Portable Solar Lamp
Product Design and Development
Supervisor: Dr. N. Sivakumaran
Team Members
Shreyas Prakash
Prajval Kum...
Abstract
Lot of villages in India are still using kerosene lamps and are widely affected
by frequent power cuts. By using s...
Figure 1: Portable Solar LED Lamp
1 Customer Validation
Before we headed off in making the tangible product, We spent so mu...
with the expensive Solar thermal collector technologies. So we decided to go
with Portable Solar lamp after another round ...
2 Case studies
2.1 Case 1
Rural households: Muthamizh Nagar Talakudi Survey analysis: The group of
families residing here ...
primarily but they wouldnt want to settle for that and prefer mislaneous addi-
tions which when taken in the budget as sho...
(a) (b)
(c)
(d)
Figure 3: Village visits for Customer validation
5
3 Market awareness
A large scale integration option would involve working with Ministry of new
and renewable energy which ...
4 Differentiation
Our team Lumos has built this design of the lamp on the basis of the following
aspects-
• High intensity ...
5 Component specifications of the Solar lamp
Table 1: Components
Components Make Quantity Specifications Comment
On/off switc...
Table 3: Suranaventures PV Module
Nominal Power 10 W
Vmp 18.10 V
Imp 0.55 A
Voc 21.4 V
Isc 0.67 A
Size 305*340*22 mm
6.3 S...
Table 5: Battery specifications
Parameter Minimum rated value Maximum rated value
Operating voltage 12V (14.5 V) Peak
No of...
6.6 LED Specifications
The specifications of the LED are given below for further reference - http:
//www.nichia.co.jp/specif...
6.9 Connections and Wires
Table 10: Connection wires specifications
Parameter Min related value Max related value Comments
...
7.2 Solar panel calculation
Power of the panel = Battery energy/Charge time = 26.4/3 = 8.8W.
So we go for a 12 V, 10 W pan...
Figure 5: B Cu of PCB Design
14
Figure 6: F Cu of PCB Design
15
Figure 7: F Silk S of PCB Design
16
It was very important for the files to be kept Open source as we didn’t want
to use licensed alternatives like EAGLE. Even ...
9 Safety precautions and Guideline
The Solar LED Lantern will do more to improve health and safety than risk it.
The wide ...
of 20

Portable_Solar_Lamp

Published on: Mar 4, 2016
Source: www.slideshare.net


Transcripts - Portable_Solar_Lamp

  • 1. Portable Solar Lamp Product Design and Development Supervisor: Dr. N. Sivakumaran Team Members Shreyas Prakash Prajval Kumar Suraj P K Harish Mari Kiran Sunil Pradeep Padmanabhan November 28, 2015
  • 2. Abstract Lot of villages in India are still using kerosene lamps and are widely affected by frequent power cuts. By using solar lamps, we can provide a convenient and cost-effective way to light streets at night without the need of AC electrical grids. Even with advent of LED and CFL lamps, Solar energy act as an efficient and renewable source of energy helping in illuminating villages, which is the need of the hour.
