Project Proposal

Faucet-Powered Generator

Figure 1: Faucet Turbine

Figure 2: Turbine BladeFigure 3: Turbine Generator

Justin HawkGustavo Michael IbarguenErhamah Alsuwaidi

ME 340.3, Team 4 (Mean Machines)

Figure 4: Concept Design Assembly

Executive Summary

Our company, which specializes in the creation of water turbines for micro-hydropower systems, has developed a product that is presumed to be our most successful product to date, a faucet powered generator. This product came as the result of a new product opportunity that was discovered by our marketing team. This opportunity called for a consumer product that could attach to a water faucet and produce electrical power to be used for a specific purpose. In order to perfect this product, our team followed a very in depth process including extensive research, establishing the appropriate target audience, assessing customer needs, external searching, benchmarking, and product design. With the help of our marketing team, it was established that our target market as homeowners, farmers, and ranchers. Through surveying and interviewing members of this demographic, important customer needs were gathered to help satisfy features of this product. Our team designed toward the needs that were found to be most prominent and important. First, we discovered that the function the majority of our prospective customers found most interesting and would like this product to carry out was for it to display the amount of water that is used when a faucet is turned on. Other important customer needs were determined such as the ability of the device to perform at a high level while having a low cost, high durability, attractive appearance, and minimal effect on the flow of water out of the faucet. Upon carrying out external searches for current products, similar products were discovered that have gained relative success in the marketplace such as a faucet powered light, radio, a self-powered faucet sensor, and an energy saving device. Our finalized product is a compact, water sealed device that can easily screw onto common sink water faucets without affecting the flow rate of the water out of the faucet. In order to make users more aware of their water consumption, it will display the amount of water being used while the faucet is running. Its inner workings include a water wheel with curved, bucketed blades to maximize performance. Its internal turbine is a combination of the basic, gravity-powered water wheel and the Pelton turbine. Our team has found this design to be the most efficient and feasible for a product of its size, rather than a Francis or Kaplan turbine. Our product will be able to consistently generate a minimum voltage of 1.5V across a 10 Ohm resistor in order to power our display. Estimating a sales volume of 100,000 units per year for 4 years, our company believes that the product is capable of making a profit of approximately $1 million per year if the product is sold for $20 apiece. Please see the following report for details about customer needs, external research, design considerations, a final detailed design, and an in-depth economic analysis.

ContentsIntroduction31.1 Problem Statement31.2 Background Information31.3 Project Planning4Customer Needs and Specifications52.1 Identification of Customer Needs:52.2 Design Specifications5Concept Development63.1 External Search63.2 Problem Decomposition73.3 Concept Generation73.4 Concept Selection84. System Level Design94.1 Overall Description94.2 Preliminary Theoretical Analysis104.3 Preliminary Economic Analysis105. Conclusion106. References117. Appendices12Appendix A: Supplemental Information12Appendix B: Economic Analysis14Appendix C: Theoretical Analysis15Appendix D: Risk Plan Questions17Appendix E: Customer Needs Survey Data18Appendix F: Design Specifications20Appendix G: Problem Decomposition23Appendix H Concept Selection24Appendix H Attestation of Work25

Introduction1.1 Problem Statement

Our company was excited to be given the task of designing and building a water turbine device that could generate electricity from a fluid stream of faucet water. The goal was to design a water turbine product that was capable of producing greater than 0.015 Watts of electrical power without affecting the output flow of water. This electrical energy was to be used to power an accessory of our choosing. The product was to be economically reasonable and able to be easily mass produced. Also, our product was to be especially appealing to our targeted potential clients of homeowners, farmers, and ranchers. Some of the constraints that our company faced in creating this product included: our limited budget for a prototype of $100; the requirement that the outlet of our product terminate in a standard 3/8-18 NPS internal pipe thread; the restriction of not being able to use cannibalized parts in our final design; the requirement that our product generate a minimum of 1.5 volts with a load of 10 Ohms; and the exclusion of water additives to increase electrical output.Our motivation for creating this product was twofold. First, our team realized that this product can have a positive impact on the lives of our clients and the environment. Our product is able to generate electricity during a common household practice that normally does not produce power. By creating a product that can generate electricity to power our accessory without disrupting the use of a faucet or shower, the product will save our clients money that they otherwise would have paid to use the accessory as a standalone product. Also, this energy does not have to be taken from less environmentally friendly energy sources. Second, our company firmly believes that this product has a very high chance of succeeding in the market place. Our marketing team has predicted sales of 100,000 units per year, over the next four years. 1.2 Background Information

