DIY Solar Photovoltaic Workshops: Learn and Teach the Skills to Build Your Own Handbook of Materials and Instructions
By Daniel Quiggin
[email protected] 07793107684
www.diy-solar-workshop.org
Build Solar Panels for 1/2 Price of Retail Cost Share the Skills, Make your Community Resilient, Reduce Consumption of Energy, Challenge Centralised Energy Reliance and Fight for Social Energy Justice
This is the first handbook for this workshop. Comments, suggestions and feedback are all welcome; either via the website or by email. Due to time constraints and an evolutionary approach to this project some concepts, issues etc are missing. Please feel free to suggest blindingly obvious additions. Supplementary material on circuits and how the solar cells work is available. If you have taken part in a full 1 day workshop then elements of the workshop won’t be covered in this guide. The limitations of the handbook have been drawn in order to make it possible to write the handbook without a huge book publication being needed. This means the handbook doesn’t cover concepts like the orientation of the panel, connecting panels to 12 volt systems, charge controllers, Maximum Power Point Trackers, connecting the panels to batteries etc. For this detail please contact me to attend a workshop. The project has been designed to make affordable solar panels for low income households –as such the panels don’t meet factory quality and as a guide will likely last 10 years rather than the 25 guaranteed by factory quality panels. If you follow other DIY guides for making solar panels you will find many different methods, the method used here aims to achieve 50p per watt. Other DIY methods may achieve a longer lasting panel but at increased cost. Also please be aware that all DIY panels do not qualify for the Feed-in-Tariff. 1. Introduction This handbook is for anyone interested in building their own solar panel. Renewable technologies are more than just about reducing CO2 emissions, energy has political, social and economic implications. A brief overview of a few of these
important issues is given, along with a step-by-step guide of how to construct a 50Watt solar panel, how to source the materials, costings and what to do with the panel. It is possible using this method to construct any size panel. One day workshops are available, only the basics of panel construction are contained within this handbook. The next section explains the workshop concept and how to get involved.
you would be set back around £4,500. To compare like for like it’s only fair to use the materials cost. So that’s £1.20 per watt of power. If you follow the guidelines set out here and make sure you “tat” all you can (including the batteries) I calculate you will spend 55 pence per watt. Less than half of the price, which I hope makes this technology much more accessible to the less financially affluent of us.
A not-for-profit Workshop, Skill Share Model
For photos of some blue peter style, “this is what I made earlier”, panels please see the website.
Funding for this project has been kindly provided by Unlimited. Unlimited mission is “to reach out and unleash the energies of people who can transform the world in which they live”. This project is not looking to make money, rather to share skills, inspire each other and develop collective community resilience. As such the following workshop model has been developed; individuals or groups attending level one workshops are given materials to run a level two workshop where they charge participants cost price to make a solar panel. This money is then passed back to the project to buy new materials and the process starts again. This model is designed to spread the workshop as quickly as possible and keep the costs to a minimum such that low income households can afford to attend workshops. Please get in contact if you wish to participate. Donations are welcome as equipment damage and other boring externalities will eat away at the original pot of money. 2. A Quick Overview The basic idea is that we take “broken” solar cells and like any good recycling scheme reuse these cells to make new solar panels. The project is designed to construct these panels with the least cost such that low income households can afford to access renewable power. A typical 1kW solar system will cost £1,200 for just the materials, for the installation of a 1kW system
The entire point of making DIY solar panels is to reduce our energy consumption. By learning how solar panels work and constructing them ourselves, we are more likely to marry up supply of power to demand for power and through this awareness start to reduce our consumption of power. The Feed-In-Tariff is driving the current rise in ownership of solar panels, which is generally on thought of positively. The Feed-In-Tariff pays solar panel owners roughly four times the cost of electricity for every kilowatt of power the panels produce. The way this is paid for is by all energy consumers being charged more money per kilowatt of power they consumer. The energy suppliers then pass this extra money onto solar panel owners. This in essences means the poor are paying the rich for their solar power. This is an inverse Robin Hood tax and is increasing the social inequality of the energy system.
