Do-Yourself-Solar Technologies

The do-yourself-solar technologies and hands-on solar seminars have been the trademarks we have become known by. On this page we will highlight recent workshop and seminar activities, with photos and special quotes from facilitators and participants. We will also focus at times, on past reports from our work the world over, as well as promoting our up-coming workshops and activities related to our focus. Products and related articles will also be promoted here. 

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65W PV supplies-

and Step by Step procedure for DADS/MESEA ...        

do-yourself-solar, hands-on assembly workshop!

** Summer 2018 update - Maine Solar Energy Assoc. - dadsolar.com   

MESEA  -  65W  PV  Assembly Process  - 

Start the process by acquiring the necessary component parts and supplies:

Solar cells- .5V poly-crystalline PV cells, off-spec., (150mm x 80mm), 36 cells per module, 18V, no load.  (originally from Evergreen Solar, Marlboro, MA, these cells are rated to be Approx: 1.8W @ 3.6 A,  other suppliers available)                            (Volts x Amps = Watts)                                                                               

Liquid silicon – Dow – DC 184 – 8.8lb – Sylgard – 2 part Kit, (Essex-Brownell, [Superior-Essex], Ft. Wayne, IN)   

Tempered glass – 26” x 32”, clear, 3/16” thick, - for 60W module (In some areas double-strength window glass, and other size configurations are used, when tempered glass is not available locally).                                                        

Aluminum frames – For 26” x 32” glass, (or other configuration), Arthaus, Nielsen #22, (or #117), with hardware for corners. (Other possible options, with local restrictions).                                

Backing sheets – White, #20 lb bond paper, (sized larger than glass), for capillary action; and clear vinyl (PVC)  roll stock for finished backing, (sized larger than glass size).                        

Junction box - Handmade, ½” cut caulk tube, to secure wiring to module, with 100% silicone caulk. (UL listed, Multi-Contact, PV – JB/K2, 10A rated and by-pass diode, if desired).                 

Misc. supplies -  Solder, ribbon and tools – Kester brand, lead free, rosin core solder; Weller brand, 40W soldering iron (AC or DC, for local requirement); tabbing (.05mm x 1.5mm wide) and buss (.2mm to .5mm x 8mm wide) tinned-copper ribbon; assorted tools, wire stripper, screwdrivers, scissors, razor knife, clear -100% silicone caulk and gun, 3mil plastic sheet, level table and flexible ½” styrofoam board (base for encapsulation), masking tape and red and blue 16AWG wire.

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We continue with our first step: choosing and soldering PV cells. We check cells from supplier for integrity (Grade B cells may have cosmetic blemishes). After selecting 36 – 40 acceptable cells, for 65W module (some may break during soldering), we set up strings (4 strings of 9 cells or 3 strings of 12), on straight edge for soldering. With tabbed cells (full tabbing ribbon on front, neg. side of cell), the cells are laid on straight edge and tabbing is soldered from front (neg. side), of one cell, to the back (pos. side) of the next cell, (this is done with a maximum of 1/8” space between each cell in the string, we must fit the glass size area), for a series connection, (adding the voltage of each cell). Some cells will need tabbing ribbon soldered on to the front of cells, the ribbons should not touch the next cells ribbon, to avoid a short circuit. After 4 strings of 9 cells (or other configuration), are soldered, each string is checked with digital multi-meter, for minimum no-load output, (4.5V to 5.2V, for 9 cell string), in full sun. (Each string should be about equal, depending on the solar insolation at the moment). An option to use 3 strings of 12 cells  (or 11 in cooler northern climates), making a 36 or 33 cell 65W module, when there is a difficulty acquiring tempered glass, will require a 21" x 41", double thickness window glass. (The 11 or 12 cell strings have 6V to 7.5V output, with various sunlight.)