In order to develop an efficient water turbine, it is vital to understand the science of how turbines create energy. Regardless of their specific design, all turbines rely on the same physical laws to harness and transfer energy appropriately. For this reason, turbines use similar critical components and processes to function properly. In general, turbines are able to convert the kinetic energy of flowing water into electrical energy. Water flows into the turbine and turns the blades or wheel of the turbine which are fastened to a shaft. This shaft is then attached, through gears or another fashion, to a generator which becomes active when it is rotated by the shaft [2]. The generator uses a stationary, outer magnet and a rotating, inner magnet to create strong magnetic fields and flux. Complex copper wiring is rotated through this magnetic field to generate current. The current is created due to a law of electromagnetism called Faradays Law of Induction [3]. Our company was able to perfect this process on a microsystem level. In doing so, the team has developed the design for a small scale turbine that can fit under a faucet and still generate 0.1836 Watts of electrical power.

1.3 Project Planning

For the faucet-powered hydroelectric turbine project, our team will be following the design method as described in Product Design and Development, 4th ed. [1], and through guidelines provided by Penn States ME 340 course. One of the first steps completed was creating a Gantt chart to evaluate the time needed for each necessary step of the process. The Gantt chart can be found in Appendix A. Following the chart, the team researched basic functions of water turbines and identified customer needs by surveying friends and family that are homeowners. With a basic understanding and knowledge from information gathered, each team member came up with concept drawings and ideas of potential turbine designs. Based on design specifications and customer needs to be met, the best concept that fit the criteria was chosen. This included comparing the provided options for generators and selecting the most efficient generator for each of our concepts. With approval of this proposal, the chosen concept will be constructed into a prototype, tested, refined and tested again, in hopes of producing a final product that meets the goals our company and the expectations of our clients. To complete the design and effectively introduce the product, the company has employed a high level engineer and a marketing professional. As far as resources go, there is unlimited access to a machine shop to build prototypes. Also, the necessary machines and materials at our disposal including not limited to: 3D printers, lathes, milling machines, laser water jets, aluminum, PVC, certain plastics, acrylics, etc. If our product is unsuccessful in meeting the customer needs of our targeted audience for some unforeseeable reason, the company will halt production and begin a revising process. In the meantime, it will sell the failed product at minimal cost. Our risk plan includes performing more surveys and interviews of intended consumers, as well as current product owners. To see a list of possible survey questions directed towards experienced customers, refer to Appendix D. Once the necessary changes have been determined, the team will create a new prototype, and begin its production. Customer Needs and Specifications2.1 Identification of Customer Needs:

Based on the given task, and through prospective client investigation and surveying, our most important customer needs have been established as follows:1. The product should perform efficiently with a high electric power generation. 2. The product should be cost efficient, not exceeding a retail cost of $50.3. The product must be waterproof for durability.4. The inner working components of the turbine should be self-contained. 5. Water flow out of turbine should be steady and oriented straight down out of the product.6. The product must be aesthetically pleasing.7. The product must have a compact, small size.8. The product should be easy to install by screwing onto the faucet.9. The products accessory should be a digital indicator of the amount of water used while the faucet runs.In order to develop these customer needs, our company performed thorough research and solicited the opinions of prospective clients. Our team has created a comprehensive survey outlining the important features and functions of our water turbine ideas. Next, we asked several homeowners, a select few of whom either currently or previously lived on farms, to compare and rate the important characteristics that would possibly be incorporated into the design of our product. A full sample of these house owners were chosen, specifically those with farm or ranch living experience, because it was known that this was the demographic benefit the most from this product. The results of these surveys can be found in Appendix E. The team took it a step further with a few of our customers and conducted interviews with them. In these interviews, we explored our survey questions much deeper, asking them to explain the logic behind their choices and received feedback on some of the ideas were generated.The surveying and interviewing stages allowed us to determine that prospective clients cared first and foremost about the performance and cost of the product, as well as, the function of its accessory. These were major talking points during the interviews that were conducted. Secondly, they wanted to ensure that the product would operate efficiently and that it was water resistant for durability. Next in the order of relative importance was their concern that the water output may not be steady and oriented in the proper direction or that water may be leaking from the product -faucet connection. Lastly, they expressed their sentiments on the size, appearance, and loudness of the product during operation.2.2 Design SpecificationsBased on our gathered customer needs, design specifications were set for our product. These specifications can be viewed in Appendix F, Table F3 which details the metric, corresponding needs, the units for each metric, the ideal value for each metric, and the relative importance of each metric on a scale from 1-10. Furthermore, the relationship between these metrics and the customer needs is mapped out using the Quality Function Deployment method. These results can be seen in Appendix F, Table F4. The relative importance of each customer need was calculated using the Analytic Hierarchy Process method. The resulting weight percentages of importance for each customer need can be viewed in Table 1 below. Detailed tables that show AHP method being carried out can be found in first two tables of Appendix F.Customer NeedWeight Percentage (%)