3. Where do the Solar Cells Come From Solar cells (monocrystalline silicon) are manufactured in china and then shipped to Europe where they are assembled into
panels. The “broken” cells are those that end up slightly chipped or damaged in the shipping process. “Broken” simply means there is a slight chip or crack in the cell. But the power produced by the cell is proportional to the surface area, so the chip or crack will just reduce the output. You can buy new solar cells, but these will be more expensive. 4. Materials to Make Your Solar Panel Some material must be bought, the frame and batteries can come from recycled materials. Recycled materials carry the least costs and impact the least on the environment. As a society we create huge amounts of waste, accessing this can take many forms such as recycling centres, for instance wood reclamation yards. In many cities you will find scrap yards and second dealers of glass and plastics. If you can’t find any of the above all of the materials can be found on the street, tatting is fun. But at this point I will put in a boring disclaimer: picking up rubbish from the street can inadvertently be stealing and could be an arrestable offence. Further to this it can be dangerous to collect “tat” from the street due to nails etc. But if you are prepared to take the risk and take steps to ensure the items are not wanted then rewards are high. Skips are great, they contain lots of plastics, glass and wood that are essential in building the casing for the panel. What follow next is a list of materials which relate to the step by step guide of section 5 and where to buy or “recycle” them from: All of the following materials will make a 300watt solar system, scale the items up if you want to build more. Bought Materials: 1) Broken solar cells, either polycrystalline or monocrystaline. Mono are better in terms of efficiency,
they come in either 3x3, 3x6 or 6x6 inches. I suggest 6 x6 as this means less soldering. From www.knowyour planet.com, price for 1kg including VAT = £60. 1 kg will make roughly 300 watts worth of panel. 1kg is technically more like 350-400watt but you will break some for sure. When the cells arrive they might not be complete squares, i.e. they might look very damaged with maybe a 1/3 of the cells broken off. This is ok, their output is proportional to their size. Just make sure you use same size pieces together. More on this later. 2) 80 watt soldering iron ~ £12 also from knowyourplanet. If you get from elsewhere make sure it is 80watt else you will struggle to heat the solder enough. 3) Flux pen ~ £6 also from knowyourplanet. 4) Solder (no iron content) 100g ~ £5 from any electrical retailer. 5) 4m buss bar and 48m tabbing wire ~ £13 also from knowyourplanet 6) 4 x blocking diode (to stop reverse charging from battery to panel) ~ £6 also from knowyourplanet 7) Noncorrosive silicon £6 from knowyourplanet 8) Clear silicon x 4~ £8 you will also need to buy a dispensing gun (£2) – b and q, a pound shop or diy hardware shop 9) No nails glue to put in dispensing gun ~ £4 – b and q, a pound shop or diy hardware shop 10) Multimeter - £6-8 from any electrical retailer or eBay is pretty cheap 11) Wood varnish - ~ £8 (yacht varnish) 12) 100 x 5mm screws 13) 50 small nails 14) 4 meters of 1.5mm2 double core cable, from an electrical retailer ~ 70p per meter (£3)
Other things you will need – An extension cable, a power drill (or muscle and a screw driver) and a saw or jigsaw To Tat: Remember the above disclaimer. You can buy this stuff but it will significantly increase the costs and environmental impact. For the frame and casing: Your probably not going to put all 300watts into one case as this would be a huge panel, better to break down into 5-6 panels of roughly 50 watts each. Large pieces of ply board and glass for the frame of the – you can’t cut glass easily so consider how large you want your panel – transportable? We will come back to this in the construction section. For connection of panel, this guide focuses on the panel itself so this is a brief description: Leisure battery or car battery – leisure battery preferable or even an old railway battery or hospital battery. Car batteries can be sourced for about £5 from any old car garage, leisure batteries are more difficult to find possibly from scrap yards or to buy 90 amp hour = £80-120 from Halfords. NOTE leisure battery are incredibly CO2 intensive, to find a second hand one one rather than buy one is much more in the ethos of this project. However batteries have a limited life time so you might find that the battery needs replacing more often if it is second hand. Some length of 4mm2 double core cable, from knowyourplanet £1.70 per meter. How much you will need will depend on where you place the panels in relation to your batteries. Using thicker cable means less wasted power, use this thickness as a bare minimum as thin cable can melt under high current.
First time round you will probably spend around £140 on materials just because there is a larger outlay first time round but after that I would expect £119 per 300watt system i.e. 40pence per watt. This is assuming you source a second hand battery. 5. Step-By-Step Guide to Construction Ok so you have now sourced your materials. Now comes the fun part. From the outset I’m going to say that there are many small quirks to this that I don’t have the patience or time to go through here but are contained within the workshops. Please feel free to email me and ask questions. Hazards and Risks: please be aware that the 80watt soldering iron is extremely hot when it get going, it will burn your fingers if you touch the metal element. So setup your area with the stand for the soldering iron in a stable position. Second hazard is the glass; if you have tatted the glass it is likely to have shards that will nick your skin so when handling the glass use gloves. First we are going to consider the size of your panel. I’m going to assume you have bought 6x6 (inch) monocrysalline. If you have sourced recycled glass you will be limited by the size of that glass. Ideally you want to make a 17volt panel as your battery will be 12volt. Amps and volts can be manipulated such that you don’t need to follow this ideal, this will become clear as we go through. Each cell has a typical output (on a sunny day) of 0.62 volts, this equates to 27.4 cells to get to a 17 volt panel, let’s call this 28 cells.
