My OFF-GRID 880W installation in a single-family house - independent of the ener

Hello,
after many months of analysis, reading various topics on the forum and drawing conclusions, I managed to fulfill my little dream, which was to build a (partially) independent, automatically controlled OFF-GRID photovoltaic installation :)

My assumptions were as follows:
- supplying energy from PV panels during the day to receivers operating during the day (power supply for pumps and heating controls, cameras, alarm, modems, recuperation, fridge ...) - total power consumption is 200-250W
- storing surplus energy in batteries to be able to use it on cloudy days
- automatic switching of specific circuits between PV and the power industry, if no electricity flows from the PV installation

My installation consists of:
- 2 Longi panels with a power of 440W one
- Epever Tracer 4210AN charging controller
- AGM batteries operating in a 24v system with a total capacity of 1.4kWh
- 3000W pure sine inverter (1500W continuous power)
- fuses, measuring devices, etc...
- double-circuit relay switching circuits between photovoltaics and the power grid

The installation consists of 2 Longi panels with a power of 440W each, mounted on a woodshed in the east-west directions:


Everything is handled in my little command center Of course, I used the appropriate safeguards:


From here, the current goes to the switchgear in a single-family house, where it controls a relay that switches specific circuits of receivers to power from photovoltaics (if the voltage from my "power plant" flows), instead of the power grid. Similarly, if my home "power plant" is not working, it is automatically switched to power from the power grid.

I plan to replace the batteries with LifePo4 from China with a total capacity of 2.4 kWh :)

So far, the system works great, unfortunately I am not able to store the entire surplus of electricity, because so far I consume about 1.2 kWh / day, taking into account that for the protection of the batteries, an automatic device is set to provide voltage to the house only in the hours of 7: 00 - 18:00. After replacing the batteries, I plan to power the house 24/7 with PV.

Below is a video where I briefly discuss the operation of my system:

Kubik26 wrote:

After replacing the batteries, I plan to power the house 24/7 with PV.

with this kit?

Kubik26 wrote:

- 2 Longi panels with a power of 440W

ADB-6 wrote:

Kubik26 wrote:

After replacing the batteries, I plan to power the house 24/7 with PV.

with this kit?

Kubik26 wrote:

- 2 Longi panels with a power of 440W

Exactly Power consumption by the above-mentioned circuits is about 200-250W.

Why on the shed and not on the apartment building? What about batteries in winter?

cysiekw wrote:

Why on the shed and not on the apartment building? What about batteries in winter?

For me, installing panels on the roof of a new house is aesthetic barbarism
In winter, I plan to insulate the battery, or put it in the ground, similarly to road power.

And for me, a sign of the owner's awareness and improving the aesthetics of the building because many new houses are tasteless and 4 meters from the border on each side.

I don't understand why not take advantage of the on grid on the currently best conditions that can be, soon they will only get worse and such a combination will become a necessity.

Did you count how much this installation cost you or is it just a hobby?

stomat wrote:

Did you count how much this installation cost you or is it just a hobby?

I treat it as a hobby, but roughly:

- Charging regulator PLN 490
- Control panel for the regulator - PLN 85
- Inverter PLN 480
- 2 panels PLN 1,200
- recycled batteries (PLN 200 for 12 V 120 AH)
- Fuses ~ PLN 100
- Wires, relay box, meters, etc. ~ PLN 250

It comes out to about PLN 2800. Assuming that the panels will produce 2 kWh per day (which is easily achievable) at the gross electricity price of PLN 0.70, this gives annual savings:
2*0.7= PLN 1.40 per day
1.40 * 365 = PLN 511 per year

Apart from the consumption of the batteries, the entire installation should pay for itself after about 5-6 years, but I didn't build it mainly to save money, and I was irritated by temporary power outages and thought I could do something "my own" ;)

I would like to add that I plan to invest PLN 1,600 in new batteries, but it will take some time.

Hello!
But you can't avoid fixed costs with ZE anyway.

CKCK wrote:

Hello!
But you can't avoid fixed costs with ZE anyway.

If I expand with the appropriate power, I will avoid completely resigning from ZE services On the other hand, fixed costs are also a problem for owners of on-grid installations.

My fixed ZE costs per year are PLN 100.
Make the whole house on OFFGrid, then we'll talk. For now, you've made installations for a small crib, survive the winter on this offgrid and we'll talk next year ?