1. Performance26

2. Cost19.5

3. Durability16

4. Self-contained10.5

5. Downward outflow7

6. Appearance7

7. Size10

8. Ease of Installment4

Table 1: Weighted Customer Needs

The data collected and outlined in the design specification and weighted customer needs tables was used when selecting design concepts. The specifications that correspond most frequently to the customer needs with the highest calculated importance were given priority over the others. Our design concepts were created with the goals of satisfying the prioritized needs first, even if they constrained the design from fulfilling the rest of the needs. In doing so, our company has ensured that our customers most important needs, such as high performance, reasonable cost, and durability will be met.Concept Development

3.1 External Search Our team began searching for the most effective water turbine available to ensure that our product will operate with maximum performance and efficiency. First, research was conducted to determine the different types of water turbines and their respective advantages and disadvantages. The two categories of water turbines, reaction and impulse turbines, were analyzed. The impulse turbine uses the transfer of momentum from the flowing water to turn the wheel and shaft, thus powering the generator. Examples of impulse turbines include the Pelton wheel and the basic water wheel. These types of turbines work best under high head and low water flow applications. Reaction turbines are different from the impulse turbines, mainly due to the orientation of their blades. Their blades are oriented perpendicular to the flow of water and are most efficient when water contacts all of the blades simultaneously. Examples of reaction turbines include Kaplan and Francis turbines. These kinds of turbines are more suitable for high flow conditions. All of the aforementioned turbines were considered during concept generation and selection which is detailed in sections 3.3 and 3.4 of this proposal.

Furthermore, our research revealed a lot of previous products and ideas for water faucet-powered generators. One of the cheapest products found was the Barite Faucet that costs around $35.00 and produces light. A more expensive product is the T & S EC-HYDROGEN which generates and stores electrical energy. This product costs around $103.00. Other products were found to have accessories such as a radio, a temperature display, and an ozone water purifier. 3.2 Problem DecompositionIn order to better understand the problem to be solved, it has been functionally decomposed used a black box diagram. This Diagram is labeled Figures G1 and G2 and can be found in Appendix G. 3.3 Concept Generation

Our team developed and analyzed several different concept designs before reaching the final design for our project. After extensive brainstorming of many different designs, we were able to narrow down our concepts until there were four designs to consider seriously.

Concept Design #1: This design is similar to that of a basic water wheel. It has a large central wheel aligned vertically with the direction of the water inflow and outflow. It has curved, bucketed blades to combine the force of impulse and gravitational force due to collected water. The turbine has a rounded housing to fit the shape of the wheel that it contains. This shape will ensure that any errant water flows smoothly to the outlet so that the water outflow has the same characteristics of the water inflow. Lastly, the shaft is connected to the generator through a series of gears. Figure 5: Concept #1

Concept Design #2: This concept idea also has a vertical wheel but has blades that resemble those of a Pelton turbine, although they are not as abundant. An important aspect of this design is that it uses a nozzle to increase the velocity of the water as it enters the system and allows for greater control of this water flow. With this type of control, it can be ensured that the water hits the sweet spot of the blade in order to maximize the force and torque translated to the shaft of the water turbine.

Figure 6: Concept #2

Concept Design #3:The shape of turbine wheel in this design concept is very similar to that of the first design except the blades are not buckets. Rather, these blades are flat, angled paddles. In this design, the generator is located directly on the side of the housing and it is connected to the wheel by the shaft without using any gears. Another important aspect of this design is that the water inlet and the water outlet are located on the same side of the housing so that water flows directly to the outlet.

