DIY Solar Cell Panels

[Laurie Forbes]

Since discovering (thanks to this forum) sources of inexpensive cells, I'm v interested in making my own panels. It seems easy enough but one question I have in particular concerns the grid-tie inverters available on ebay etc. such as:

http://compare.ebay.com/like/200541768307?ltyp=AllFixedPriceItemTypes&var=sbar

These are pretty cool as you apparently just plug them into a wall socket, and, they can apparently be stacked, but I wonder about electrical approvals for this made-in-China stuff. I emailed one vendor who stated only they have "CE" (approval I guess) for Canadian markets. Does anyone know what exactly that means and if it would be permissible to use such a device here? I'd be mostly concerned about the auto-disconnect on grid loss.

As far as making the cells, here's a vid from an ebay vendor that look like a good way to go. Anyone here tried it or something similar?

http://cgi.ebay.com/Solar-Panel-Frames-for-diy-using-36-3-x6-tabbed-cells_W0QQitemZ180476303115QQcategoryZ41981QQcmdZV iewItemQQ_trksidZp4340.m8QQ_trkparmsZalgo%3DMW%26i ts%3DC%26itu%3DUCC%26otn%3D5%26ps%3D63%26clkid%3D8 020689507252537067

One other thing - Rob mentioned $2/W ready-made panels now being available but I cannot find a source. Any URLs one could look at?

[Ralph Day]

Laurie
If you want to explore this further follow this link (sorry Rob, it's to the NAWS forum). It's pretty extensive in it's coverage. No need to re-invent the wheel.

Short answer...keep away, keep very far away!:eek:

http://www.wind-sun.com/ForumVB/showthread.php?t=10745&highlight=plug+grid+tie+inverters

Ralph

[Rob Beckers]

To echo Ralph's link: They're not legal. There is no legal way to hook up an inverter to an outlet. Code requires AC and DC disconnects and a whole slew of other details. I even wonder about that CE listing; this is a European norm (to the best of my knowledge it's self-certified, but the assumption still is that the device complies with the rules). Over there it's equally illegal to hook up an inverter to an outlet, so that CE listing is probably fake.

I'm not worried about electrocuting a line worker by backfeeding the grid when the power is out, a small inverter can't shoulder the loads needed for that. The biggest risk would be that the thing goes up in smoke and takes the house with it.

Grid-tie inverters are unfortunately not cheap (cheapest one I have for sale is $1,898 for a 3kW PV inverter).

As to $2/Watt modules: Yes, they're available. My sources are a bit different from regular retail, and I don't want to put them on a public forum, but a little searching with Froogle will turn them up. Here is an example of Canadian Solar for $1.89/Watt. (http://sunelec.com/index.php?main_page=product_info&products_id=750&zenid=db5edd2d5747b64fbf771ac4e0b5d7ce) Canadian Solar is a decent middle-of-the-pack brand.

-RoB-

[Laurie Forbes]

Gentlemen, thanks for the cogent comments. I had realized at one time that anything directly from China that plugs in should probably be avoided as CSA is unlikely so thanks for the reminder. It also had not occurred to me that line overload could happen with a plug-in inverter (unless a dedicated circuit was used). It was a vendor in China who told me it has CE approvals. I also queried an ebay vendor in the US but haven't heard back.

Thanks for the pointer to the ready-made panels. At those prices, DIY doesn't look like much of a bargain alright.

[Dave Turpin]

Trust me when I say that trying to make more than one or two panels yourself is a huge pain. And good luck passing an electrical inspection. I have a couple small ones I made myself that keep my sump pump battery charged. So they're effectively off-grid. (They also will power some DC emergency lights when the power goes out, but I haven't finished that wiring)

I also had an aborted attempt to make some big 240W panels. Too many things can go wrong when you are soldering 60 hair-thin wafers together and then trying to epoxy and lay glass over them. Like having a dog knock them over, shattering the wafers.

The eBay inverters are an enigma. eBay is chock full of them, but for the life of me I cannot imagine where the original source of the devices are. They are illegal to install basically anywhere. Maybe they are popular in China, and there are fewer regs? Any company that claims a CE or UL listing on the things are blowing smoke.