So you are saying “but my glass is not the right size at all, I can only fit in 16 cells, I don’t have complete cells, the cells are odd shapes, and you told me to find any old bit of glass”. This is ok because although the ideal size to create the 17 volt panel contains 28 solar cells we can make the panel any size and combine panels together to get the required 17 volt output. Here's how.... Amps and Volts: Amps are the flow of electrons around the circuit, the voltage of the system can be thought of as the energy each electron carries. If you combine cells in series then amps of the circuit remains constant and the voltage increases. If you combine cells in parallel then their voltage remains constant and the amps sum together. Once we have made a solar panel we can combine other panels in series or parallel with the first panel to adjust the volts and amps to fit our requirements. See the diagram below, where we have connected the two panels in series in order to increase their combined voltage to achieve a 17.4 volt panel.
It should now be clear that although there is an ideal size for the panel, you can work with whatever you have. Or in other words this method has been developed such that whatever sized piece of glass you have, you can make a useful solar panel. This will bring down costs and make the panels less environmentally impacting as we are reusing materials. Make sure you do not exceed 18 volts as this will start to damage the battery. If you have a large piece of glass, make multiple outputs such that you are in essence connecting two panels in parallel. Or if have made 2 panels with a combined output of 17 volts and you now want to connect another panel, make sure you do not exceed the 17 volt maximum voltage (see below diagram) in order to increase their combined amps.
terminal of the panel needs to come from the bottom of another cell. It should be noted that the variations in amps is much more dependent on the sunlight that hits the surface of the cells. This means the output of the cells cell in terms of power is proportional to the surface area of the cell. Or in other words if we have half a cells the output will be roughly half. For a complete cell the power output is roughly 3.75 watts, 0.62 volts and 6 amps. Note that power is the multiple of volts and amps i.e. Power = volts x amps. Unless you have a piece of glass with a surface area bigger than 28 cells you won’t need to worry about exceeding the 17volt preferable voltage output.
The reason we have chosen 17 volt desired output is because the voltage output is dependent on the amount of sunlight that falls on the panel. It is unlikely that we are to get a full 17 volts most of the time and we need the voltage to stay above the 12 volts of the battery in order to charge it. If you have broken cells and you therefore can’t assume the maximum output of each cell is 0.62 we need to check what the output of the cell is. The bottom of the cell will be the positive terminal, the top the negative. Skip ahead of this paragraph and look at how to tab the cells. Place a connection on the bottom and one on the top. Now use the multimeter to check the voltage on a sunny day, this will give you an indication as to the voltage output of the cell. We can also take from this that the negative terminal of the panel needs to come from the top of one cell and the positive
I’m going to step back again a little at this point. When we connect cells to cells we will be connecting them in series, in what I call a weave. So when we connect cells together in the normal method we are increasing their volts and the amps remain the constant. This is why we need to have in the back of our minds the voltage of the panel we are aiming towards as we don’t want to exceed the 17 volts. As we are connecting cells in series the smallest cell will limit the output of all the other cells. Hence we must connect similar sized cells together. If you have lots of different sized cells, connect all those similar sized together and then connect different sized piece groups in parallel. See the diagram below:
Because the solar cells are extremely fragile we need to create a ridged backboard. Ply wood is really great, cut your tatted piece of ply to the same size as your piece of glass but 5cm shorter on the open edge. The open edge is where your terminals to the panel will be. This edge is kept open in order to maintain a draft through the panel (keep the cells cool) and such that we can collect condensation build up. This will become clearer latter. At the same time cut the edges these need to be roughly 3cm wide and then as long as the length and width of you panel. So that’s 1 edge for the top, and 2 for the sides. See below....
