Renewables: "talking 'bout my generation"

mrmmhf

Thanks Martyn. I've made the MW correction. Ignorance on my part, assumed kW to mW was the same. Won't be making that mistake again.

LOL - thanks for explaining Os. Was going to be my next question - strictly speaking, there should be an apostrophe in Os.

1961Nick

A pretty decent 4.86 O's yesterday.

mrmmhf

Most of us are geeks....many with OCD as well....so you should fit in fine.

LOL. Love that. It's been a huge learning curve, but forums like this are instrumental in self education.

mrmmhf

In short, too large of an inverter in the UK is not ideal.

Not sure why EON didn't explain this to me. I'll keep monitoring matters.

mrmmhf

34.6 Os yesterday.

mrmmhf

Plus of course PV panel efficiency drops with temperature, around 1% for every 4C.

So confused - I was told by a PV 'expert' that efficiency of panels increases when temperatures drop, so panels become more efficient in colder months, but obviously not as productive because days are shorter.

1961Nick

mrmmhf wrote: »

34.6 Os yesterday.

Should that be 3.46 O's?;)

1961Nick

mrmmhf wrote: »

So confused - I was told by a PV 'expert' that efficiency of panels increases when temperatures drop, so panels become more efficient in colder months, but obviously not as productive because days are shorter.

That's correct & what Mart was saying - 1% reduction in output for every 4C increase in temperature. Black panels suffer the most....and yours are very black!

Martyn1981

1961Nick wrote: »

That's correct & what Mart was saying - 1% reduction in output for every 4C increase in temperature. Black panels suffer the most....and yours are very black!

@mrmmhf, think black car in the sun, the panels get very hot very fast. On a long sunny day, with little to no wind and perhaps 30C air temps, don't expect more than 80% of kWp rating.

BUT I also have a Solaredge HD wave inverter and they are top notch, so anything is possible.


Boring bit - but many years ago, probably 6(ish) one poster was convinced that undersizing an inverter was dangerous, but he was conflating issues with having too many panels on an unsuitable inverter which could lead to too high a voltage, which in turn would damage the inverter.

It got so bad I eventually copied the thread to SMA the manufacturer of the Sunny Boy range he was talking about and mentioning 'exploding inverters'. They suggested litigation might happen if he continued.

The issue there is that a suitable inverter needs to be chosen, and the strings set out correctly to match voltage limits. [Note you and I have single strings thanks to the Solaredge power optimiser technology.]

But from there I started to here about side by side tests of what at the time were seen as the best of the best inverters, SMA SB TL's.

They found that 4kWp of identical PV generated slightly more over a year when connected to a SB3600TL, than the SB4000TL. Plus the smaller model was around £100 cheaper at the time.

But don't worry about my posts, nor my pedantry, be it a 5kW or 6kW inverter, your system looks great, and not only will the difference in generation be small (if there even is one), but you'll never know anyway!

Oh, last thought, [URL="file:///C:/Users/Martyn/Downloads/https___www.solaredge.com_sites_default_files_se-single-phase-HD-wave-inverter-setapp-datasheet.pdf"]the 6kW model[/URL] can cope with up to 9.3kW of DC generation, so ....... and this is where I usually waffle on and ponder away ..... but if in the future you decide to add more PV, then given the Solaredge tech allows you to mix any panels, orientation, pitch etc etc, then you are in a perfect position to do so.

Perhaps some very steep (50-60d) south facing panels to aid winter gen, or perhaps that should be SSW, to compliment your current shallow to average pitch panels.

PV is addictive, car ports, pergola, shed rooves ...... someone stop me for the love of sanity!

mrmmhf

Should that be 3.46 O's?

LOL. No, we had a monster day yesterday: 36.6 Os.