Our second step: encapsulation, with the Dow Sylgard 184, liquid silicon kit. On our level work table, we lay out a sheet of 3 mil plastic (black garbage bag), on top of styrofoam board for work base. Then the vinyl backing sheet and the #20 lb paper sheet next, (these should be larger than the required glass size). Use a pencil to mark the paper with the glass perimeter, so the PV strings can be added on the paper in the most economical manner, (with the least space between each string and centered on glass size, marked on paper). The strings should be laid on the paper for series connection, (each string end will alternate, pos. and neg.), for adding the volts of each string, to reach our 18V minimum, no-load output. Next, the buss ribbon is cut for the series connections at the string ends, (the center strings, with 4 string configuration, will be the ends for the junction box, on the back). The tabbing ribbon is soldered to the buss ribbon in series, and the pos. and neg. ends of the full 36 cells (buss ribbon ends), are slipped through the paper and vinyl sheets (center of module top), after two small slices are made with a razor knife. The ends are then bent flat and we re-check the string layout for encapsulation. We will add two applications (approx. 7 – 8 fl. oz., or 200ml each), to fully cover the strings and cells as well as the paper. The first Sylgard application is mixed and poured onto the strings, making sure the spaces between the strings are covered. Next, the final application of Sylgard is poured onto the strings and spread gently with plastic mixing cup or fingers. After we have made sure that all the cells are fully covered with Sylgard, we allow the liquid to settle onto the level module for ten minutes. Then, after checking the layout for the last time, we gently place the glass onto the strings, in the exact perimeter drawn earlier on the paper. A piece of cardboard for protection and a weight (30 lb – 40 lb), is applied onto the glass, and we are finished with this step. (The Sylgard will be absorbed through capillary action, to the back of each cell).

Our final step: final wiring and framing, will be accomplished after the Sylgard has “set-up”, which may be two to three days, depending on local environmental conditions. We may have one ready for this step, which has been pre-assembled and allowed to “cure”. The cured module is turned over and the glass edge is used as a guide, to cut back the vinyl and paper with a razor knife. We check the full module output, in the full sun (18V @ 3.6A = 64.8W), usually above the 65W rating. Our caulking tube / junction box is attached to the back of the module (using the 100% silicone caulk to fill the  ½” of cut tube, fully covering and separating the soldered ribbon and wires), after soldering the red (pos) wire and blue (neg) wire (16AWG), for the final connection. These wires may be 12” or 14” for connecting modules to each other in an array. The aluminum framing (Neilsen #22 or other available framing) is installed on the module, using the 100% silicone caulk on the rear and front sides of the module, to seal the module and make a secure frame job. The caulk is allowed to sit for a few hours, while setting up. Solder may be applied at the corners of the frame and a ground screw hole drilled for the earth ground required. After the caulk dries, the excess may be sliced away from the front of the module. Glass cleaner is used for the final cleaning. Another test with multi-meter should be accomplished. We recommend these “handmade” modules be used for off-grid homes and applications. Thank you!

Please refer to Practical Photovoltaics, by Dr. Richard Komp, for detailed explanations of the process allowing the solar illumination (photons), to activate / excite the electrons in the solar PV cells.

Check the websites – www.mainesolar.org and www.dadsolar.com for photos and stories of Int'l. and domestic workshops.

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From pictures on Home page 1, of cell phone charger assembly ...

MESEA Solar Cell Phone Charger …

materials and assembly procedures … Summer 2018

Materials : Solar PV Cells, 4 (to cover breakage) - Si poly-crystalline, 150 x 80 mm (3” x 6”), cut into ¼ size cells (40 x 75 mm), 12 pieces (12 x .5V = 6 V), ¼ cell = .9 A.                                              

Si Caulk (100%), One tube, (GE Silicone1) clear Si caulk.                                                                   

One 9” x 12” picture frame, ($1.00 store) includes frame, glass & backing board.                         

Solder, ribbon, wire and tools, Kester brand, elec. solder – rosin core; Weller brand 40W soldering iron; tabbing ribbon (.05mm x 1.5 mm thick) tinned copper; wire stripper; scissors; razor knife; caulk gun; elec. tape; red & blue insulated 16 AWG wire; diamond cutting wheel (Dremel type); stiff cardboard, cut for scoring the PV cells (40, 75mm); 2 - 1/8” thick plexiglass pcs (3” x 6”) for breaking the scored PV cells;  an electrical  multi-meter for testing the voltage and amperage of each string.

