italianuser
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- Joined
- Feb 25, 2020
- Messages
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Hi there everyone, I'm going into details with the project for my new low-budget solar system.
I need some help to understand pros/cons for the inverter, I did some research but this is actually new for me. My first system was a good experience for me, a small 12V system, 4x 50W panels, 20A regulator, 1500W inverter; now the new system could be 24V (I also examinated a 48V system, it seems to me that my specs are at limit between a 24V and a 48V system, am I right?).
After some analysis I arrived to something like this (my wife simulated fainting when I told her total expense was 1500€, not much really, 1EUR=1.20USD ):
Plus, what I don't like of offgrid inverted is that batteries are charged from grid also, do tell me if I got it wrong, but it seems inefficient to me to charge DC batteries to then convert it again to AC to give current to the house. If this is what happens I think I'd prefer to have separate inverter and charge regulator and avoid charging batteries from the grid, controlling power source switching in some other way.
TIA
I need some help to understand pros/cons for the inverter, I did some research but this is actually new for me. My first system was a good experience for me, a small 12V system, 4x 50W panels, 20A regulator, 1500W inverter; now the new system could be 24V (I also examinated a 48V system, it seems to me that my specs are at limit between a 24V and a 48V system, am I right?).
After some analysis I arrived to something like this (my wife simulated fainting when I told her total expense was 1500€, not much really, 1EUR=1.20USD ):
- 4x 280W 60 cell class A poly panels Voc 39.0V Isc 9.27A in 4s1p configuration, total 1120W (will become 6 panels later, total 1680W).
- 4x 100Ah AGM 12V batteries in 2s2p, total 200Ah 24V (could go for 4x 120Ah 2s2p, total 240Ah 24V).
- Offgrid Inverter 60A 3.2KW (when I started searching I was first looking for an 6000W inverter and an 80A solar regulator, two devices, but offgrid inverted seemed more suitable).
- Noise: They seem to be quite noisy so I couldn't keep it inside (I have a sort of big open space room), so I could consider keeping it outside on the balcony. Temperatures in winter barely go below 0°C and in July/August normally go up to 40-42°C (104-107°F). I would use an external ABS enclosure, and support some efficient temperature control.
- Hybrid: would I really have any advantage using a hybrid system? Considering I don't want to give electricity to grid.
- KW requirements: House requirements for electricity are normally quite low, well under 2KW, with not-so-often higher peaks of 3KW for maximum 30-60 minutes per time (oven, kitchen appliances). I'd go for 3.2KW inverter model although I don't like to be at specs limits... I had a look at 5KW, too, but it's 48V. In this period I'll be monitoring house KW usage for a more detailed insight on peak loads. My current usage is 220-240KW/month (7-8KW/day average).
- Make/model: yes, I know that I shouldn't look at cheap products, but budget wins over everything. I was looking at models like Powland SMR 3.2K 24V (very similar to Easun and PowMr products) in the 300-350€ range. https://www.aliexpress.com/item/33024632564.html. If you tell me these are not reliable I'll rethink the thing.
Plus, what I don't like of offgrid inverted is that batteries are charged from grid also, do tell me if I got it wrong, but it seems inefficient to me to charge DC batteries to then convert it again to AC to give current to the house. If this is what happens I think I'd prefer to have separate inverter and charge regulator and avoid charging batteries from the grid, controlling power source switching in some other way.
TIA
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