Project Proposal Feasibility Study
Team17 - NicarAGUA
Seth Koetje - Hannah Van Der Vorst
Jesse Van Der Wees - Dalton Veurink
Engr339/340 Senior Design Project
Calvin College
8 Dec 2014
©2014, Calvin College and Seth Koetje, Jesse van der Wees,
Hannah van der Vorst, and Dalton Veurink.
Executive Summary
Many rural villages in Nicaragua currently do not have access to clean drinking water. A lack of clean
drinking water leads to many easily preventable yet debilitating health concerns. This project aims
to remedy this issue by using an ultraviolet light powered by solar panels to disinfect the water the
people of the community are currently drinking. Villages will be able to buy a subsided disinfection
unit from an organization like World Renew.
Basis of Design
The basic setup of the design is shown in Figure 1. The system will use solar energy to power
an ultraviolet light, which will be used to disinfect contaminated influent.
Figure 1.1: System Setup
The team is not sure what sort of pre-filter will be required for this system. Options include
everything from a simple metal screen for removing large debris to a microfilter if all other
more cost effective options fail. The average monthly solar potential of the area of interest
in Nicaragua is shown in Figure 2, and the monthly variation during the lowest solar
radiation intensity month of December is shown in Figure 3.
Figure 1.2: Average Monthly Solar Radiation
Figure 1.3: December 2001 Daily Average Solar Radiation
From this data, it can be determined that the water disinfection unit system cannot demand
more energy than the average solar radiation over the month of December.
Costs
Table 1.1: Component Cost Breakdown
Component
Solar
Panel Kit
Solar
Regulator
Battery
UV
Light
Housing
Materials
Total
Estimated
Cost [$]
$250
$75
$150
$475
$150
$1100
Implementation Plan
In Nicaraguan villages, the education plan provided in the water disinfection device manual will
describe the effects of poor quality drinking water on individual’s health. As part of the
implementation of the product, the educators desire to bring a microscope into villages in order to
allow the people to see the floating bacteria and debris in their drinking water. The team will then
share information about the effects of drinking water with bacteria and other debris in it.
The manual provided with the product will also include detailed analysis of maintenance and
cleaning of the device. The manual will contain many figures that will explain cleaning and
maintenance of the device to hopefully evade any illiteracy issues.
Table of Contents
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Introduction
1.1.
About the Calvin Engineering Program
1.2.
Team Members Introduction
1.3.
Nicaragua Background
1.4.
Project Statement and Objectives
1.5.
Identification of the Client
1.6.
Design Norms
1.7.
Foreseen Challenges
Design Constraints
Water Demand and Quality
3.1.
Water Demand
3.2.
Rainwater
3.3.
Water Quality
3.3.1.
Nicaraguan Standards
3.3.2.
Other Standards
Alternate Power Supplies
4.1.
Solar Panels
4.1.1.
Direct Normal Irradiance Data
4.1.2.
Diffuse Horizontal Irradiance/Latitude Tilt Irradiance
4.1.3.
Global Horizontal Irradiance Data
4.2.
Wind Turbine
4.3.
Mechanical Crank
4.4.
Gas Generator
4.5.
River Paddle Wheel
4.6.
Conclusion
Current Approaches
5.1.
Design Alternatives
5.1.1.
Clay Pot Filters
5.1.2.
Gravity Carbon Membrane Filters
5.1.3.
Disaster Relief Water Filters
5.2.
Systems in Place
Maintenance
Component Costs
Marketing
Basis of Design
Water Testing
10.1.
Purpose
10.2.
Objectives
10.3.
Key Factors
10.4.
Field Test Plan
10.5.
Equipment and Costs
Acknowledgements
References
Appendix
Table of Figures
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Figure 1.1: System Setup
Figure 1.2: Average Monthly Solar Radiation
Figure 1.3: December 2001 Daily Average Solar Radiation
Figure 1.4: The Team
Figure 3.1: Average Annual Precipitation for Nicaragua
Figure 3.2: Average Monthly Precipitation: Puerto Cabezas
Figure 3.3: Average Number of Days With Rain: Puerto Cabezas3
Figure 4.1: Annual Solar Radiation
Figure 4.2: Monthly Average Solar Radiation
Figure 4.3: December 2001 Daily Average Solar Radiation
Figure 4.4: Annual Mean Wind Power Density in Nicaragua
Figure 5.1: Cross Section of Clay Pot Filter and Basin
Figure 9.1: System Setup
Table of Tables
1.