Procedure : Cut the full size (3” x 6”) Si cells into ¼ pieces (40 x 75mm), using the cardboard guide and the diamond cutting wheel, to score the cells. You may need to remove the ribbon already soldered to the cell, and cut one direction at a time. The important aspect is to keep the soldering spot in the same position for each cell. (middle on front [neg] side, with one pad on the back [pos] side). This is to align the cells into equal size ‘strings’ (4 cells x 3 strings = 12 cells), some may break unevenly during scoring or breaking along the score line. (You may also use cells already broken, making sure the soldering spots are aligned correctly). After scoring the cell in one direction with the guide and diamond cutting wheel (5 or 6 times across should be enough, your pressure will determine this), then align the score mark on the edge of and on top of a piece of plexi. Then place the other plexi piece on top of the scored cell and using the edge of the table, allow the top plexi to break the cell along the scored mark. This may take a few times to get correctly, and why we have extra PV cells. Next, score and break the other measure, using the cardboard guide, the diamond cutting wheel and plexi pieces. We do need 12 pieces of cut Si PV cells, each cell is .5V, the size determines the amperage (1/4 cell = .9 A). The finished cell charger is 6V x .9A =5W, rated.         

Next we will solder the cells in a series connection, Neg (front side) to the Pos (back side), which adds the voltage together (a parallel connection, pos to pos, and neg to neg, adds the amperage), using the tabbing ribbon, leaving only 1/16 “ between each cell. Each string will have 4 - ¼ cells, 3 strings x 4 cells = 12 cut cells in all. The ribbon is soldered to the front solder strip with enough extra ribbon to meet the solder pad on the back of the next cut cell in the string. Heat the solder pad or strip with the iron and apply a small bit of solder, spreading it flat. Then hold the ribbon in place and slowly pull the iron along the ribbon and watch the heat transfer to the solder on the strip, melting, and as you remove the iron the ribbon is attached. (You will notice that the ribbon does heat up as you apply the iron, try not to over-heat the strip or pad). Repeat for each cell in each string. We will have 3 strings, each with a ribbon from both ends (one neg [front] and one pos [back]), for our final soldering with all 12 cells in a series connection. We will test the output in full sun (if available) with the multi-meter. Each string should be 2V and .9A, (rated), so we are checking that each string has the same output.

The picture frame is opened from the rear and the backing cardboard removed, marking the space for the 3 strings so the frame will not hit or interfere, and there will be room for a 16AWG wire to fit inside the frame edge. The 3 strings of 4 – ¼ cells are placed onto the inside of the backing board, and a bead of 100% Si caulk is applied across the back of each cut cell, and the full string is then ‘gently’ placed in position and pressed down ‘gently’ onto the backing board. (If there is breakage at this point, we can remove and replace a cell if required). After the 3 strings are placed (each string has pos and neg ends alternating with the next string end, for series connection with solder and ribbon between each string), and caulk applied, the ribbon is cut to connect each string to the next on both ends (so, neg to pos, and pos to neg) and a series connection is accomplished with the solder and iron. A strip of cardboard ¼ “ wide is inserted between each string as well as on all 4 sides of the cells, and caulk added to secure the strips to the backing board. This will allow the glass to touch the strips, so the cells will not be in contact with the glass. Make sure the strips are high enough to accomplish this. Before the final wiring and closure, we will test the entire PV module with the multi-meter, there should be approx. 6V and the .9A for the rated module output.

The framing is checked for a tight fit, with no interference from the glass, cells and frame. The two ribbon ends (one pos and one neg), will have a coordinated 16 AWG wire (red for pos, and blue for neg), soldered to the ribbon and one wire will be placed along the edge of the frame, inside, and come to the other end of the module (so both wires will be on the same end). The two wires will then be put through a hole in the backing board and caulk applied in the hole as well as along the wire inside the frame edge, to hold that in place. The inside perimeter of the frame should be caulked before the backing board is sealed with the pieces designed for closure of the backing board. The PV is thicker than a picture or certificate would be, so there will be a tight fit. The elec. tape (or masking / duct tape) can be applied for extra secure fitting and the multi-meter used again for a final test. As the red and blue wires are both coming out through the backing board, they should have an equal length, approx. 12”. The wires will be matched to a plug from the required phone charger (each phone may have a different plug) and the ph can be charged from a window in the sun or outside facing the sun. We have found that most phones may be charged with this PV module, except an apple I-phone that may require a DC charger plug from apple …

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**Please see the Home page for pictures of the processes above !