[Joe Blake]

I'm not worried about electrocuting a line worker by backfeeding the grid when the power is out, a small inverter can't shoulder the loads needed for that. The biggest risk would be that the thing goes up in smoke and takes the house with it.

-RoB-


Just thinking. If one had a grid-tied system with a large inverter (with the required automatic grid isolation), and then the small inverter (running off a battery) was plugged into the household circuit (assuming the grid was down for whatever reason) then wouldn't it be possible that the small inverter would act as an "exciter" circuit to fool the isolating hardware into believing the grid was actually live, and consequently feed the entire output of the domestic system back into the grid? :eek::eek:


Joe

[Rob Beckers]

No, won't work Joe.
The small inverter would first have to power the rest of the neighborhood, get the voltage and frequency up within the limits of the grid-tie inverter before it would kick in. It just can't do that.

-RoB-

[Dave Turpin]

Also those eBay inverters will not work without grid current. They will shut down, too. Now, the inverters designed for RVs... Would work if you first opened your mains breaker. Maybe.

[Joe Blake]

Now, the inverters designed for RVs... Would work if you first opened your mains breaker. Maybe.

And removed all loads on the domestic circuit?

But even if it did work, then the moment the load exceeded the capacity of the grid tie PVs then the whole thing would possibly collapse, and you'd have to go back and start again.

You'd probably need to have the output from the PV feeding into a largish battery bank to smooth out any power fluctuations then ANOTHER inverter to run your appliances.

Sounds a bit complicated.

Joe

[Jack Martin]

If you have ever had an interest in using alternative energy sources then DIY solar panels may be just what you’ve been looking for. Learning how to build a solar panel is actually much easier than most people first imagine. Without a doubt, DIY solar power is an inexpensive and environmentally friendly way to generate electricity for the home.

[Paloma Jack]

Most of the people said that solar panel power consuming. But in day time we can a power while in night what can we do. Solar Power is expensive too. I don’t know how to make solar panels.

[Dave Turpin]

Solar has a high start-up cost but almost no maintenance cost. This is why any installation has a calculated "pay back" period, between 5 and 30 years depending on the savings. The shorter pay back times are for feed-in tariffs, where the utility pays you for each kWh produced (even if you use it). Very few states and terriories have these tariffs.

At night, you either use power stored in batteries (standalone) or power from the utility (grid-tied), and the idea is to produce enough power during the day to completely offset your usage.

Now, making your own panels is a fun project (I have a few experimental panels running small DC loads) but it is not economical in these times of $2/Watt panels (especially since you cannot hope to receive feed-in tariffs with DIY panels)

[Nelson Nacita]

Hi I am new to this forum so bear with me. I am looking for a company who will install solar panels on my roof, can somebody recommend a reliable company. Also, if possible I want to be directly involve in the construction. Thank you.

[Joe Blake]

Hi Nelson,

Welcome to the forum. Which city/state do you live in?

Joe

[Nelson Nacita]

Hi Joe,

I am living in Mississauga, Ontario, Canada.

nelson

[Dave Schwartz]

My installer, Natural Power Products (http://www.npp.ca), says on their website that they will work with you on whatever aspects you need from parts-only to a turn-key system and anywhere in-between. Although they're in Brantford, Mississauga is certainly in the area they would cover.

Of course, warranty terms and ease of obtaining inspections will vary based on how much and where your unlicensed input occurred. For example, an electrician is unlikely to warrant any materials they did not supply or connections they did not make and an inspector is likely to go over the system with a fine-toothed comb if he is not already familiar with that person's work (e.g. our 'inspection' took about 5 minutes - the inspector had already seen several systems my installer had done... its called trust and respect and has to be earned).

[Joe Blake]

And removed all loads on the domestic circuit?

But even if it did work, then the moment the load exceeded the capacity of the grid tie PVs then the whole thing would possibly collapse, and you'd have to go back and start again.

You'd probably need to have the output from the PV feeding into a largish battery bank to smooth out any power fluctuations then ANOTHER inverter to run your appliances.