God forbid I don't criticize you for your performance and willingness but life is not Netflix and we live in Poland, not in sunny California ?
December / January there is practically no sun and it's like Akku dies, I know because I experienced it myself and also at the beginning I thought about offgrid everything but luckily I cured myself ?

Leon444 wrote:

My fixed ZE costs per year are PLN 100.
Make the whole house on OFFGrid, then we'll talk. For now, you've made installations for a small crib, survive the winter on this offgrid and we'll talk next year ?

God forbid I don't criticize you for your performance and willingness but life is not Netflix and we live in Poland, not in sunny California ?
December / January there is practically no sun and it's like Akku dies, I know because I experienced it myself and also at the beginning I thought about offgrid everything but luckily I cured myself ?

I would not be so optimistic about this ZE, since in a moment they will decide how much electricity they will take from you Not to mention the constant price changes, including fixed fees.
As you rightly pointed out, I haven't made a large installation since then, to treat it more as an experiment with expandability.
As for the battery, as I described it, my system decides that there is always an adequate reserve in the battery, I think that if I change the AGM to LiFePo4, the durability of the energy storage will improve even more.

As I wrote, the problem with OffGird is that there is no sun in the ground and the battery dies and in the summer there is too much of it and after charging the battery the energy from the panels is not used.
With this ZE, you never know, of course, but with gas for cars they have also been saying for almost 30 years that it will not pay off because the price will change soon and it is what it is

Leon444 wrote:

As I wrote, the problem with OffGird is that there is no sun in the ground and the battery dies and in the summer there is too much of it and after charging the battery the energy from the panels is not used.
With this ZE, you never know, of course, but with gas for cars they have also been saying for almost 30 years that it will not pay off because the price will change soon and it is what it is

The issue of profitability is a completely different matter
In any case, you are certainly right that there may be a shortage of power in the winter. I also take this into account, for now I'm thinking about some alternative source of energy, it blows quite strongly in my localization, maybe I'll try some windmill of my own design, or some other system, I like to experiment, so I'll definitely be up to something I probably won't completely cut myself off from ZE, but at least I'll try to produce as much as I can.

Kubik26 wrote:

The issue of profitability is a completely different matter
In any case, you are certainly right that there may be a lack of power in the winter. I'm also considering this, for now I'm thinking about some alternative source of energy

An alternative is to oversize the PV installation, and so that the energy is not wasted in the summer, you use it to heat the DHW, in the winter, when the hot water is from central heating, you load all the energy into the batteries, and what is left, to the boiler.
I started from the other side, first there was an off-grid 2 kW water heater, then batteries with a UPS for home emergency power. Now I will make lighting in several rooms on 12V to avoid losses on voltage conversion. I also have an on-grid 3 kW, in winter there were rarely days that it was less than 1 kWh. With modest use of electricity from the batteries, I am not afraid that they will be discharged.

Kubik26 wrote:

that the panels will produce 2kWH per day

On a cloudy or rainy day, they give you as much as you write because I don't want to believe it.

My off-grid cost about PLN 4,000. I set up a counter on the heater for the boiler and from 15.05 to now, because the temperature is 72oC and sonoff cut off the power to the heater, and I have 20.6 kWh. It turns out that in 4 rainy, cloudy days, the heater saved me PLN 14.6 and I had warm water in the boiler. In addition, the 230V converter used from 15.05 to now 5.68kWh, which gives PLN 4, so for these 4 days, or if you prefer 5, I have saved almost PLN 20. It seems to me that for an off-grid in bad weather, the result is not bad.

Kubik26 wrote:

and I was irritated by temporary power outages

Just like a friend writes an interesting movie on TV or a match and here's a slap (deaf and dark) and it motivated me to build my off grid, which over time grew without any partnerships with Taurons or similar.

As for those unfortunate batteries. After all, it is not said that you have to roll them from morning to night. Mine work only during the day and practically buffer and not cyclically. One hour before dusk, the converter is powered only by the power grid. What the inverter plus the heater will process from morning to dusk is enough for me. In the event of a power outage, no matter what time of day or night, my 3 batteries are 100% charged and ready for action.

Kubik26 wrote:

that I can do something "my"

Go on buddy

@anaba255 are you sure you have 3kW installations? Is it 30kW? Because I have over 10kW and in December it was bad and often below 3kWh and sometimes below 1kWh.
And this is December alone, but where is November, January and February? Which this year was also very, very bad.

Leon444 wrote:

anaba255 are you sure you have 3kW installations? Is it 30kW? Because I have over 10kW and in December it was bad and often below 3kWh and sometimes below 1kWh.