You now use the screws to secure the edging to the backboard. Screw the edges to the backboard, with the screw entering the back of the backboard first. This enables the backboard to be released later if maintenance to the cells needs to be carried out, see diagram below. Please note that the voltage output of the cells doesn’t drop indirect proportion to the size of the cell as indicated in the above diagram. Ie half a cells doesn’t give half the voltage, it will output more than this. Test the cells in direct sunlight to see for yourself.
the cells to the backboard, rather you are soldering each cell to another whilst they sit on the backboard. This technique avoids having to move the whole line onto the backboard once the line is complete. This needs to be avoided as they will likely break if you try and move a line all at once.
You will need to use enough screws per edge to securely fasten the edging to the backboard. Now you should be in the position where the backboard and edges are all done with the glass waiting to go on, don’t put the glass on yet.
Once the lines are all in place you will then connect each line to each other, we will come back to this. The cells need to face up, this is pretty obvious but I can now refer to the shinny side as the “active” side. Start the soldering process by soldering the back of the cells. This doesn’t have to be done on the backboard, you are going to solder every cells “non active” side first then lay them out on the back board. Look at the diagram below to see what your aiming for the “tabbing” of the non-active side of each cell...
The next step is to solder our solar cells together. Start by laying out a nice comfortable area, preferably inside as the cells are extremely light and thus can be blow by a small gust of wind. You will also need power so sit near a power socket. I am at this point going to assume you have fully formed cells, if your cells are half pieces don’t worry. Simply solder the tabbing wire to as much of the cells anode and cathode as possible. This will make sense as we continue. The solar cells are they are extremely fragile. You will probably break a few, especially at the start. Don’t worry these cells are still useful so don’t throw them away. You are now going to solder the cells together. If you have the ideal piece of glass so can get 28 cells in one panel and have 4 lines of 7 cells then you will solder 7 cells together on the backboard, do another line of 7 and so on. When I say solder them on the backboard board you are not trying to solder
To do this tabbing you need to take the 48m of tabbing wire and for each cell cut 2 pieces of tabbing wire at a length of 31 cm. The overhanging bit, which you can see in the above diagram is to be soldered later to the active side of the next cell. Once you have the two lengths of tabbing wire turn on
your 80wat soldering iron. This will take a bit to heat up, don’t touch the metal element of the soldering iron this will burn you. Whilst the soldering iron is heating up use the “Rosin Flux Pen” to “draw” on the connections. This sentence probably makes little sense. The connections are the 6 white pads on the non active side of the panel. By “drawing” you are putting tiny flecks of flux or solder onto the pads, this will enable the tabbing wire to “stick” to the connections when soldering. Now that the soldering iron is hot and you have applied flux to the 6 connections using the flux pen, take the 2 lengths of tabbing wire, place them along the connections and apply the soldering iron to the top side of the tabbing wire. If this is done correctly there will be a strange smell and the tabbing wires metal coating will melt a little. Once each set of 3 connections are tabbed up leave them for 5 seconds and test the strength of the connection by gently pulling o n the end of the tabbing wire. This whole process needs to be done carefully as in essence you are trying to solder egg shells. When you apply heat with the soldering iron try not to press down too hard on the tabbing wire, this will transfer pressure to the solar cell and cause it to crack or break. As I said before, now you want to tab up each of the cells to be used in the panel (so in this example 28 cells). Now you need to use the noncorrosive silicon. Apply a small amount on each of the bits of tabbing wire where you have soldered the tabbing wire to the cell. You will need to use the dispensing gun to extract the silicon. Use a piece of card to smear the silicon along the soldered piece of tabbing wire. Again this needs to be done with care. This process prevents galvanic corrosion by sealing the connection we are preventing air from touching the connection and therefore the galvanic corrosion process. Once this is done for each of
the cells you are using allow the non-corrosive silicon to dry for an hour or so. If you blobs of silicon are ticker leave to dry for longer. Once this is done place each cell in the first line. Don’t place all the lines down as this will make the process more fiddly. Place the first cell 5cm from the open edge of the ply board with the active side face up and bend the loose bits of tabbing wire so they are not sitting on the back board. This will enable you to then slide the next cell in place... see the two diagrams below.
Note: you need to leave the smallest possible gap between each cell in the line, we have accounted for a 0.5cm gap, this will make it fiddly but this will enable the cells to be secured with the cheap silicon to the ply board. Do the above process until each cell of the line is in place with the tabbing wire sticking up like in the above diagram.
