Second system extension extension.

[Joeboy]

TBH Stan, I'm a huge fan of relatively small amounts of power over a decent timeline on marginal days so even a 600W output is significant in my daily routine during the back months. I look forward to hearing what you get for output once it's all up and running, good time to do it too. Looks great on the field!

[Stinsy]

In the end I modified the frame design to give more clearance for grass growth, with all the angles staying the same.





When coupled in series and open circuit, the 2 panels show 89V DC roughly in bright sunshine. One panel on its own gave around 41V in very poor light, too poor for generation . I am going to buy a Growatt TL X grid-tied inverter. My dilemma is that the 0.75kW model has a start voltage of 50V DC and the 1.0kW model has a start voltage of 80V.
I would prefer the 1.0kW model to maximise output from 990Wp of panels but it may be cutting a fine line on start-up voltage. Neither model outputs above its specified wattage. In reality, having the 0.75kW model may mean minimal loss of output at this time of year when it is most valuable. I already have 2.5kWp on Fits.
To add to the matter, Bimble sell a kit with 2 of these panels and the 0.75kWp model. I think I know the logical answer.
PS, the post in the foreground will go.

I'm evangelical about over-sized arrays! Sure you miss out on a few W in bright sunshine when you struggle to use all the power, but it is the bright-overcast days when you really need the extra power.

[nowty]

I'm evangelical about over-sized arrays! Sure you miss out on a few W in bright sunshine when you struggle to use all the power, but it is the bright-overcast days when you really need the extra power.

Absolutely, which is why I have some on my NE facing roof and on my NE facing shed although the shed roof is only about an 8 degree angle. It outperforms even south facing ones (at the usual 35 degree roof angle) in overcast conditions.

And also one on my car port facade at about 80 degrees, not much in summer but Autumn to Spring the low sun sun makes it outperform at the time of year that you need it.

[Joeboy]

It also looks as if and due to going ground mount that you will have ability to expand further if need be...

We often speak of the benefit of the larger array in poor conditions to keep it all ticking over at low wattage to avoid grid. I have also found that as the overall array has grown we are now catching meaningful volumes of energy in the on/off fast cloud scudding days. That larger 'net' is most certainly of benefit for the minutes at a time of full sun. Very well reflected in the SOC on the stack, even as recently as 14 months ago I'd likely be grid grabbing by later in evening or certainly by early hours. We are now rolling right through to the next morning albeit at about 18% SOC for example but a win nonetheless..Also, that next morning we have enough in the tank to couple with the meager early inflow of PV to fire up the washing machine or similar. I know this must be incredibly dull to read yet it's these very shoulder months that I've been playing for. April to most of Sept are a shoe in so not even in the game! Would like to be doing it on our own thru to mid Nov.then pick up again Mid March. That seems achievable for our location and what we have.

[Stan]

I’ve no wish to go bigger on this particular array Joeboy because it is my ‘plug-in’ system. Other developments may well come in the future.

I was wrong when I wrote earlier that the Growatt TL-X 1kW inverter has a start-up voltage of 80V DC although I have read that somewhere. In fact, all of their smaller TL-X inverters have a 50V start-up as I’ve seen on their specifications. So I’ve been worrying about nothing and I have ordered the 1kW model this afternoon.

[Joeboy]

I’ve no wish to go bigger on this particular array Joeboy because it is my ‘plug-in’ system. Other developments may well come in the future.

I was wrong when I wrote earlier that the Growatt TL-X 1kW inverter has a start-up voltage of 80V DC although I have read that somewhere. In fact, all of their smaller TL-X inverters have a 50V start-up as I’ve seen on their specifications. So I’ve been worrying about nothing and I have ordered the 1kW model this afternoon.

Good to know Stan, one of the beauties of PV is that very extendability without cost to existing even across longer time lines...

[Stan]

Opposite for me. A week of good solid 10kWh days has made way for a gloomier weather. I'll probably do well to get 2kWh today. These are the days where every kWp of generation capacity helps (I'm still confident of getting through without using any "peak" electricity).

Now moving into the part of the year I find to be interesting. Oct to Feb will be the months i'll truly see if the extra work put in this year has had a decent impact. It's the gas figure I am watching as the Electric figure is now very skewed with the EV. A good 'problem' to have! Are your plans for next Spring for your own solar extension Stinsy?

Yes! When I built the garden office 6 years ago I cheaped out and went for bargain basement felt on the roof. So as soon as we have a dry spell in March or whenever I'll redo the felt (with 15 or 25 year guaranteed decent stuff) and throw a few panels up there. We'll have the EV by then so will be able to make the most of the electric even in summer. I hadn't realised how much fuel the XC90 PHEV saved us! I used to put £20 a month in the Diesel Audi and £20 every other month in the PHEV now I'm using more than £60 a month with just the Audi!

I've ordered a storage heater for the office (coming Wed next week) and a couple of oil-filled radiators. I'm sensing that gas might be more expensive than resistive electric heating on the cheap rate this winter.

I’m not a fan of felt Stinsey, whatever quality. Have you considered covering the old felt with box-section, corrugated, plastic-coated steel sheets and fixing the PV to that? I’ve used it on 4 outbuildings with no regrets. It has a long life.

Standard fixing




Lateral thinking fixing (this is a smashed panel, free from the nearby solar farm).

[Stan]

Switching on was utterly painless.
I’ve just seen 860W At 14.40.

[Joeboy]

Switching on was utterly painless.
I’ve just seen 860W At 14.40.

Excellent Stan! We saw a huge leap for monthly take on 2nd array install and the Shell extension kind of rewound the season by about 6 weeks on fire up. Great to read of your win! 860W is off the combined array or off the new install only?

[Stan]

Thanks Joeboy. That 860W is off the new system, in addition to whatever my 2.5kWp system was producing. I’m over the moon with that.
I was apprehensive about start-up issues but it just started working once AC isolator then DC isolator were turned on.