2.
3.
4.
Table 1.1 : Component Cost Breakdown
Table 3.1: Water Quality Regulations
Table 4.1: Power Source Alternatives Decision Matrix
Table 7.1 : Estimated Costs of Components
1.
Introduction
1.1. About the Calvin Engineering Program
Calvin College places an emphasis on sustainability, international experiences and opportunities,
mission, and service. The Calvin Engineering Department demonstrates these principles by
integrating them into all facets of the curriculum. Students are taught to consider both financial and
environmental factors when making decisions about which components to use when designing a
product. Students experience other cultures through international internships and off-campus
classes. This senior design project aims to incorporate all of these elements.
1.2. Team Members
Our group consists of two Mechanical Engineering and two Civil/Environmental Engineering
students. The Mechanical Engineers are Seth Koetje and Dalton Veurink. The Civil/Environmental
Engineers are Jesse van der Wees and Hannah van der Vorst.
Seth Koetje is from Grand Rapids, Michigan and is passionate about sustainability. This passion has
led Seth to mechanical engineering in order to one day work in the renewable energy industry. Seth
hopes to learn more about renewable energy sources as he works with this team to develop a product
that utilizes this technology. In his spare time, Seth can often be found outside playing ultimate
Frisbee, running, kayaking, or backpacking.
Dalton Veurink is from Salt Lake City, Utah and is studying mechanical engineering with a special
interest in the field of renewable energies and their integration into society. This stems from a belief
that creation care is very important and plays a critical role in the longevity of society. Dalton hopes
to work with and around renewable energies so that they become more economical and further
integrated into the fabric of society. In his free time Dalton can be visiting family in the area, working
on an art project, or reading a good book.
Jesse van der Wees is a Canadian who grew up in Managua, Nicaragua and Haiti. He has always been
intrigued by water. He believes that the sustainable management of this scarce resource is one of the
major social and engineering challenges of this century. The realities of population growth and
climate change call for innovative solutions, and he is very excited to be a part of this process. When
not studying engineering, Jesse enjoys cooking and rock climbing.
Hannah van der Vorst is from Denver, Colorado. She is interested in water conservation and in
providing clean water for the developing world. In her free time, Hannah enjoys outdoor activities
such as mountain climbing, skiing, backpacking, and kayaking. Hannah also likes to use her musical
talents while singing and playing the piano and guitar.
1
Figure 1.4: The Team: Jesse van der Wees, Hannah van der Vorst, Seth Koetje, and Dalton Veurink
1.3. Nicaragua Background
Nicaragua is a country located in Central America between Honduras to the north and Costa Rica to
the south. The primary language spoken is Spanish, but there is a substantial indigenous population
that speaks Miskito. Some Creole-English is also spoken on the Caribbean coast.
The capital of Nicaragua is Managua, its largest city, with a population of about 1.2 million. Much of
Nicaragua, however, is made up of rural villages supported by small-scale agriculture. Many of these
villages can be accessed only by river or poorly maintained dirt roads.
There are two major climate zones in Nicaragua, divided by a central mountain range. The East side
of Nicaragua, where our project will be implemented, has a tropical rainforest climate. Rain falls
every day, and the region routinely experiences tropical storms and hurricanes. Due to widespread
erosion, rivers often have a high silt content. This, coupled with frequent livestock use, compromises
rivers as a source of drinking water.
1.4. Project Statement and Objectives
Currently, many rural villages have no dependable clean water sources. Diseases due to
contaminated water are rampant, but most cases could be prevented with proper water treatment.
Children are the most susceptible demographic to waterborne disease, and studies show that
children who have access to clean water are more successful in school and have fewer developmental
challenges1,2. The objective of our project is to design a system that can collect and disinfect sufficient
water to meet the needs of a small rural village in Nicaragua. To accomplish this, a rain collection
system will capture the runoff water from the roof of a large building in the village such as a school.