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MESEA Small Battery Charger Assembly Instructions : Step-By- Step

Maine Solar Energy Association, Summer, 2018 –

Small 1.5V battery charger (AA, C, D), assembly, step-by-step instructions – the battery charger is designed for use in a south facing window and can be used in winter (low sun), or summer (high sun), the charger can sit on the window sill, with seasonal angle, to fit the sun angle. This will ‘re-charge’ regular ‘Alkaline’ batteries as well as NiCad ‘rechargable’ batteries. *Supplies available from Maine Solar Energy Association (Photos on Home Page)

1 – Cutting the cells for 1.5V battery charger : (2V nominal PV power, to charge on a cloudy day) The more batteries you are trying to charge, the longer it will take to charge. (2 to 5 days, depending on the sun and # of batteries).  Keep in mind that each cell (and cut cell) = .5 V, no matter the size ! The size determines the amperage ! (3” x 6” [150 mm x 80 mm] cell, that we are using = 3.5 amps). When soldering in series (+ to -) back side (grey / pos) to front side (blue / neg), we are ‘adding’ the voltage ! (The other method, parallel soldering, front to front and back to back, [+ to +, - to -], will add the amps. The V will remain the same). Just as connecting PV modules in ‘series’ (pos to neg wire connections), will add the Volts, while wiring in ‘parallel’ will add the amps ! (* Volts x Amps = Watts *)

We start with fresh cells (as reused are harder to cut) … the battery charger needs the full cell cut into six pieces (one sixth = approx 500 ma – [.5 amps], determined by the size of the cut cell). The ‘guide’ for scoring the cell is a thick piece of cardboard with a mark for 75 mm and a ‘factory’ edge to ease the diamond wheel, used for scoring. (We use a diamond wheel, [made for a rotary tool], ‘by hand’), slowly and gently scoring along the factory edge, while holding the cardboard guide firmly and gently against the cell on a solid table, for eight strokes, vertically along the 80 mm front / blue side, between the two solid soldering strips. We cut the cell, by aligning the scored mark, with a ‘flat’ surface and a straight edge (glass or other smooth piece), and then bend the cell using another piece of glass on top, and allowing the cell to be bent with the top piece of glass forcing the cell to bend and break evenly, over the edge of the table. We now have two halves of the cell (80 mm x 75 mm). Next, we do the same using the 26 mm scoring guide, scoring horizontally, across the front (blue side) of the half cell, along the silver ‘fingers’ that help to align the guide for ease of scoring. Again with eight gentle strokes, and then the same action with a ‘flat’ glass or plastic piece, below the scored piece and another piece on top (as above) and a gentle break to allow a smooth 26 mm cut (1/3 of 80 mm, approx.). Then repeat, again, ending with six pieces, about equal in size. Each one is .5 V and about .5 amps (or .6 amps).  (We expect this process to crack and break cells as the technique is learned and therefore, extra cells are provided, in the kit). There will be 40, full 1/6^th,  cut pieces needed for 10 battery chargers, each charger with 4 cut pieces (75 mm x 26 mm), soldered in series to provide the 2 V nominal output to charge the 1.5 V batteries. (The soldering technique is next in these instructions).

2 – Soldering the 4 cut cells into a string : We will solder tabbing ribbon to the 4 cells in a ‘series’ connection (pos / grey side –to- the neg / blue side), adding the voltage for the 2V output needed. The ‘string’ must fit into the space on the white charger case top, without touching the screw heads in the four corners, which attach the metal battery holders to the back. There should be about 1/16“ at most, between each cut cell in the ‘string’ to allow them to fit the space in the case. Since there is only one soldering strip (on front / blue side, neg), and only one soldering pad (on back / grey side, pos), it is important when attaching the ‘string’ to the case (with clear, 100% silicone caulk), that gentle placement and pressure is applied to the cells as they are put into position (not allowing any part of the cut cell to touch the next cell in the string). The ‘tabbing’ (solder ribbons), will be easily cut with a scissor, and just long enough (1” or so), to allow the connection from the strip (front) to the pad (back), without allowing the tabbing to extend past the edge of the cut cell (which could create an electrical ‘short’). At both ends of the ‘string’, a ribbon soldered to each cell (one pos) on the back / grey side and (one neg) on the front / blue side, each ribbon to be soldered to the + or – (back or front) soldering pad or strip. A necessary 2.5” (2 ½ inch) piece of tabbing ribbon, attached to the screw head one side, and fixing the appropriate ‘metal’ battery holder (on back) as the pos or neg for the battery placement. A soldering ‘iron’ with a conical shape ‘tip’ (we use the ‘side’ of the tip), will allow a smooth / flat application of solder and a flat solder ‘joint’ affixing the ribbon to the soldering pad or strip (with a simple and gentle movement, to acquire the ‘flat’ solder joint desired). After each ‘soldering’ action, the tip must be cleaned with a wet sponge and dry cloth. This will require the heat to regain temperature and please ‘be careful’ not to burn your fingers when cleaning the tip. We wind up with 4 cut cells, each with 1/16” between the cells, in a string that has the length to fit inside the screws at the corners of the case (the ‘middle’ screw holes were used with cut cells of a slightly narrower size). This will be affixed gently with a small amount of the clear, 100% silicone caulk and slight pressure to the cell, securing the string to the white case. Then the end ‘ribbons’ are fixed to the screw heads, one on each side, to be the pos and neg side for metal battery holders. (We will describe the metal battery holder position and placement, next)