Figure 7: Concept #3

Concept Design #4:This concept design, which utilizes a Kaplan turbine, is very different from the other three designs. As can be seen in the picture, its blades are oriented in a direction perpendicular to the inflow of water. Also, the generator is located on top of the housing. It is connected to the turbine by the shaft and using gears so that it does not interfere with the position of the faucet.Figure 8: Concept#4

3.4 Concept Selection

Concepts

Concept #1Concept#2Concept#3Concept#4

Sum +s5551

Sum 0s3221

Sum s0116

Net Score554-5

Rank1234

Continue?CombineCombineCombineNo

Table 2: Concept-Screening Matrix Results

This was the teams concept-screening matrix. By going through the selection criteria, each feature was given a better than (+), same as (0), or worse than (-), to rate that feature. When looking at the table, it can be determined that concepts 1, 2, and 3 scored very well (net score 4 or better). Concept 4 was evaluated with the same criteria and failed to impress with its net score of -5. With the aid of the concept screening matrix, the team was able to make the decision to combine the first three concepts because of their close scores while putting concept 4 on hold. The full concept-screen matrix is labeled Table H1 in Appendix H.

Concepts

Concept #1Concept #2Concept #3Concept #4

Total Score421.5389.5405.5279

Rank1324

Continue?CombineCombineCombineNo

Table 3: Concept Scoring Matrix Results

When evaluating the concepts generated, a concept-scoring matrix was used to compare them. From the AHP method, the weight of each selection criteria was multiplied by its corresponding rating for each concept to get a weighted score. All of the weighted scores were then added together to see the total score in the table. Concept 1 ranked highest, closely followed by concepts 2 and 3. However, much to no surprise concept 4 trailed far behind other concepts. Because of the close scores, it was determined that the first three concepts be combined. Concept 4 would not be further pursued because of its low score relative to the other concepts. The full concept scoring matrix is labeled Table H2 in Appendix H.

4. System Level Design4.1 Overall Description

Figure 9: Exploded View of Turbine

The final design our team has chosen can be seen above. Standing 2.7 tall, the rounded housing was chosen to help water exit the system in an orderly fashion. The blade contained within the housing has eight bucket shaped blades that provide maximum rotation of the wheel due to impulse and gravitational forces. This feature is attached to a round shaft that connects directly to our chosen generator. To keep the generator from experiencing water damage while containing the turbine and providing transparency, two identical pieces of Plexiglass are used for the sides of the housing. Each piece contains a hole for the shaft to go through so that the turbine is balanced at all times. The generator is then covered by its own case, to help ensure further that is not damaged and to add to aesthetic apeall. As part of the housing, the water inlet will also include a nozzle that takes the 3/8 hole down to a 1/4 diameter hole to increase the velocity and control of the water flow.4.2 Preliminary Theoretical Analysis

In performing theoretical analysis on the performance of our product, it has been determined that this device will be able to generate a voltage of 3.6 Volts and supply a power of 0.1836 Watts due to a torque of 56.1 g-cm being delivered to the generator. These values are based on our calculated value of 1122.997 RPM, the speed at which the shaft of our water turbine will rotate. This leads to a 40% efficiency of our generator (#238473). For detailed calculations, please refer to appendix C.

4.3 Preliminary Economic Analysis

Our team carried out an economic analysis in order to predict the most suitable retail price for our product. Based on our survey and interview results, the retail price was set to $24.99, which falls in the range of prices that the majority of surveyed customers expressed they would expect to pay for this product. Also, it is estimated that our companys sales will be around 100,000 units a year, which will give us revenue of $2.499 million a year.

The cost of production includes several components. The company plans on producing 110,000 units per year to ensure that there will be extra devices to sell if demand is greater than expected. The cost of the materials is $9.50 per device plus the cost of approximately $3.0 per device for production and assembly. This cost is based on the assumption that we can produce and assemble 20 of these devices per hour in our facilities, given that the labor cost for manufacturing and assembly is $60/hr. Also, the company hired two engineers and two marketing specialists to assist us during this project. The salary for each of these professionals, including fringe benefits, pension, medical costs, and overhead is $120,000 per year. Therefore, $480,000 will be paid out yearly as the total cost of salaries. Adding all costs together, provides a total cost of $1.855 million per year. Subtracting the yearly total cost from the yearly total revenue gives us a profit of $644.9 thousand per year. Since it is projected that our sales will remain constant over the next four years, it can be expected to obtain a profit of more than $2.5 million during this period.