Once the rain is captured, the device will implement UV disinfection to sterilize the water. The UV
light will be powered by solar panels. Wind turbines and a mechanical crank will also be evaluated
as potential alternative/backup energy sources. Energy produced will be stored in a battery. The
battery will hold enough power to disinfect water needs for up to one week.
2
1.5.
Identification of the Client
Our client for this project is Mr. Mark van der Wees, who is representing the World Renew in
Nicaragua. World Renew is the "development, disaster response, and justice arm of the Christian
Reformed Church in North America"3. Mr. van der Wees has indicated that there are numerous rural
villages in Nicaragua that lack a reliable source of clean drinking water, and is interested in a
dependable system that can store and treat rainwater in a rural village. Ultimately, our clients are the
residents of the village where our project is implemented.
1.6.
Design Norms
During our design process, we have been careful to keep in mind the eight design norms: cultural
appropriateness, transparency, stewardship, integrity, justice, caring, trust, and humility. Although
all of these design norms are important to this project, the following design norms carry special
significance in this engineering design application:
The people of the village where this disinfection unit will be installed have a culture which is different
from the culture of the designing team. The team must pay special attention to this unfamiliar culture
by learning as much as possible about how it works while they are visiting the village in late January
2015. The culturally appropriate product must be able to be integrated into the culture with a
minimal disruption to the current way of life.
This project will be caring for the customers by educating the people about the needs for clean water
and also providing them with a dependable source to clean water. With a source of clean water, the
village will limit easily preventable health concerns due to the consumption of contaminated water.
This product must obtain the trust of the people in the village by presenting a detailed manual for
showing the community why they need clean water, how this system will provide clean water, and
how to use and care for the system so that it will last. The system will be expected to maintain this
trust by reducing the number of water related health issues in the village.
Finally, the team must exercise humility when designing the disinfection unit. Although the system
may seem intuitive to the design team, the people of the village may not understand how to work the
filter at first. Furthermore, the system is in direct competition with other effective methods of water
treatment. Rather than approach our design as if ours were the only disinfection product available,
the team should strive to refine the system and design it for situations where other systems are
lacking.
1.7.
Foreseen Challenges
Our system will be installed in a remote location in Nicaragua that is accessible only by dug out river
canoes or sometimes by very poorly maintained dirt roads. The remoteness of the villages leads to
problems with routine maintenance because it is hard to provide replacement parts and the technical
knowledge required to repair or replace broken parts.
A concern about the targeted customers is that they may not realize the need for periodic
maintenance and the cleaning of the filters. Neglecting maintenance would shorten the lifespan of the
3
system substantially. Additionally, if the need for clean water is not realized, the people in the village
will resort to drinking untreated water because it is familiar and requires less work. There is a
general lack of knowledge about the dangers of unsanitary water. If an education plan accompanies
the product when it is installed in a village, the device can be used to effectively prevent this sort of
trouble from occurring. Good education plans outline why the water needs to be treated for health
reasons, how to use the device effectively, and how to best perform periodic cleanings.
2.
Design Constraints
The client, Mr. van der Wees, has outlined a number of constraints necessary to make this water
filtration system meet the current needs of the rural villages of Nicaragua. The product must be:
●
Entirely enclosed/self-contained
●
Maintain relatively low costs
●
Easily transportable in a river by a dugout
canoe
●
Easy to clean
●
Provide safe drinking water to the village
●
Storm resistant
●
Have a 10 year operating life span
●
Simple to operate and maintain
These constraints are discussed in more detail below:
The system must be entirely enclosed/self-contained. It would be counter-productive to have
anything interfere with the disinfection process. We would run the risk of infecting clean water with
whatever might accidentally come into contact with a system that is not enclosed. Some examples of
these “infectants” are: curious animals and people, dirt carried by storms, and particulates in the air.
The system must be transportable in a dug-out river canoe, the most common form of transportation
in the targeted villages in Nicaragua. Consequently, the finished product must be no more than 3 feet
by 3 feet by 4 feet, and light enough to be carried by two adults (100 lbs). In addition, the whole
apparatus must be waterproof in the event that it is accidentally dropped into the river during the
transportation process.
The filter must provide clean drinking water to the village. The system will meet or exceed the World
Health Organization (WHO) standards for acceptable drinking water quality. This will be achieved by
selecting rain as the water source and focusing the treatment on biological concerns. A secondary
objective is that the water treatment method does not have a substantial effect on the taste of the
water, such that it remains desirable for consumption.