3 – Metal battery holder and glazing placement and description: The metal battery holders are bent to specifications for the AA, C, and D batteries (the wider D battery holder should be in the ‘deep’ end of the case where the battery will not extend beyond the edge of the case). The bendable fingers on the metal holder, should be on the inside of the metal pieces in the case, and are made to bend and ‘hold’ the batteries in position during charging. Again, the case is designed for winter charging, with 80 degree angle for the lower winter sun, and for summer charging, with 20 degree angle for the high summer sun. A south facing window with access to full sun for at least three hours a day is most opportune. Screws are supplied for attaching the metal battery holders to the charger case as well as connecting the pos and neg ribbons to the metal holders.

The plastic glazing piece, cut to fit into the case snuggly, with the flat side down toward the cells and the textured side up to allow the sun light to disperse with fewer shadows on the cells. This basic solar battery charger was designed and sold by the Maine Solar Energy Association, and Dr. Richard Komp. ** There is a 3-photo close-up of this charger assembly process on the Home Page, and complete description of the process on the Services Page at www.dadsolar.com.

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The three 'step-by-step' assembly processes above, should only be carried out with assistance from a 'qualified' and experienced technician with MESEA affiliation! ... Or with the information available through the MESEA Primer and 'Practical Photovoltaics' (Dr. Rich Komp, PhD, AATEC Publications, Ann Arbor, MI)

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May, 2016 - Guinea, W. Africa - 'RKomp Energie Solaire'... education project. Just a few pictures during the five week span, (en Anglais) !

Yes! The first PV module assembled in Guinea, and encapsulated in a solar oven with EVA sheets! Just a few of the participants, Conakry, Guinea. May 26, 2016! with John Burke.

Handmade 32W PV, and some of the group celebrating for a future in Guinea! May, 2016!

 The group signed the PV module back for Binta, tradition and Dr. Komp!

 Getting ready for installation of the four PV modules assembled by the 'Energie Solaire' group! The workshop building is ready for the solar energy application, May, 2016! Conakry, Guinea. John Burke, MESEA, dadsolar.com.

 Adding PV modules to the homemade 'rack' at the solar workshop, June, 2016, Guinea!

PV 'OFF' switch & 20A charge controller, await the final hookup wiring, Guinea, June 2016.

PV modules ready to install! 32W rated with 1.7A, 18V, at the Equator! Guinea, June 2016.

The 'RKomp Energie Solaire' group with John Burke, MESEA, dadsolar.com, and the almost completed 'solar oven', for the PV encapsulation process! ... May, 2016, Conakry, Guinea.

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Participants at PV assembly workshop, September, 2009, Brooklyn, NY. Selecting cells and soldering strings for 65W PV module.

Drawing for solar thermal installation, showing detail of copper tubing inside insulated box, June - 2008.

Homemade heat exchanger  ready for attachment to tank at Harrington, Maine, solar thermal workshop, July - 2008.

Links and Activities - Downeast Alternative Design Solar, Inc., an educational non-profit Corp. in Maine, in good standing. (Tax deductible, IRS status).

We are pleased to present the On-going, Hands-on SOLAR SEMINAR series!

With our Sister Organizations - Maine Solar Energy Association - www.mainesolar.org ,

Solar Energy Awareness & Demonstration Seminars. Inc., and Skyheat Associates !

Please check the 'contact us' page ** for updated contact, Solar Community Land-trust Development info and Summer 2018 Solar assembly workshop information.

** (Also the form for email communication, thanks)

Drawing for "thermosiphon" hot air collector, to be attached on south wall of dwelling. From Maine Solar Energy Association, Maine Solar Primer, 2nd edition.
* Link for the complete Maine Solar Primer, is on the Home page.

Updated Photo of the solar thermal installation on 'contact us' page.