  • 3. Figure 1: Portable Solar LED Lamp 1 Customer Validation Before we headed off in making the tangible product, We spent so much time on the conceptual phase in implementing a benefiting product to the rural en masse. 1.1 Group Discussion Although we were very much convinced with our customer validation and were ready to proceed with the product development phase, We were skeptical about the feasibility of the product after going through the literature. The reference papers gave us understanding of the technical difficulties and challenges faced 1
  • 4. with the expensive Solar thermal collector technologies. So we decided to go with Portable Solar lamp after another round of Customer validation and test- ing. The main inspiration for proceeding with the development of the Solar lamp was the initiative started by IIT Bombay also known as the Million Souls initia- tive. It was started to mass distribute low cost Solar lamps to almost a hundred thousand school children studying in the rural areas of Bombay. We found this idea pretty novel and a cause which we could give much attention to, as Rural electrification is the need of the hour, especially in India. 1.2 Solar lamp - Report Survey and Analysis The survey involved two sets of prospective consumers, the predominant rural population who are deprived of basic electricity, who would welcome an addi- tional power source based lighting and another set is the elite group who would want to invest on new and better renewable sources. Barely one in every ten households in rural Bihar and two-thirds of houses in the state’s urban areas use electricity to light their houses, Census 2011 figures reveal.Just over half of rural India uses electricity as its main source of lighting, an increase of 12% over 2001. If that seems heartening, the data also shows that 43% of rural house- holds still use kerosene to light their houses, implying that the kerosene subsidy may not be as pointless as some would suggest. In urban India, the spread of electricity is more complete, with 93% of households using electricity as their primary source of light Perhaps the most depressing statistic on this count is that there are still 11 lakh households in India with no source of lighting whatsoever. That is a num- ber slightly larger than the number of households using solar lighting. Data on the other major use of fuels, that is cooking, shows an even less modern picture, with over 85% of rural India still using firewood, crop residue or cow dung as its primary source of fuel for cooking. Even in urban India, the proportion of those using LPG is under two thirds. The proportion of families in urban India using kerosene for cooking has been reduced to almost a third of the 2001 figure over the last decade. But 20% of urban Indians too still use firewood for cooking. For urban and rural areas put together, the proportion of those using kerosene as the primary cooking fuel has come down from 6.5% to 2.9% over the last 10 years. Although the primary aim, is to accommodate the mass production of this product; to cater to the rural electrification needs. On these regards initial survey population involved a village Talakudi, near tollgate Trichy in Lalgudi taluk and a few others who have invested in the existing solar lanterns. 2
  • 5. 2 Case studies 2.1 Case 1 Rural households: Muthamizh Nagar Talakudi Survey analysis: The group of families residing here has already been using a couple of solar lighting prod- ucts but priced at a higher cost than the one we are proposing to design. It was mainly distributed by the local self-help group and hence it was subsidised through loans and they preferred it. It is a LED based solar light which provides 4 modes of brightness and it is provided with a charging panel fixed in their roofs. It also has provision of USB slot to enable mobile charging feature. When the proposition for multiple modes of charging alternative options is enabled in our design they were pretty much interested in investing as this lack of power would be a temporary scenario. Thus they proved a bigger market size for these products besides just reach- ing out to these hamlets they provided a business model through the SHGs and similar NGOs or interest groups. And in comparison to the market players the designed amplification provides better voltage efficiency in our design and thereby increasing the output. On a market size consideration and capital perspective we have a head start due to the cost, besides that having the added subsidies and tenders under the government schemes provide an initial investment opportunity which is risk free and of high returns but this has proved a profitable scenario and that is the reason for many players in the field but not all of them have a technical backing with models accounting on efficiency and the few produced by bigger companies takes an easy compromise on utility factor as opposed to power efficiency as they just concentrate on the charging and power aspects and not the complete design aspects. 