The customer has indicated that the problem with current water filtration devices available in
Nicaragua is that they require routine maintenance. Also, the current filtration options do not last as
long as desired. For this reason, he has requested that the filter have a 10 year expected operating
lifetime with minimal or no maintenance needs during this time.
The people that the system targets have limited financial means. Therefore, the device must be lowcost so that it is easier for the community to obtain and maintain the system. Materials used cannot
exceed $1200. This way, a village of 20 families could pay $5 per family per month for a year and
cover the material costs of the disinfection unit.
4
The treatment system should be easy to clean. We aim to make this product as simple and userfriendly as possible, and this means minimizing the frequency that the system will need to be cleaned.
We do not want to run the risk of our system failing because it was not cleaned or cleaned improperly.
The system must be able to withstand Nicaraguan storms. Torrential rainstorms are a regular
occurrence and hurricanes are also a possibility in Nicaragua. If our system is to last, it must be able
to withstand these two types storms.
The final constraint is that the system must be simple to operate and maintain. The system must be
intuitive, so that someone with little technical expertise could operate the system with little training.
The design of the system must reflect that user could be of any age or height.
Water Demand and Quality
3.1. Water Demand
Drinking water in many places throughout Nicaragua can contain harmful chemicals and pathogens.
This is especially the case in rural villages where access to water disinfection technologies is nearly
impossible. According to the WHO, a minimum of 7.5 liters per capita per day will meet the
requirements of most people under most conditions6. These villages typically contain about 100
people, so our system will have to be able to treat 750 liters of water per day.
3.
3.2. Rainwater
Rainwater is the primary source of water that we are evaluating. Like any other country near the
equator, Nicaragua experiences a dry season and a rainy season. The rainy season typically lasts
from June to December. During the earlier parts of the rainy season large tropical rainstorms can
be expected at least once a day. The eastern side of Nicaragua experiences more rain than the west.
Annual average precipitation for all of Nicaragua can be found in Figure 3.1.
5
Figure 3.1: Average Annual Precipitation for Nicaragua1
Puerto Cabezas lies on the northeast coast of Nicaragua, as seen in Figure 3.1. It is a location of
interest because it experiences the least rainfall in the region, and has historical weather data is
available. Monthly precipitation for Puerto Cabezas can be seen below in Figures 3.2 and 3.3.
6
Figure 3.2: Average Monthly Rainfall Depth: Puerto Cabezas2
Figure 3.3: Average Number of Days with Rain: Puerto Cabezas3
From these figures, 750 liters of water per day could be supplied provided that the village has a
large tank and sufficient roof area for filling the tank before the dry season. The required tank must
contain 4360 gallons of water. To be safe, the team will assume the village has a 5000 gallon tank
with at least a 200 m2 roof area for water collection (refer to the Appendix for calculations).
7
3.3. Water Quality
3.3.1. Established Standards
Regulations set by the World Health Organization (WHO), European Union (EU), and the United
States Environmental Protection Agency (USEPA) can be seen in Table 3.1 below.
Table 3.1: Water Quality Regulations4
All three regulatory bodies require that there be zero fecal coliform bacteria per 100 mL. Therefore,
the water treatment system will target complete disinfection.
3.3.2. Chlorine
The most common method of water disinfection used in developing countries is chlorine. The
remoteness of the villages where we hope to install our system makes chlorine difficult to obtain.
Our device’s greatest strength is that it uses energy that is available locally in the form of sunlight to
disinfect the water, instead of having to import materials on a regular basis.
4. Analysis of Power Source Alternatives
4.1. Solar Photovoltaic Panels
Solar photovoltaic (PV) panels are the source of power best suited to the water treatment system.
The most significant drawback of solar energy is the variability in its availability. As a result, energy
storage in the form of a battery will have to be incorporated in the design.
4.1.1.
