Making DIY Solar Panels for your Off Grid home
Sarah explains her reasons for attempting to ditch her diesel power generator for a DIY home made solar alternative
I’ve lived on a boat for nearly eight years now, a wide beam canal boat on the Leeds to Liverpool canal. My power supply is a 5kw diesel generator, which is noisy, thirsty, and prone to going wrong on rainy, cold evenings. What is the appeal of applying solar power technology on a boat? Compared to the generator, it is quiet, provides free energy and it keeps on charging whether or not I’m not there to turn it on and off. Most importantly though, it should save me money.
I did investigate the idea of having solar panels when the boat was being built. A salesman, however, said we’d be lucky to get a few light bulbs and a fridge running off them. The money went on the generator instead. But panels have been appearing on many boats in the last few years, even up here in the grey North, ranging from flexible panels which stick onto the curve of the roof to huge solar sails which stand vertical from the roof and can be tilted to maximise the angle of the sun. Following conversations with other boaters, who were all overwhelmingly positive about their experience, I began looking into it again. The first quote for a ready-to-install unit was about £1000 for a 200w system. This cost factor led me to research handmade alternatives.
How to go about building your own solar panels
There’s a lot of information (and, of course, misinformation) online, and many of the forums start from a level of knowledge way beyond mine. If you come across something which seems feasible, it’s still a big step from watching a Youtube video to getting it right in real life especially if, like me, you don’t know your amps from your watts, or one end of a soldering iron from the other. I couldn’t afford to waste time and money getting it wrong.
Then, early this summer, a friend sent me a link to a weekend course. For £150, all inclusive, I could learn the skills and walk away with my own panel. This was what I needed: someone to give me the confidence to just get on with it.
Set in the beautiful rural north of Buckinghamshire, LILI, or the Low Impact Living Initiative, runs sustainable living courses from a converted stable block next to the Redfield Community. We were a mixed group, with little prior knowledge on the subject. Some, like me, were interested in using renewable power in the UK; others wanted to build a knowledge base to take with them on overseas projects, mostly in Africa. One is planning to build a series of sustainable holiday cottages in Thailand. Norman Phipps, the course tutor, works with commercial solar panel installation as his day job, but uses the LILI courses as a springboard to his real passion: taking affordable PV solar technology to communities in Africa with no access to mains power.
The origins of DIY solar
It was while doing an MSc at the Centre for Alternative Energy that Norman came across handmade solar techniques, including the method of laminating or sealing the panels with silicone to give them longevity. The process was devised by Dr. Richard Komp for use in developing countries, and aims to give handmade panels the same lifespan as factory modules.
Norman’s most recent trip was to Tanzania. ‘It’s hard to believe in the UK,’ he says, ‘but some areas of Africa will never get electricity, because it will never be financially viable.’ With support from the Datum Foundation, he takes out the materials needed to build the panels, teaching local inhabitants how to produce units which will power LED lights with rechargeable batteries. ‘The single biggest impact,’ says Norman, ‘was seeing the difference an LED light made to a table of young children doing their homework. We hadn’t been looking into lighting at the time but it made us think that handmade solar needs to be accompanied by handmade LED lights in order to have any impact.’
How to keep it low-cost
On the LILI weekend, we learned how to cut the cells, solder them together and seal them in a ‘sandwich’ of glass and backing with 2-part silicon elastomer. Our A4-sized panels produce 8V in the sun, which is run through a charge regulator to give a steady 5V for charging mobiles or other small electronic items. My next project is to build 18V panels which will charge the 12V lead acid batteries which are already in place on my boat.
The cells we used were damaged cells, rejected by manufacturers due to chips, cracks or breaks. These can be sourced online, for example through Ebay. By reusing rejected materials, energy is saved from the start. Much of the panel can be sourced by recycling, such as old window glass or discarded vinyl flooring. Norman’s advice is to keep an eye on the costs because, ‘like anything, if you don’t shop around for the right material at the right price then it soon adds up. Handmade solar does require time and effort, but if you have both you can save money.’
If you do want to try handmade solar, what are the possible applications in this country? The units are not suitable for houses, such as those you see on roofs utilising the feed-in tariff. They are best aimed at off-grid applications, where they can provide the power to charge lead acid batteries, or to run lighting or charge mobile phones. Norman also recommends using your artistic flair. Glass can be cut into any shape you like: thin and narrow solar panels, panels shaped like a frog or some sort of sculpture for the garden.
I’ve recently built a compost toilet which, so far doesn’t need a vent but I do like the idea of a hand-made solar panel powering the fan for a hand-made toilet. If you’re going to use the power to charge a battery/batteries, you should look for a good quality industrial lead acid battery with under voltage protection (a box that will disconnect the load if the voltage falls below a level).
I’ll be returning once my boat panels are done, with more about how the panels are made. I’ll also be able to report on how efficient my handmade solar is, and how the cost of making them compares to the benefits accrued.
If you want another solar project, take a look at the popular 'How to Build a Solar Power Plant'