5. Conclusion

Our team has come a long way since being assigned this project. Beginning with background research and customer surveillance, our company established project goals we have now been able to achieve. Concepts were generated based off of the data collected and compared using decision and selection matrices. A final design was chosen and created in SolidWorks by combining the best attributes of a few of our concept designs. A Gantt chart helped keep project tasks on time and will guide the team until the project is completed. Our team, Mean Machines, have put in an extensive amount of time into research and development of a faucet powered water turbine. Our final design is unique in the way that it has a rounded housing and a wheel with bucketed blades. The blade design is unlike any on the market and will be most effective in providing extra torque to produce power. The sleek design of the housing assures that water exits the system smoothly and efficiently. This product will highly appeal to consumers because of its compact design, low cost, and efficient features. Its accessory of a digital display to show the amount of water used while the faucet runs will benefit the customer as it will make them aware of their water usage, inclining them to cut back, and thus save water and money. With conserving resources, especially water, at the forefront of technology development today, we believe our product can be extremely useful. We are confident that our product will be successful in the extensive market of homeowners, ranchers, and farmers who desire to save water and money. 6. References

[1] Ulrich, Karl T., and Steven D. Eppinger. Product Design and Development. 4th ed. Boston: McGraw-Hill/Irwin, 2008. Print.

[2] "Water Turbines and Their Uses."Water Turbines and Their Uses. N.p., n.d. Web. 16 Feb. 2014. .

[3] "How a Generator Works."Turbine Generator Atom. N.p., n.d. Web. 16 Feb. 2014. .

[4] "Jameco Electronics." - Electronic Components Distributor. N.p., n.d. Web. 03 Apr. 2014.

[5] "Water Usage" EPA. Environmental Protection Agency, n.d. Web. 03 Apr. 2014.

Picture Sources

Figure 1:http://www.facilitiesnet.com/graphics/products/-ms11/ms1011Chicago.jpgFigure 2:http://www.turbogen-engineering.com/immagini/blades.pngFigure 3:http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?search_type=jamecoall&catalogId=10001&freeText=2120461&langId=-1&productId=2120461&storeId=10001&ddkey=http:StoreCatalogDrillDownView

7. AppendicesAppendix A: Supplemental Information

Gantt ChartFigure A1: Gantt Chart

Team Roles Gustavo Michael Ibarguena) Team leaderb) Communication facilitator c) Primary presenter and work organizer

Justin Hawka) Lead machinist b) Primary SolidWorks engineerc) Meeting Recorder

Erhamah Alsuwaidi a) Main concept developerb) Meeting recorderc) Research specialist

Qualifications

We are a strategically organized team of mechanical engineers who specialize in the design and development of efficient microsystems and small scale machinery. Each of us have unique backgrounds, talents, and skills which allows for a combination of perspectives to maximize variety and efficient collaboration. Due to the experience gained in the engineering field and our background education, our team is confident that it will perform exceptionally in project. Also, during prior projects, the team has demonstrated the ability to succeed in the product creation process which includes concept development, concept selection, sketching, SolidWorks modeling, and prototype machining.

Appendix B: Economic Analysis (N/A at this time)

Appendix C: Theoretical Analysis

Variables:m = mass mdot = mass flow rateVdot = volume flow rate (constant) = density V = velocity of water flow leaving faucetV = velocity of water flow entering systemV = velocity of water leaving system = angular velocityR = radius of water wheel Position 1 = position that water exits the faucetPosition 2 = position that water enters the systemPosition 3 = position that water exits system

Assumptions/Known:Momentum of the water that contacts each blade is conserved and transferred to the blade. The linear velocity of each subsequent blade will increase continuously until the linear velocity of the blade is steady at a value approximately equal to the velocity of the water inflow. This phenomena is verified by performing infinite iterations using the equation for conservation of momentum: m1u1 + m2u2 = m2v1 + m2+v2 where u is the initial velocity, v is the final velocity, m is the mass, 1 stands for the water inflow, and 2 stands for a blade on the wheel. w = 998 kg/m3Vdot = 1.5 gallons/min. = = 0.00009464 m3/s [5] r1 = .1875 in. = .0047625 m r2 = 0.125 in. = .003175 mR = 1 in. = .0254 mIn order to ensure that mdot is equal at positions 1 and 3, the area of the outlet must equal to the area of the inlet. * All unit calculations were carried using Googles unit converter

Calculations:V1 = Vdot,1/ A1 = (.00009464 m3/s) / [*(.0047625 m)2] = 1.328 m/sConservation of mass: mdot,1 = mdot,2 mdot = V1A1V1A1 = V2A2 V2 = (V1A1)/A2 = [(1.328 m/s)* *(.0047625 m)2]/[*(.003175 m)2] = 2.988 m/sV = wheelR wheel = V/R = (2.988 m/s) / (.0254 m) = 117.6 rad/swheel = 117.6 rad/s = 1122.997 RPMwheel = shaft = 1122.997 RPMAfter referring to the generator data collected in class, the ideal generator for this angular speed of 1122.997 RPM was chosen to be generator number 238473. At a value of 1122.997 RPM, the efficiency of this generator is approximately 40%. Please see Figure C1 below.