Direct Normal Irradiance Data
The direct normal irradiance (DNI) is the amount of solar radiation that a square dimension sees
within a certain timeframe while normal (perpendicular) to the sun’s rays. This type of data is most
useful when a system is self-tracking to the sun guaranteeing that predominant angle to the sun is at
90 degrees for the most amount of time each day. The minimum annual average DNI of the region
where the system is targeted is 3.498 kWh/m2/day. The average minimum and maximum values
being 2.432 and 4.497 kWh/m2/day, respectively.1 With this lowest value for the area, the design
would be best suited to work under these conditions as it would give the required output even at less
than optimal conditions. This data will give the amount of energy that is available to be captured.
4.1.2.
Diffuse Horizontal Irradiance/Latitude Tilt Irradiance
The Diffuse Horizontal Irradiance (DIF) or Latitude Tilt Irradiance is designated as the amount of
scattered radiation anti-normal to the collection plane. The amount in question comes from all angles
and is a measure of radiation not contingent on direct solar focus. The regional DIF of the same areas
8
is at least 4.828 kWh/m2/day as an average over the whole year. The average minimum and
maximum values being 4.273 and 5.676 kWh/m2/day, respectively.1 This is a good set of data for our
apparatus if the device is designated to be in a more shaded area or one with less optimal visibility
to the clear sky as it is less affected by these factors. Therefore we can then design the apparatus to
be able to work within these less than ideal conditions.
4.1.3.
Global Horizontal Irradiance Data
The Global Horizontal Irradiance (GHI) is the total amount of shortwave radiation seen by the area
at a ground level. This is of most value for Photo-Voltaic (PV) installations and includes both DNI and
DIF values and would be the overall average for the area in question. The regional GHI of the same
areas is at least 4.722 kWh/m2/day as an average over the whole year. The average minimum and
maximum values being 3.907 and 5.832 kWh/m2/day respectively.1 Using these numbers would give
our calculations a reasonably accurate estimate for the conditions the device would see on site as it
includes the DNI and DIF seen there and the total available energy for conversion by the PV system.
There does not seem to be any solar rebates available in Nicaragua, but if the solar panels and water
disinfection unit can be funded through donation, the solar panel option remains a frontrunner
moving forward.
Figure 4.1: Annual Solar Radiation
Figure 4.1 shows the annual solar radiation for 2001 in an area near Rama, Nicaragua. According to
the National Renewable Energy Laboratory’s solar software program called Geospatial Toolkit, this
area is in the lowest solar radiation section of Nicaragua. Although Figure 4.1 shows the wide
variation of radiation experienced each month, it is hard to see how the monthly averages compare
to each other. Figure 4.2 provides this closer look.
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Figure 4.2: Monthly Average Solar Radiation
Figure 4.2 shows that the lowest monthly average for solar radiation is December. Because the water
disinfection device needs to function year round, an in depth look at the lowest monthly average
month (December) will allow the team to see how the average solar radiation varies on a daily basis
during the least sunny period of the year. If the team designs the water disinfection unit for December
conditions, the solar power potential will be more than enough power for the remainder of the year.
Figure 4.3 shows how December 2001 daily averages break down.
Figure 4.3: December 2001 Daily Average Solar Radiation
10
Based on Figure 4.3, it is apparent that in order to produce disinfected water throughout the month,
the team will need to include a battery to store excess power when it is not needed and then use that
excess power later when there is not ample solar power to disinfect the water. The system the team
will design cannot have an average demand which exceeds the average solar radiation during the
month of December.
4.2.
Wind Turbine
Wind generation is a viable candidate for producing energy in many rural areas of Nicaragua.
However, as Figure 4.4 indicates, the wind energy density is very low in the eastern portion of
Nicaragua, where the water treatment system will be implemented.
Figure 4.4: Annual Mean Wind Power Density in Nicaragua
Wind energy power production comes with some inherent risk factors. Tropical storms and
hurricanes are a fact of life in these areas and they pose a threat to a turbine’s durability and
dependability. Since wind turbines typically have to be installed 50 ft. above the highest object in the
area, they are particularly vulnerable to tropical storms or hurricanes. Therefore, because of
inclement weather patterns and minimal winds in Nicaragua, wind turbines do not seem to be an
ideal fit for this apparatus.
4.3.