Note that the bottom cell in each line need only have 2cm of loose tabbing wire. Next repeat the flux pen and soldering technique to secure the loose tabbing wire to the active side of each of the cells. This will now form what can be thought of as a weave. The top of one cell is connected to the bottom of the next. What you have just done is to connect the cells in “series”. This means that their amps remains constant and their voltage has summed together. The bottom of the cell is positive and the top side negative so you can see that we have connected positive to negative to positive to negative and so on ... in series. NOTE: If you have cells that are quite broken you want to connect the same size bits of cells together in series, this is because the output of the entire weave will be dictated by the smallest piece, remember the amps don’t sum together in series so the smallest piece limits the entire line. Ok so you have no almost finished an entire line, but make sure you solder some tabbing wire (using the flux pen and soldering iron technique discussed above) to the top cells active side and leave 2 cm of loose tabbing wire just like you have for the bottom cell. Your entire line should now look like the below diagram....
NOTE: if you have half cells or at least not complete cells you may end up with over hanging bits of tabbing wire, as shown
in the diagram below. This can cause a short circuit so snip these off with some scissors. In order to avoid this cut the tabbing wire shorter in accordance with the size of your cells.
Once the first line is completed, repeat for the other lines (in this case 4) but for each next line you must orientate the line in the opposite way to the previous. This is because we are going to connect the lines together in a minute and the weave must continue, so the top-bottom thing. This maintains all cells being connected in series.... see below diagram.
As can be seen in the above diagram, the connection between the 2 lines is by using the buss bar. To do this touch the tabbing wire and buss bar together and heat with the soldering iron. You might find you need a metal object like a knife to hold the tabbing wire and buss bar together as the solder cools and joins them together. Now repeat this process for all of the other lines, this can be seen in the below diagram. Note that each line must continue the weave, bottom to top.
you know how to use a multimeter. If not see guidance on the internet. Take the panel outside on a sunny day with no clouds and test the voltage and amps of the output of the panel. If there is no reading go along each cell testing the output until you find the break. You might now have to replace a cell. The most likely cause will be a bad connection between the buss bar and the tabbing wire. Once you have a 17volt (ish) working panel we can now apply the NONcorrosive silicon to the fronts like we did for the backs of the cells. This time spread the non-corrosive silicon all the way down the tabbing wire on the front. Test the panel again with the multimeter and fix if necessary. In the above diagram the buss bar on the top right and bottom right cells will form the negative and positive terminals of the entire solar panel.
Now take the yacht varnish and apply the varnish to the bottom 3cm (ish) strip of the ply backboard and allow to dry, see diagram below.
NOTE: although I have drawn this orientate along the horizontal, in the original diagrams of the casings this would be vertical. Such that the terminals mentioned above are nearest the open edge of the panel casing. Next take 2 screws and carefully screw through the buss bar of each terminal such that it is secure, the screw doesn’t come through the bottom of the backboard and the head of the screw doesn’t protrude above the height of the edging. Leave the head sticking out. Now take the 1.5mm 2 double core wire and separate the 2 inner cores from each other. Strip back to the bare wire and wrap each copper wire around the top of each nail. Now take the 100g solder and solder the copper wire to the screw. Ok now is the point to test the circuit. Take the multimeter, I’m not going to give directions on how these work, I’m presuming
Now we can start to secure the cells to the backboard (ply). You can do this whilst the varnish is drying. This is done using the silicon and dispensing gun. Because the gaps between the cells are small, use the silicon to carefully and gently apply the silicon in the gaps. This should be done in such a way that
some of the silicon grips the cells. In case you need to replace one of the cells in the future use 4 large blobs of silicon per cell. This will mean that if you need to replace the cell you can remove it without having to remove loads of silicon. Once this is done for all the cells leave it to dry. The dry silicon will hold the cells in place. Next you need to secure the glass to the edging. Take the dispensing gun and use the no nails glue. Apply quite a fair amount along the edging. Spread it out on the edging and ensure that when you place the glass on top the glue won’t be squeezed onto the cells. Before you place the glass on top make sure you have some more wood and rock or brick to hand. Place the glass on the edging and push down to secure. Now take the wood and carefully place on top of the glass, and finally put the rocks/bricks on the wood. This will place pressure on the glass and make sure the no nails glue binds the glass to the wood. You should make sure that at the open edge you have your 5cm gap between the end of the ply board and end of the glass. And that you have the 5cm gap between the beginning of the cells and the edge of the ply board... see diagram below...