2.2 Case 2 Consumers investing on renewable sources: Moving over to the elite consumer group who prefer investing in these lanterns either as to support in case of power failures and to accommodate a cut-off in electrical charging cost of a emergency lamp, If it provides better output there have been an immense interest in al- ternating it with the currently used lighting devices. Also have it in a multi purpose utility category by using both electrical as well as solar charging is a predominantly necessity in the perspective of these prospects. The surveyed testimonial had invested in the lamp costing around 700INR and it has been working for almost 6 years which in their view has been happen- ing only in solar based devices as opposed to normal electrical appliances and hence they are pretty intrested towards getting another one with better output 3
  • 6. primarily but they wouldnt want to settle for that and prefer mislaneous addi- tions which when taken in the budget as shown for our prototype had a warm welcome. Figure 2: Interacting with customers for Demand forecasting Solar lamps 4
  • 7. (a) (b) (c) (d) Figure 3: Village visits for Customer validation 5
  • 8. 3 Market awareness A large scale integration option would involve working with Ministry of new and renewable energy which has a dedicated grid solar power division which currently runs multiple projects with recent increased budget allocations. Its a political promise with a lot of appeal and a massive opportunity for solar and LED providers. India is starved for power. An estimated 300 million plus people arent connected to the grid in India and demand for power is anticipated to double to 2020, according to various estimates. An estimated 27% of the countrys power gets lost through theft and technical failure, while blackouts reduce the countrys GDP by 1.5% annually, according to the World Bank. A blackout in 2012 plunged 700 million into darkness for two days. To top it off, power in India isnt cheap. A substantial portion of the power in rural areas comes from diesel generators. “There are very few options for local sourcing of components such as high- quality lithium batteries and LED components. The ecosystem does not exist. Procuring them from outside India in bulk means that we need to buy and stock them. This blocks our capital that could have been more optimally deployed for marketing and business development operations” Tarun Khurana, Partner and Head of Sales and Marketing, AlphaLoop Solar LLP. “For manufacturing solar lanterns, what we need the most are the SMD type electronic components and assembling equipment, which have a compact design and are cost effective in the production process” G.K. Raju, Managing director, Aditya Solar Energy Pvt Ltd. Challenges faced : No local manufacturing facilities or Indian ecosystem in place for lithium batteries and LED components procuring materials from foreign countries in bulk blocks the manufacturing companies capital that could be used for other important purposes. 6
  • 9. 4 Differentiation Our team Lumos has built this design of the lamp on the basis of the following aspects- • High intensity light should be used so that by tilting the head of the lamp, the whole room can be illuminated. In villages, this might be a crucial need as the study lamp can be alternately used for some other purposes as well. • We have eliminated the gooseneck arrangement found in conventional models, We have made a rigorous analysis on the best user friendly design and come up with this solution. • We will be making the base translucent through 3D Printing. By making the base of the lamp translucent where the electronics of the lamp belongs, the children will be particularly interested in knowing more about the working of the product rather than just use it for study purposes. This is a very crucial design fix as we will be inciting curiosity in the minds of young children, and this will go a long way in making the dream of the Solar urja lamp come true. • The assemblage is quite easy as there are just four parts that have to be grouped together. • We are using Lead Acid batteries in our application for its simple storage and transportation, and due to its environment friendly and recycleable nature. We have a conflict with NIMH Batteries for usage as they have more life cycles, But they are expensive. 7