Mechanical Crank
A hand crank or an adapted bike could serve as a means of power generation. Of these options, the
bike attachment option would have the higher potential for generating power. However, if the bike
would convert the kinetic energy of the wheel into electrical energy for the UV disinfection unit, only
about 30 percent of the pedaling work done would be converted into usable electric work because of
inefficiencies of the motor, voltage regulator, battery, and converter. This low efficiency means that
one would have to pedal over 70 percent harder or longer than if the system were 100% efficient in
order to generate 1 kW of energy. Stationary bike generators are best used when one can convert the
11
kinetic energy into mechanical energy because there are less parts for the inefficiencies to build up
in. If the UV disinfection unit could be powered mechanically, this could be a great option, but since
this is not likely the case, the stationary bike generator seems to not be the best option for this unit.
Another reason this energy source is not ideal is because the disinfection system must focus on
limiting the additional work required to obtain clean drinking water, and a pedal bike would require
quite a bit of additional work.2
4.4.
Gas Generator
Most people in rural areas of Nicaragua have access to a gas generator, but the gas used to run the
generator is very expensive if it is available at all. As a result, a generator is not a suitable alternative.
4.5.
River Paddle Wheel
This idea would tap into the mechanical energy available in the rivers of the area of interest. There
are unfortunately many downsides this alternative. Mainly, there are many mechanical pieces
involved in this form of energy production, which increases the risk of failure.
4.6.
Conclusion
As stated initially, solar panels are the most appropriate source of electrical power for the water
treatment system. Table 4.1 shows how the power sources compare.
Table 4.1: Power Source Alternatives Decision Matrix
Weight
(1 - 5)
Solar
PV
Wind
Turbine
Mechanical
Crank
Gas
Generator
River Paddle
Wheel
Weather Resistant
5
4
1
4
4
2
Initial Cost
4
3
1
4
5
2
Operational Cost
5
5
5
3
1
5
Durability
5
5
2
2
3
2
Limited Amount of
Components
3
4
2
2
4
2
Easy Repair
2
2
2
4
3
3
Energy Production
5
5
1
2
5
4
145
123
59
85
103
85
Total
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5. Current Approaches
5.1. Similar Products
5.1.1. Clay Pot Filters
These filters are already commonly used in Nicaragua. They look like large flowerpots and are
made out of clay that is a combination of clay with ground up dried rice husks or cornhusks. When
these pots are put through the kiln, the husk burns out leaving tiny holes, which allow the water to
slowly flow out of the pot leaving behind microscopic particles and organisms that cannot fit
through the tiny holes. A silver nitrate coating is also applied on the outside of the pot, which kills
bacteria and algae on contact. The final result is that the pot captures 98% of harmful pathogens,
viruses, dirt, and debris in the water. According to Resource Development International of
Cambodia, this system provides a 46% reduction in diarrhea between users and non-users1. Some
advantages and disadvantages are listed below.
Advantages:
● Low cost
● Simple
● Can be made in country they’re used - provide jobs for individuals in the community
Disadvantages:
● Short lifespan
● Routine maintenance required
● Easily breakable
Figure 5.1 Cross Section of Clay Pot Filter and Basin
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5.1.2.
Gravity Carbon Membrane Filters
In these filters, water flows through long tubes lined with carbon membranes. Contaminated water
flows in one side of the tube while clean water is drawn out of the tube from the side and carried to
another set of tubes with finer membranes to be filtered again. This is process is repeated until the
contaminated water has reached the desired standards.
Advantages:
● Low capital cost
● Simple
Disadvantages:
● Membrane replacement can be costly (high variable cost)
● Replacement parts are expensive because they are not produced near the villages like the clay
pots are
● When backwashing system, the filter provides polluted water
5.1.3.
Disaster Relief Water Filters
Disaster relief water filters are in some ways the closest current systems to our proposed system
because they serve large numbers of people by providing large quantities of water.
Advantages:
● Designed to treat daily water needs of large communities
Disadvantages:
● Costly
● Not designed for long term water treatment
5.2. Systems in Place
Rainwater collection systems are currently being used in Nicaragua to gather drinking water in
rural river villages because the river water is full of silt. Once the water is gathered, it is sometimes
filtered using clay pot filters, but some villages still drink the water without any sort of filtration.
This means that any dirt or bird wastes on the roof of the building could eventually end up in the
drinking water. Once the water is gathered from the roof, it is stored in a tank until it is needed.
