Balcony PV "powerplants"

[Buddahaid]

I have no idea about power where you live but connecting alternate power sources to your house requires some sort of switching for safety. If you have a gas generator large enough to power the house you would need to disconnect from the power grid before tying in the generator, or have an expensive transfer switch arrangement that handles that automatically. It's needed to handle phase problems etc.

I simply unplug my fridge from the wall and into an extension cord from the little generator running outside when needed.

Solar panel systems also use some type of transfer switching arrangement but I don't know how those work.

[Rockstar]

Im not certain how one connects a solar panel to household supply.

But I have used them on a sailboat. For strictly 12 volt system lights and appliance . Add up the total number of amps you will be using and for how long each day. This determines the minimum wattage of the solar panel required and the size of your battery bank.

We added two 185 watt panels to our 600 amp hour battery bank and we never lacked. It powered our propane refrigerator, propane heaters and stove, navigation equipment, RADAR, radios, lights. More than we needed.

To run household appliances such as coffee makers, blenders, etc etc you only need a modified sine wave inverter. But for sensitive electronics like TV’s PC’s you should invest in a true sine wave inverter. Which every inverter you choose either one will place a massive drain on the 12 volt battery bank and charging system. So TV and PC are not something which can be run regularly. Unless you have a lot sunshine and many many more panels.

Then there is the the issue with batteries. Car batteries won’t do, you need a Deep Cycle battery and they all to some degree vent explosive gas when being charged. So good ventilation is a must.

That’s all I can think of right now.

[Skybird]

There are startups, from austria for exmaple, where the panels get connected to some directioning device or inverter, and that device gets linked to a battery/storage and gets plugged into a usual wall mount already existing everywhere in the apprtment/house, a usual wallmount where you usually get electricity out off, you have your TV and PC connected to it for exmaple. But here, the direction gets reversed, you do not drain power from the wallmount, but you stuff it into the walmount, from the solarpanel and inverting device and battery into the circuit of your house cable circuit, and then you have it available at other wallmounts on the same circuit. Its a plug and play solution, and is simple to attach indeed, you have the panels placed, connected to the inverter or what the device is, the device goes to a battery, the battery to a wallmount, and thats it.

I did not believe it, too, until i read about it this weekend.



Question is whether the economic usabilitiy and the costs for especially the battery, calculate well.



I look for something smaller, maybe. I have no electric heating and electric hot water, am more interested in beign able to reliably recharge batteries, maybe run a refrigerator, or just a light bulb or two. So I more likely am looking for a setup like this: solar panel to a cable-connected mobile battery with inbuild inverter (if that is how its called, I am not sure, the German word is I think Wechselrichter), and some mounts in it for various plugs.










In Austria you can feed back 500W into a wallmount and circuit legally, in Germany 600, and an EU norm even mentions 800W. However, in this case you need to repalce your electric meter if it is a Ferraris meter with rotating disk in the display, becasue that disc would start to rotate in opposite direction if the solar device/batter starts to feed into your circuit. Since these solutions due to thew battery are already a bit expensive (2000-3500 Euro), the costs mount up if you want to replace the electric meter as well.


For Germany: https://machdeinenstrom.de/sind-mini...ftwerke-legal/

[mapuc]

I would recommend you to buy a battery with a higher capacity, well buy a couple when you're at it.

It's not how many watts you put into the wall socket it's all about voltage-In Europe it's between 220-240 V.

Your inverter(=Spannungswandler) should have this as output.

Markus

[Skybird]

From my ebike battery I know that the storage capacity is measured in either Wh, or Ah.

1Wh = 1Ah x 1V

My Bosch powerpacks for the bike for example have 500 Wh each, at their output of 36V that means they have 13.9 Ah. If the batteries would have an output of 12V, it would be 41.7 Ah. Its not enough to know how much "load" a battery can hold, you need to also know at what power (V) the consumer is running.

With solar panels, their specs influence how much energy they create at a given sunshine level, and over what time. Obviously this decides how fast the battery creates a charge.

I do not want to go for a solution that feeds into the existing wallmounted circuit. A battery that can support one or two light bulbs or a ventilator directly, occasionally a recharging of powerbanks or mobile devices, and maybe run a refrigerator via cable extension, would be good enough. I am not planning to go eco power here, I want a backup solution as part of my prepping for emergency situations. The threat of blackouts is somethign that in all secrecy is starting to worry even German authorities, it is rumoured. A blackout of just an afternoon, that is one thing. A blackout lasting for several days - that is something very different due to the long lasting aftermath from that: could easily become weeks. Therefore, i have started to check and resupply my supplies of everything, and have increased my stocks of drinking water. I also have gotten sacks of charcoal and wood for my rocket oven, for cooking

Running an electric heater I have ruled out, since I think that is a hopeless task with such batteries. When do you heat? In winter. And what do you not have in winter? Plenty of sunshine.

[Rockstar]

So if remembers correctly, a 800 watt inverter divided by 240 euro volts would provide 3.3 amps. Then we reduced that by 10% because of connections, length of wire runs and other mysteries. This gives you an idea what can be powered.

Say you use a 12volt deep cycle battery with a 105 Amp Hour rating. Which means your battery will be as dead as a door nail in 105 hours at 1 amp per hour.

To determine the minimum drain on your battery the inverter causes when pushing 3.3 amps (full output). Take 800w divided by 12 volts and that inverter is drawing a minimum of 66 amps an hour. Something like that will only give you a little over an hour of use at full output before your battery dies.

Two 400 watt solar panels and a lot of clear sunny days ought to keep things going quite nicely.

If it’s a 24 volt battery it gets better.

At least I think so, I could be wrong I haven’t had to mess with 12 volt stuff and inverters for 20 plus years

[Skybird]

Thanks for showing me my huge deficits...

[Platapus]

The Frau invited a Solar salesman over to our house. Yikes!, what a sales job. He was actually pretty good at the sales talk.



But there was only one definite number in all his calculations.


$36,000 to have his company install it.


The best way to get solar for your house is to buy a house that already has it installed where the seller has already taken several baths on the "investment"


$36K and we live in a small triplex!


That was a big bowl of Nope with extra Nope sauce on the side.