using different bacterial plates with similar
results.
While running one of our bacteria tests with Hartford river water, three
samples were taken using three LabTech drinking water test strips. The water was
cycled through the sanitation system for a total of 50 minutes. Strip samples were
taken after 10, 30, and 50 minutes. The LabTech test strips gave us the following
information measured in parts per million (ppm). The final values met the EPA
standards for safe drinking water. The full EPA table of drinking water
contaminants can be found here: https://www.epa.gov/your-drinking-water/tableregulated-drinking-water-contaminants
1000:1 Voltage Scale
Max Voltage: 240 kV +/- 5%
After testing many different electrode configurations, we decided that a parallel-rod
configuration was the best choice. This configuration resulted in a well distributed discharge inside
the pipe and a large maximum discharge voltage of 240 kV +/- 5%.
After passing through the
high-voltage reactor, the flow
continues through a foam
fractionation system in which
larger contaminants are
fractioned off and removed
from the water. This cycle is run
for enough time to destroy the
contaminants in the water
before it is pumped into the
final tank.
1. Air-entrained Water Flow
2. Fractionation Chamber
3. Fractioned Waste
4. Water Flow, Return to Cycle Tank
5. Solenoid Valve 3
6. Water Flow to Final Tank
CAD Drawing of Foam
Fractionation System
Test 2: Bacteria Plate Count & LabTech
Drinking Water Quality test
Solar-Powered Water Purification System Design
LabTech Drinking Water Test Kit Results