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Electronics => Power & Renewable Energy => Topic started by: DC1MC on April 27, 2021, 06:14:04 pm

Title: [DE] Please help and absolute beginner "solarify" his garden hut
Post by: DC1MC on April 27, 2021, 06:14:04 pm
Hello, I'm an absolute beginner regarding PV, but as I've got rid of the gas generator ( that was getting more and more difficult to rope-start by my wife) I've got a lawnmower and some electric bush shears along with some other tools  that has no power source anymore because the garden association totally forbids installing mains power (Germans will know about the strange rules of small garden allotment associations).

Anyways, as I have a little garden hut with a relatively sturdy 2.5 x 5m roof, I'm considering setting a PV installation enough to power a 220V 1Kw lawnmower for 1/2h as it takes to mow the lawn and keep a small fridge cold for the WE.

I was looking around and prices in DE are actually monstrous, in between hiring a landscaping company every two weeks to do the garden maintenance and this+also ordering food in the next 10yrs.  :scared:, who the hell affords this stuff  :-//

And no, nobody will sponsor me "for exposure" or give some stipend  :'(, I have to spend my hard earned cash and no stimulus check whatsoever in DE :(.

So maybe you can price for me the most cheap combo that can produce 220V AND has the parts available in DE (from ali will be in time for winter :)

Many thanks, any help or advice is appreciated.

Title: Re: [DE] Please help and absolute beginner "solarify" his garden hut
Post by: Renate on May 10, 2021, 01:50:06 pm
I have no idea what is available in Germany, sorry.

Here in the US the commodity ~300 Watt panels go for $0.90 to $1.00 per Watt.
A 40 Amp MPPT controller can be had for ~$150
A small inverter for charging is certainly <$200
A fridge is going to take more power/more panels.
Title: Re: [DE] Please help and absolute beginner "solarify" his garden hut
Post by: DC1MC on May 10, 2021, 08:45:08 pm
In the meantime I've got myself a used 175W Sharp ND-175E1F with mounting frame for 90EUR, in (not very bright sun) in the region it produces 5.5A short circuit current, a ridiculous Chinese PWM charger for 15EUR that claims 30A, I've tested it a 5A and seems to hold (see attached picture) and another Chinese ridiculous 30EUR 220V /4000W ( :-DD) converter. Also a nice and new heeeavy 120A/h 12V AGM battery for 150EUR.

The charger allows setting for the most important battery parameters and supports AGM batteries, it has been tested and actually works nice.

I didn't believe at first that either the charger will charge correctly according with the set profile, or the converter will work with my garden tools (an 800W lawnmower, an 1000W garden vacuum cleaner, an 1200W chainsaw and 300W shears for bushes), but actually they work nicely and the battery fully recharges in a sunny day or two typical German days, considering that I mostly use stuff once or twice a week, it suits me well. I was pretty distresses at the beginning because I didn't even know which is which and looking at enormous prices, but in the end , for my little garden shed, a laptop, access point and week-end garden work it seem that is enough.

So except for the battery and the brand name panel, that I've tried to get the most bottom of the barrel cheap crap that I could get on with it, expecting it to produce smoky fireworks, or not working, but to my pleasant surprise, they kind of work as intended for my modest needs, so the Victrons and 3.00EUR/W LGs will have to wait a for bit ;D, maybe when I'll have my own house and whoever comes in place of Angela will give us again some solar subsidies.

I have replaced the fridge with a cooling box of 48l that should arrive soon, I only need it for keeping the food and drinks cold for a while when I'm grilling in the garden with family, no permanent cooling is needed, my battery should support 48W at full charge for a few hours.

This is how I'm starting my solar journey on my little 320 sqm garden with a little shed.