  • 10. 5 Component specifications of the Solar lamp Table 1: Components Components Make Quantity Specifications Comment On/off switch Elcom 2 Power MOSFET ST microelectronics 1 V(dss) = 60V FFNFO6 R(ds) <0.023ohms I0 = 55A Capacitor TC47/25 AEC 9 47uF, 25V, +/- 20% .01uF and 0.01uF Push switch LED 3 Green LED: charging Red LED: discharging Op Amp LM324 1 Voltage regulator STmicroelectronics 1 IN4007 Diode BJT Mouser Electronics 1 C-B : 40V C-E : 40V E-B : 5V Superbright LED Nichia 5 W, 12 V Zener diode 1 27v Solar Panel Surana Ventures ltd 1 12V/10W Model num: SVL012P Battery AA Portable Power Corp 10 in parallel 12 V 2200 mAh 3 hrs charging gives 6 hrs of discharging time NiMH DC socket Heat sink Local made aluminium heat sink Potentiometer Bourns 100K Ohms Fuse 10A 6 Design and Specifications 6.1 Design files Table 2: Kicad files hyperlinks Design/Sketch Software used Comment Gerber files Kicad Gerber PCB Layout Kicad PCB Layout Schematic Kicad Schematic .gbl file Kicad GBL File .csv file Kicad CSV File Drill file Kicad Drill file 6.2 Circuit performance parameters The solar panel we are using for our application is the 12V/10W panel. For more details, The datasheet is given here - http://www.suranaventures.com/ 10W%2012V.pdf 8
  • 11. Table 3: Suranaventures PV Module Nominal Power 10 W Vmp 18.10 V Imp 0.55 A Voc 21.4 V Isc 0.67 A Size 305*340*22 mm 6.3 Superbright LED Parameters The manual of the LED we are using is given here - http://goo.gl/XKLMmf Table 4: Nichia LED Operating conditions Company Nichia Power rating 4.44 W, 12 v I f 1000 mA Luminous flux 315 lm T (opr) -40 to 125 deg C Directivity 120 deg. 6.4 Battery specifications For the β prototype, We did our testing with the Lead-Acid battery, But for the final product implementation we will be going with the Ni-MH Battery. More details of the Battery we are using is given below - https://goo.gl/ cAzA8F Components Make No.of battery/cells Specifications Comment Sealed rechargeable battery AA Power Corp 10 * AA AA Portable Power Corp 12 V 2600 mAh 9
  • 12. Table 5: Battery specifications Parameter Minimum rated value Maximum rated value Operating voltage 12V (14.5 V) Peak No of charge discharge cycle 600 800 Depth of discharge 10 V Charging rate 0.5 A Standard, Max 1 A. Discharging rate 2 Amp Protection One 65 degree thermostat Terminal Option 1: 6” 18AWG open end wire Option 2: 6” 14AWG Option 3: Standard Male Dean Internal resistance 200 to 300 mOhm Charge voltage 13.6 13.8 Float voltage 14.5 14.9 Gravimetric energy density 60 120 Cycle life 200 300 Self discharge 30% Fast charge time 2h 4h Load current 0.5C or lower 5C Operating temperature -20 degrees 60 degrees 6.5 Switches Components Make Quantity Specifications On/off switch Elcom 2 PBS-1/S Table 6: Switch specifications Parameter Minimum rated value Maximum rated value Comment Mechanical life 5000 10000 cycles Max current rating 26uA Maximum voltage rating 2.7V Temperature range 0 degrees 70 degrees 10
  • 13. 6.6 LED Specifications The specifications of the LED are given below for further reference - http: //www.nichia.co.jp/specification/products/led/NCSW170B-E.pdf Table 7: Nichia LED Company Nichia Identification no NCSWS170BT Quantity 1 Operating Voltage 3.4 - 3.7 V Power Consumption 4.44 W Illumination 315 as per the CIE 1272007 Chart LED Light intensity value 315 lm +- 7 % tolerance LED Reverse current 85 mA LED Angle of view specification Directivity (120 degree) LED Specification for operating life At room temperature (1000 hours) 6.7 Solar panel considerations Table 8: Dimensions of Solar panel Type of Solar Panel Polycrystalline Solar cell size 156 mm Frame type L*W*T = 340*305*22 mm Junction box details 50*40*12 mm Weight 1.2 kg Area 0.1037 mˆ2 Glass specification 330* 295*10 mm 6.8 PV Module performance parameters Table 9: Performance parameters Open circuit voltage 21.4 V Short circuit current 0.67 A Maximum power voltage 18.10 V Maximum power current 0.55 A Temperature coefficient (P max) -0.46%/ deg C Temperature coefficient (I sc) 0.05 %/ deg C 11