6. Maintenance
6.1. Ultra Violet Tube Cleaning
Every week the UV ray should be cleaned off. We will design a brush that fits around and slides up
and down the bulb, and will be actuated via a handle from the outside without taking the system
apart.
6.2. Prefilter screen cleaning
When the debris on the screen clogs the intake shoot, the screen can be removed and rinsed off.
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6.3. UV light Replacement
The UV light should be replaced once every 2 years. A small control system will illuminate a green
light when the system is usable, and a red indicator light if the UV bulb is out or too old. The user
will have a maintenance manual for guidance with replacement of the UV light.
6.4. Component Repair
If any part of the system breaks, the disinfection unit should not be used until it can be repaired. For
assistance in the repair process, the maintenance manual provided to the user at the time of
installation will offer a solution to any foreseen problems.
All maintenance needs of the final design will be outlined in a reference book that will be given to
the village when the system is installed. The reference manual will include pictorial instructions to
accommodate children or individuals who are illiterate.
7. Costs
Component cost estimates are given in Table 7.1 below:
Table 7.1: Estimated Costs of Components
Component
Solar PV
Panel Kit
Solar
Regulator
Battery
UV
Light
Housing
Materials
Total
Estimated
Cost [$]
$250
$75
$150
$475
$150
$1100
7.1. Solar Panel Kit
The solar panel kit includes the solar panels and their attachment cables to the solar regulator. The
panels themselves will be made up of multiple polycrystalline cells that make up the photovoltaic
(PV) circuit.
7.2. Solar Regulator
The solar regulator included in this list is what allows the panel array to be combined together into
usable power. This is then input into the battery for charging and later use.
7.3. Battery
The battery itself will be used to store excess energy for later use when treated water is needed.
7.4. UV light
This component is the most expensive and is the primary sanitation method. This means that for a
better level of cleaning or flow rate we must buy a better UV system.
7.5. Housing Materials
The base housing materials will encompass the apparatus for protection and structure. The material
itself will need to be strong yet lightweight so it was decided aluminum will be used for the main
housing components.
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8. Marketing Strategy
8.1. Target Market Demographic Profile
The target villages are comprised of families living on a few US dollars per day. The families are
largely self-sufficient. They typically grow their own food and construct their own homes. They
primarily speak Spanish.
8.2. Customers' Motivation to Buy
Customers’ motivation to add this filtration unit in their village will be driven by educating the people
about the effects of poor quality drinking water on individual’s health. The education team hopes to
bring a microscope into villages in order to allow the people to see the floating bacteria and debris in
their drinking water. The team will then share information about the effects of drinking water with
bacteria and other debris in it.
8.3. Advertising and Promotion
Advertising and promotion of this product will entail having two separate advertising campaigns:
one in countries with prospective donors and one in the rural Nicaraguan villages.
8.3.1. Message
In donating countries, the message will educate potential donors about the water quality of the rural
villages in Eastern Nicaragua. This education will include a detailed description of the preventable
diseases experienced by the children and elderly members of the village, as they are the most
susceptible. Once the situation is realized, the advertisement will propose the disinfection unit as a
solution to the problem and share how the manufacturing process utilizes local Nicaraguan labor to
produce the device. Finally, the message will describe how to donate to the cause.
In Nicaraguan villages, the education team will describe the effects of poor quality drinking water on
individual’s health. The education team hopes to bring a microscope into villages in order to allow
the people to see the floating bacteria and debris in their drinking water. The team will then share
information about the effects of drinking water with bacteria and other debris in it.
8.3.2. Media
The media used to target donors will likely be web pages and social media. The fundraising team will
manage the web pages and create new social media ads for the product.
In Nicaragua, product advertising will be implemented as part of the education plan. The education
team will educate the people in the villages about the need for clean water. Once the people in the
village realize their need, the education team will propose this water treatment device as a potential
solution.
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9. Basis of Design
The basic setup of the design is shown in Figure 9.1. The system will use solar energy to power an
ultraviolet light which will be used to disinfect contaminated influent.
Figure 9.1: System Setup
The team is not sure what sort of pre-filter will be required for this system. Options include
everything from a simple metal screen for removing large debris to a microfilter if all other more cost
effective options fail.