Figure C1: Generator Data

The following are calculations of the values for this generators performance at an efficiency of 40%, based on the values provided by Jamecos website for this generator operating at maximum efficiency. This generator has a maximum efficiency of 75%.

Nominal Voltage = Vmax * (0.40/.75) = 12 V *(0.4*.75) = 3.6 VCurrent = Imax * (0.40*.75) = 0.17 A * (0.4*.75) = 0.051 ATorque = Tmax * (0.40*.75) = 187 g-cm * (0.4*.75) = 56.1 g-cmPower = VI = 3.6 V * 0.051 A = 0.1836 W

Appendix D: Risk Plan Questions1How often do you use this product/How many do you have in your home?

2Overall, are you satisfied with the product?

3What do you consider to be the best feature of the product?

4What feature(s) of this product, bug you or do not work properly?

5What would you change about this product?

6Did this product satisfy your needs? If not, why?

7Would you recommend this product to others, why or why not?

8Do you feel that the product was reasonably priced?

Table D1: Risk Plan Questions

Appendix E: Customer Needs Survey DataCustomer Needs Survey What would you prefer that the electricity generated by this turbine be used for?1.) Radio 2.) Clock3.) Light4.) Display of water used

Which of these categories do you feel is the most important?1.) Appearance2.) Size3.) Functionality/Efficiency4.) Cost

What would you expect to pay for a product that generates electricity from water flowing out of the faucet like this product does?(in $)1.) 0-102.) 10-303.) 30-504.) 50-75

Rate these features on a scale from 1-10 on importance.1.) Water Resistant2.) No Leakage out of faucet3.) Loudness/Noise4.) Steady supply of power

How concerned are you about the orientation of the outflow of water, with straight down being the ideal direction?1.) Very concerned 2.) Mildly concerned3.) Not concerned at all

Customer Needs Survey Results (Totals are tallied in parentheses)What would you prefer that the electricity generated by this turbine be used for?1.) Radio (7) 2.) Clock (4) 3.) Light (9) 4.) Display of water used (10)

Which of these categories do you feels is the most important?1.) Appearance (4) 2.) Size (4) 3.) Functionality/Efficiency (9) 4.) Cost (13)

What would you expect to pay for a product that generates electricity from water flowing out of the faucet?1.) 0-10 (4)2.) 10-30 (15)3.) 30-50 (9)4.) 50-75 (2)

Rate these features on a scale from 1-10 on importance.1.) Water Resistant (~9 average)2.) No Leakage out of faucet (~7 average)3.) Loudness/Noise (~4 average)4.) Steady supply of power (~6 average)

How concerned are about the orientation of the outflow of water with straight down being the ideal direction?1.) Very concerned (22) 2.) Mildly concerned (8) 3.) Not concerned at all (0)

Appendix F: Design Specifications

Customer Need12345678

1. Performance1:13:22:13:14:14:13:15:1

2. Cost 2:31:13:22:13:13:15:24:1

3. Durability1:22:31:13:25:23:13:24:1

4. Self-contained1:31:22:31:13:23:21:13:1

5. Downward outflow1:41:32:52:31:11:12:32:1

6. Appearance1:41:31:32:31:11:12:32:1

7. Size1:32:52:31:13:23:21:15:2

8. Ease of installment1:51:41:41:31:21:22:51:1

Table F1: AHP Ranking of Needs

Customer Need12345678Net ScoreWeight Percentage

1. Performance11.523443523.526

2. Cost.6711.52332.5417.6719.5

3. Durability.5.6711.52.531.5414.6716

4. Self-contained.33.5.6711.51.5139.510.5

5. Downward outflow.25.33.4.6711.6726.6327

6. Appearance.25.33.33.6711.6726.257

7. Size.33.4.6711.51.512.58.910

8. Ease of Installment.4.25.25.33.5.5.413.434

Table F2: Weighting of Needs

Metric #Need #MetricImportanceUnitsIdeal Value

11Electrical power generated10Watts>.015

21Voltage generated10Volts>1.5

31Efficiency9%80

43Product lifetime8Years5

54Inner workings are self-contained6BinaryYes

62Retail price8$