  • 14. 6.9 Connections and Wires Table 10: Connection wires specifications Parameter Min related value Max related value Comments Connector style BNC, Co-axial Connector Type Female Jack Number of conductors 4 Conductor type 16AWG, (65*34) BC, 4.02 ohm/Mft Shielding none Insulation type PVC Jacket type PVC Jacket color white Temperature range -65 degrees 165 degrees Electrical impedance 50 ohm Insulation resistance 5000M ohm Power wire dc resistance 0.564 ohm/m Short circuit voltage 50V Jacket thickness 0.025 inches Insulation thickness 0.015 inches Nom. 0.242 Wire coloring Red , Black 7 Documented manual for Lamp manufacture 7.1 Calculations performed Nichia LED Power calculation = 4.44W Operating voltage: 12V Desired operating time: 6hours Capacity = (Led power/ Operating voltage) * Desired operating time = (4.44/12) ∗ 6 = 2.22Ah So we are going to use 12V 2200mAh NIMH Battery. For the selection of the type of the battery: So the total Watt-hour capacity of the battery = 26.4 Watt-hour. 12
  • 15. 7.2 Solar panel calculation Power of the panel = Battery energy/Charge time = 26.4/3 = 8.8W. So we go for a 12 V, 10 W panel. 7.3 Breadboard simulation of the circuit The charge controlling circuit is tested accordingly on the breadboard before proceeding with the PCB Design. The circuit schematic is as follows - Figure 4: Circuit schematic 7.4 Video demonstration of the working of Beta prototype For more details of the working of the prototype, This video could be referred for more insight - https://youtu.be/DFfWRbiX_fM 7.5 Open source Resources Our main aim of this project was to freely distribute the information we gained in assembling the Solar lamp to the public. With this in mind, We setup the Github repository through which all the files are available. The softwares used in this project are: • 3D Modelling : Freecad and 123Design • PCB Design : Kicad 13
  • 16. Figure 5: B Cu of PCB Design 14
  • 17. Figure 6: F Cu of PCB Design 15
  • 18. Figure 7: F Silk S of PCB Design 16
  • 19. It was very important for the files to be kept Open source as we didn’t want to use licensed alternatives like EAGLE. Even though EAGLE is good for PCB Design, It is not appropriate for making commercial products. So we made a conscious choice of using Kicad for our project, although It was time consuming, complicated with a very steep learning curve. The Autorouting techniques avail- able to us through Kicad was really beneficial for our PCB Design as Manual routing was very complicated and were having issues with the routing techniques used. Our github repository is available to the public via this link - https:// github.com/jarusified/lumos We have listed all the Schematic files, Greber files and PCB Files along with the libraries in this repo. Dropbox shared folder of our files: https://goo.gl/tknjev 8 Projected Costs The total cost including the rationing of prices of the PV Module and the battery is coming around 2687/-. This calculation is with the Unit price and the Extended price has not been taken into account. Including the extended price, It would amount to 1500/-. The NiMH Batteries are quite expensive, the trade off being the higher life cycles of around 1500 when compared to the Lead Acid batteries. We therefore did testing with both the NIMH and the Lead Acid batteries. Table 11: Bill Of Materials Component Quantity Cost (Rupees) PCB Fabrication 1 250 Superbright LED 1 35 ON/OFF Switch 1 4 FET 55N06 1 13 2-Pin PUSH Switch 1 2 LED (Indicator) 2 2 Spike wire 1 m 8 2 Heat sink 1 25 Resistors 108 30 LM324 1 9 Potentiometer 2 14 Zener diode 2 4 PNP and NPN diode 2 22 7805 Voltage regulator 1 9 DC Socket and connection wire 1 10 12 V 2200 mAh 1 1400 12 V, 10 W Panel 1 850 17
  • 20. 9 Safety precautions and Guideline The Solar LED Lantern will do more to improve health and safety than risk it. The wide use of kerosene lanterns in India has detrimental effects on both the environment and the people. Small particles released by gas lamps can cause respiratory illness or even lung cancer. The use of clean, brighter LED illumi- nation in place of kerosene will promote safer and healthier living conditions. The NIMH batteries are also very environment friendly as they are recyclable in nature. 10 Scope and Limitations • Brightness regulation of the LED can be done for the next iteration of the product. • Indicator to show the charging mode and discharging mode. • Including USB Jack for mobile charging. • Make it more portable and smaller in size. 11 Bibliography References [1] Design of Solar LED Lighting system. Limin. Li, Li Zhiang, Lin Li, Donghui Wen Kun Wang, 2011. [2] Lacy Billingsly. Solar powered LED Lantern for Developing Countries , 2012. [3] Design of Solar LED Street lamp automatic circuit, Wang Yongqing, Hao Chuncheng, Zhang Suoliang,2009. 18

Related Documents