Leave the no nails glue to dry for a few hours. Once the no nails glue is dry, find yourself some sponges, cheap ones can be acquired from the pounds shop. Just get kitchen sponges used for washing up. Cut the sponges such that you can stick them between the glass and ply board. They need to be cut such that you fill up the gap indicated by the yacht varnish minus 1 cm....See the diagram below
The sponges should push into the gap and their bottom edge which touches the yacht varnish should not touch normal ply wood. These sponges will serve three purposes. Firstly they air can pass through them such that in hot weather the panels will be cooled a little. Secondly condensation will build up on the inside side of the glass. You will need to orientate the panels towards the sun. Thus the angle of tilt will mean the condensation will run down the inside of the glass and be absorbed by the sponges. The condensation builds up
because there is air in the panel and when the air heat up (night to day) the air condenses on the glass. This absorption of water will need to be monitored. Changes the sponges regularly in bad weather. This will also give you chance to check on the panels and see if any maintenance needs to be carried out. The collection of moister in the sponges also indicates why you must leave the gap between the sponges and the varnish... you don’t want water to collect on the bare ply wood . This will cause the ply wood to root. The third purpose of the sponges is to stop insects crawling into the panels and making a home or leaves and dust being blown into the panel. Water proofing.... This can be done in a number of ways. I suggest you use yacht varnish for the back of the ply board. The most important element to water proof is the exposed edges of the ply with the cheap silicon. Put blobs of the cheap silicon along the edges and smear down the sides with card. Wait for the water proofing to dry and your done. If maintenance needs to be carried out flip the panel upside down and unscrew the screws holding the edging to the back board. This will enable the glass and edging to come away from the glass front such that you can get at the cells. The panel will need to inclined towards the sun and put in your garden. Don’t fix to roofs as you could be liable if it falls off! Inclination angles are not covered here in-depth but a few guides... Latitude – 51.46 (Bristol) Summer - Opt Angle = (latt x 0.92) -24.3 Bristol = 23.04
Autumn and Spring - Opt Angle = (latt x 0.98) -2.3 Bristol = 48.13 Winter Opt Angle = (latt x 0.89) +24 Bristol = 69.80 Once you have made a few panels with different sized bits of glass and therefore different outputs look back to the beginning of this guide to see how to connect panels together in series and parallel in order to achieve the 17volts output. It is advisable to use a charge controller. Charge controllers make sure you don’t over charge the batteries. This is not covered in this guide but are discussed in the workshop course. If you have a charge controller the output of the solar panels should be adjusted (by connecting different panels together) in order to get an output of the panels that suits the input to the charge controller. A charge controller is very good investment, be sure to get a charge controller that can handle the power produced by the panels. No matter if you use a charge controller or not you must now use the reverse biased diodes. These prevent charge from the battery flowing back into the panels at night. Reverse biased diodes should be connected to the positive output of the panels. The diodes bought from knowyourplanet.com will be of around 10amps. Don’t run more than 8amps through them. For ease just connect one diode per panel. A way of doing this is to use a junction box... to avoid cost and reduce the items bought new (reduce our environmental impact) we can use old plastic items such are margarine tubs. You will have to by a few connector block terminals (15amp ones), from eBay these cost around £1.50 for 15. Run the output of the positive into a cleaned out plastic tub and solder the diode to the two parallel connector blocks. Then
connect, using the treaded screws on the connector block terminals, the positive cable from the solar panel the right leg of the reverse biased diode. Then connect another bit of cable to the left leg of the diode. This should all be contained within the junction box. You can now use the other connector blocks to connect other output cables from the panels together and run the cable from the battery (or charge controller) to the junction box. For more information on this please attend the workshop. Post the connection of the panels to the batteries.... Inverter – if you want to crank up to 240 volts.... note I am not suggesting you do this.... after speaking to the building regulation people there is no regulation to comply with for 12v in your own home, but for 240v (more dangerous) there are requirements to adhere to! But ~ £50 for a 200watt one.... note these drain your battery very fast and are not efficient – i.e. you lose loads of energy if you run 240 v Videos showing how the panels are constructed by myself and others in the project will become available on the website (www.DIY-solar-workshop.org) soon. But there are links currently on the website to other people making DIY panels. These videos might not necessarily use the same techniques. DISCLAIMER: You take on the construction of the solar panel at your own risk. Guidelines have been given here but only attempt this if you feel confident in your skills. I, Daniel Quiggin, and the DIY SOLAR WORKSHOP project takes no responsibility for your safety if you follow any of the above text. The most important safety to remember is as follows:
1) The soldering iron is hot and can burn you 2) Recycled glass can have sharp edges, be careful when handling this 3) If you start to combine many panels together the amps will start to become dangerous. Only start to make large arrays (greater than 300watts) if you feel confident with the electronics.
