Bitte_Kein_Lexus wrote: ↑Sun Jan 03, 2021 10:20 am Cool! I'm probably mistaken then. Would be the very Cambodian thing to do (allow it, but conveniently not compensate people who actively contribute energy to the grid, despite energy shortages). I know NGR, they seem like a good company and quite professional, though I've never dealt with them personally (I've met some of their staff).

4kw is pretty big, but it obviously gives great energy savings. I've heard it still takes 10+ years to recoup costs )at which point new batteries are needed), but I like the idea of energy semi-independemce, plus coats are always going down.

AndyKK wrote:

khmerhamster wrote: ↑Sat Jan 02, 2021 10:13 pm

AndyKK wrote: ↑Sat Jan 02, 2021 9:33 pm Quote - there's no system in Cambodia for EDC to pay you for power you feed in. "Off grid system" can still be connected to the grid, but doesn't feed in to grid.
I remember sometime back when a Chinese factory owner asking if he could go solar, mainly because of the power cuts, then obviously it's tool's down stop work. He I seem to remember asking HE to intervene, HE replied it not really being his business to do so, but the outcome was the owner would set up the system, cost $1million, but the electric company would loss the money he would have paid for the electric per month. I think the outcome was the owner could go on solar at his own expense but still pay half of what his monthly bill would have been to EDC.

I don’t understand this at all. Why would they need to get permission? My office uses 75% of its power sourced from solar. I didn’t tell EDC, I just started using less mains power once installed.

Hopefully if the CEOcambodianNEWS sees this they may find the news story I am taking about. Yes there's no way anyone can put back into the grid and get paid for the electric.
But what I was saying about the factory, was the owner was making a point with the power cuts, the factory was not working efficiently.
So he was going to install solar, but the electric company would then be on a loss, so they wanted compansation for part loss.

Bitte_Kein_Lexus wrote:

khmerhamster wrote: ↑Sun Jan 03, 2021 11:42 am sized office building. I think back when buying it i worked out a c. 6.5 year payback for us. But i don't have any batteries.
But we would run the aircon more these days than previous so your usage habits do change a little.

No batteries? So just panels with an inverter connected to power line? I suppose for an office it makes total sense as peak usage will be during the day. Any ACs in use during the day (if so, how many?) to get your cost reduction of 75%?

timmydownawell wrote: ↑Sun Jan 03, 2021 11:18 am I think if I went 100% solar, a 2 to 2.4kW system would be fine. I ran my numbers through this website: https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#PVP

It said I'd run out of battery juice on 6% of days or something so I upped the panels to 3.2kW which is overkill, and 9.6kWh of LiFePO4 batteries, with the panels producing twice as much power as I'd need in the sunniest months (i.e. now/winter, when I hardly need the AC), although it'd drop me to just three days a year with flat batteries. The problem with these calculators is they assume your monthly average use is the same throughout the year which is ofc not true.

Anyway 3.2kW is ridiculous. I added the Phnom Penh rainfall to show how it relates to the reduced output during the rainy season.

Energy Output is me using 6.7kWh/day
Energy Lost is power produced but unused



Even at this level of overengineering I estimate the system would cost around $3500, maybe a little more.

Do you ever use AC? I'm guessing not? Cool website.