Sounds a bit complicated.

Joe


A couple of weeks ago, a fairly big storm front swept through the southwest of the state, taking about 170,000 houses off the grid (including mine) for about 24 hours. However, with a combination of batteries and a pedal powered generator (Windstream) on my bicycle trainer I survived quite happily, watching TV, recording DVDs etc.

Then a couple of days later, my 15 year old 240 volt fridge died (don't know if the two events are connected) and I had to buy a new, much more efficient one. Local laws require that if an old fridge is to be dumped it must be de-gassed by a qualified electrician, and I wanted to make my dead fridge into a raised vegetable garden, so I called in a local 'leccy to perform the autopsy.

Interestingly, in the course of conversation while the de-gas was under way, we talked about the power outage and quite unprompted, he said that if it happened over a longer period (not just 24 hours) he was going to do exactly what I had thought in order to harness my rooftop PV panels. ie disconnect from the grid, plug a battery powered inverter into the domestic circuit to trip the cutoff and then use the PV power.

Hmmmmm. V-e-e-e-e-e-e-r-y interesting.

Joe

[Joe Blake]

Even more interesting when considering this item in the news page of the forum.

http://www.renewableenergyworld.com/rea/news/article/2012/07/utility-works-to-unlock-smart-grid-potential-of-solar-storage?cmpid=rss

Joe

[Rob Beckers]

There are (and have been for a while) several plug-and-play products that provide battery storage from a PV charging source, for backup power during a power outage. Trouble is that they are expensive, and the batteries need to be replaced even if they were never used. Batteries wear even if they just sit at float charge.

For northern Europe (I grew up in the Netherlands), a grid outage is so rare that it's just not worth investing in backup power. For North America, where outages are far more common, they are still rare enough that dedicated battery backup is a poor investment. For the once or twice a year they happen (on average) people are just better off with a backup generator (much as it hurts me to say that, being in the RE business).

The other part is that the average North American household has such large loads that taking even a subset of critical loads to battery backup requires a large investment in batteries (which need to be replaced after 3 to 20 years, depending on type and quality of the batteries). Forget about running the A/C or electric range on batteries...

In short, while I think that the idea is a good one, it is not a practical one until the average household uses far less energy than it does today, and better battery technology comes along.

-RoB-

[Jane Penny]

When you say inexpensive, how much is it? I've recently become a home owner and would like to go greener buy growing my own fruit, vegetables, herbs but also gather my own energy! In a slightly unrelated note I now work part time instead of full and so have a little bit of time to do research and tend to my garden, and stumbled upon this forum! I'm an amateur in every sense of the word in this area, so you can be as patronising as you like, I need to be told! Initially I was going to head over to this place that does commercial solar panels (http://www.aandtsolar-electrical.co.uk/) (as well as domestic and caravan) but I'm warming to the idea of a bit of DIY. Is there a handy guide out there for me, or can you guys give me some start tips?

Thanks!

[Rob Beckers]

Welcome to the forum Jane!

I assume you're talking about inexpensive PV cells to make your own solar panels? Unless you want to do this as a learning experience, with little hope of making a useful panel that will hold up outside for very long, I would suggest just buying panels ready-made. Since the start of this thread, a year and a half ago, prices have dropped in half. In the US one can find decent brand-name panels for $0.65/Watt these days (here in Canada it's around $1/Watt now).

It is very difficult to make reliable PV panels as a DIY project. It's very difficult to make ones that actually work in fact. The cells are very fragile and break easily, the materials needed are hard to get and difficult to work with. Financially it's not worth it any more.

In any event, solar panels are just a small part of the puzzle when it comes to powering anything with home-made electricity: The panels are normally hooked up to a charge controller, the output of that goes into batteries. From there you can run 12 or 24 Volt appliances directly from batteries, and/or hook up an inverter and create your own local electricity grid for powering regular 240V appliances (I believe that's the voltage in Britain?).

-RoB-

[Jane Penny]

I don't have time to properly read this through but thanks for your quick reply, I'll come back to this after work!