I wrote that it was rarely less than 1 kWh, this does not mean that it was often much more. I have an installation at a small angle of 18°, the advantage of this arrangement is more even production, when it is cloudy the panels collect more energy from diffused light. In addition, single crystals like the cold.
Just out of curiosity, at what angle do you have the panels and what kind?

I have panels at a different angle, but the vast majority are at about 30 degrees, the rest are different, e.g. 40 degrees 2.4 kW, with 9 kW to the south and the rest to the west.
As you can see on the chart (I have these charts from several years), the entire production for December is less than two good days in May.
That's why offgrid makes no sense in our climate...
In December, every now and then I had to charge the Akku from the network and in May / June at 12 noon the panels did not work because the Akku was charged.
I miss a nice saving in the winter and in the summer 70% of energy goes to the "whistle"

Leon444 wrote:

That's why offgrid makes no sense in our climate...

Once I read an analysis of the ground and it turned out that in the Polish climate a wind turbine with a capacity 50% lower than the panels will produce the same amount of energy during the year, so hybrid solutions are probably worth considering.

Leon444 wrote:

In December, every now and then I had to charge the Akku from the network and in May / June at 12 noon the panels did not work because the Akku was charged.
I miss a nice saving in the winter and in the summer 70% of energy goes to the "whistle"

These 10 kW worked off-grid?
How many batteries did you have and how many of them were you charging?
For me, the assumption is different, the priority will be energy consumption on a separate circuit, where there will be a small consumption, the rest in the boiler. In summer most of the energy will go to the boiler, in winter vice versa. Batteries will be virtually undischarged, except in emergencies. I have a large boiler, 350 L, and it has never happened that the regulator turned off the power to the heater, although the temperature on sunny days reaches 70 ° C, there is a supply of hot water for cloudy days.

I'm 5.2 degrees west. He gets up at 6:10 to work, the inverter is already working from the panels (start when the batteries have min. 13.8V at night, resting 12.9V), the heater somehow fires around 7 (start min. load 17A).
I tested the boot on 6 panels 5.2' west and the same 6 panels 35' south ... my decision to the west was flawless.
Winter (if the panels are not covered with snow) or summer, it seems to me that it makes good use of its off-grid and I see no point in not having it.
It is important how the Euro will be so that some power plant like Bełchatów does not fail

The second part of the film about my installation was created. I also raised the issue of why the MPPT regulator is better than PWM :)

Kubik26 wrote:

stomat wrote:

did you know how much this installation cost you or is it just a hobby?

It comes out to about PLN 2800. Assuming that the panels will produce 2kWH per day (which is easily achievable) at the gross electricity price of PLN 0.70, this gives annual savings:
2*0.7= PLN 1.40 per day
1.40 * 365 = PLN 511 per year
.

2kWh per day is probably an exaggeration. While in the summer it is achievable, even about 2 times more, in the winter the efficiency of the panels drops drastically. Even

I invite you to watch another video with a small extension of the installation and a few comments.

Everything is very nice, it's nice to read and watch, but the assembly on wood worries me Put it in some steel switchgear

The whole thing is screwed to plexiglass, only I can't see it at first glance I do not have high voltages here, only 44V in addition to protection and a fuse, very low risk of high currents.

I also thought about off-grid and I even have a huawei with a battery input, but somehow I don't see it.

And would it be possible to build an installation even without batteries. Simply, when it is sunny, the electricity flows to the installation in the house (even to the part under one fuse) and when the panels are not working, the contactor switches the power supply from the mains. Batteries do not necessarily have to be, I mean mainly to reduce electricity bills. Is a colleague able to present a diagram of such an installation of elements for "green" because I am at the beginning of the road with photovoltaics

The easiest way is to locate the wires coming from the meter in the electrical switchboard and unscrew them from the installation, of course remembering where the neutral wire N (blue) and the phase or phases (brown, gray and black) were screwed.
These wires should go to the hybrid inverter. It is an inverter that has a battery charger (regulator) and a 230V inverter.

To the IN 230V AC input. If you have 3 phases, the matter becomes complicated because you will need a three-phase inverter or three inverters working in parallel (cheaper option).
You will also have a 230V AC output from the inverter. And from it you lead the wires that will return to the places of those previously unscrewed.

At this point, your entire home will be powered by an inverter. You connect batteries and photovoltaic panels to the inverter.

That's it in a nutshell. Playing with some separate power cords through the inverter and other alpine combinations is just a makeshift.