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10. Water Testing (To be done during January 2015)
Important acknowledgement: This chapter is adapted from research done by Team 19.
10.1. Purpose
Perform water testing while in Nicaragua to determine the source water turbidity, which is critical
in UV dosing for effective disinfection. Having turbidity data will enable our team to tune the design
of our system to the needs of the region where it will be deployed.
10.2. Turbidity Analysis
Turbidity, measured in NTU, is an indicator of suspended solids and colloids concentration in a liquid.
Measured by quantifying the amount of light that is able to pass through a water sample, turbidity is
especially important in determining the effectiveness of UV disinfection. However, turbidity also
impacts disinfection efficiency, with higher turbidity levels resulting in lower UV penetration
lessening the overall treatment level of the water.
Digital, reusable turbidity meters can be purchased and used in the field, costing several hundred
dollars. Our team is in the process of researching and proposing one for purchase by the Calvin
Engineering Department, to be brought along on our upcoming trip to Nicaragua.
10.3. Testing Plan
Our team will photograph and record the GPS coordinates of all of the rain collection barrels in the
villages that we visit. We survey community members about their perception of rainwater quality
and get estimates of how sufficient the rainwater storage is during the dry periods of the year. Using
a hand-held turbidity sensor, we will record the turbidity of the water found in the rain barrels. Once
we have returned to Grand Rapids, we will analyze our data and determine a turbidity value to use
in the design of our system.
11. Acknowledgements
Special thanks to environmental engineering professor David Wunder from Calvin College. Professor
Wunder served as the advisor for this project and he raised valuable questions to take into
consideration over the course of the project. His guidance helped deepen the team’s understanding
of the project and made sure the best result would occur at the end of the year.
The team would also like to thank Tom Newhof Sr. for critiquing our design in order to find areas
where the team had weak points. Tom was able to provide meaningful insight for improving the
approach in these areas.
Finally, thanks to Mr. Mark van der Wees of World Renew Nicaragua. He has been very gracious in
providing us with information on Nicaragua and the villages we are focusing on for our project.
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11.
References
1. Chapter 1
1. Halton Region. (n.d.). Retrieved November 09, 2014, from
http://www.halton.ca/cms/One.aspx?pageId=15092
2. Poverty Facts and Stats. (n.d.). Retrieved November 08, 2014, from
http://www.globalissues.org/article/26/poverty-facts-and-stats
3. About Us. (n.d.). Retrieved November 08, 2014, from http://www.worldrenew.net/aboutus
2. Information given by Mr. van der Wees on October 21, 2014
3. Chapter 3
1. World Trade Press. (2014). In Best Country Reports. Retrieved from
http://www.bestcountryreports.com/Precipitation_Map_Nicaragua.php
2. Climate Change Knowledge Portal 2.0. The World Bank Group, 2014. Web. 07
Dec. 2014.
<http://sdwebx.worldbank.org/climateportal/index.cfm?page=country_historic
al_climate&ThisRegion=Latin%20America&ThisCCode=NIC>.
3. Climatological Normals of Puerto Cabezas. Hong Kong Observatory, 2012. Web.
07 Dec. 2014.
<http://www.weather.gov.hk/wxinfo/climat/world/eng/s_america/mx_cam/p
uerto_cabezas_e.htm>.
4. Howard, Guy, and Jamie Bartram. "Domestic Water Quantity, Service Level, and
Health." World Health Organization. World Health Organization, 2003. Web. 8
Nov. 2014.
<http://www.who.int/water_sanitation_health/diseases/WSH03.02.pdf?ua=1>.
4. Chapter 4
1. Glossary of Technical Renewable Energy Terminology. (n.d.). Retrieved
November 08, 2014 from http://www.3tier.com/en/support/glossary
2. Data Retrieved From: http://maps.nrel.gov/SWERA
Data Retrieved From: Geospatial Toolkit Program (2011, May 25). In Low
Tech Magazine. Retrieved from http://www.lowtechmagazine.com/2011/05/bikepowered-electricity-generators.html
5. Chapter 5
1. Ceramic Water Filter. Resource Development International - Cambodia, 2011.
Web. 07 Dec. 2014. <http://www.rdic.org/water-ceramic-filtration.php>.
12.
Appendix
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