Second system extension extension.

[nowty]

Thsnks Nowty, you texting one handed in the TM3?

Today is not Tesla day !, but I was about to post something on my tesla thread.

[Joeboy]

Thsnks Nowty, you texting one handed in the TM3?

Today is not Tesla day !, but I was about to post something on my tesla thread.

Standing by with keen interest!

[Joeboy]

That's the new string up and running. All good. The output from the 2nd array went straight up and bounced off the 35A limit for this charge controller with the new string operating and the sun fortuitously emerging from cloud. Might have to save up for the next step up in Victron charge controller after I've worked out what we might see from this system running unfettered.. Very happy!

[Stinsy]

That's the new string up and running. All good. The output from the 2nd array went straight up and bounced off the 35A limit for this charge controller with the new string operating and the sun fortuitously emerging from cloud. Might have to save up for the next step up in Victron charge controller after I've worked out what we might see from this system running unfettered.. Very happy!

Great! I was wondering how how you'd know if they are working! I thought you'd need to attach a clamp meter and keep checking it!

I wouldn't bother upgrading the charge controller (unless you see an irresistible deal for a used one on eBay (or wherever)), the point of the extension isn't to increase your max production capacity, it is to increase production in overcast conditions. So that in conditions where your (c.3kWp) array would have been pushing out 1500W now it'll be pushing out 2000W (of it's c. 4kWp).

The point is you (probably) don't need and cannot use/store the extra power on a mild/sunny September day, but you gain a few precious kWh in November when you need every bit. You're taking advantage of the fact that solar panels are cheap, but installation and inverters/charge controllers are expensive.

(On the other hand I might have that charge controller off you at some point in the future, I have plans forming...)

[Joeboy]

That's the new string up and running. All good. The output from the 2nd array went straight up and bounced off the 35A limit for this charge controller with the new string operating and the sun fortuitously emerging from cloud. Might have to save up for the next step up in Victron charge controller after I've worked out what we might see from this system running unfettered.. Very happy!

Great! I was wondering how how you'd know if they are working! I thought you'd need to attach a clamp meter and keep checking it!

I wouldn't bother upgrading the charge controller (unless you see an irresistible deal for a used one on eBay (or wherever)), the point of the extension isn't to increase your max production capacity, it is to increase production in overcast conditions. So that in conditions where your (c.3kWp) array would have been pushing out 1500W now it'll be pushing out 2000W (of it's c. 4kWp).

The point is you (probably) don't need and cannot use/store the extra power on a mild/sunny September day, but you gain a few precious kWh in November when you need every bit. You're taking advantage of the fact that solar panels are cheap, but installation and inverters/charge controllers are expensive.

(On the other hand I might have that charge controller off you at some point in the future, I have plans forming...)

Oh ye will, will ye? I am sure we can come to some arrangement if I upgrade. One careful owner etc....

There is an add on for the charge controller with a jumper cable running to a LCD gauge, Gives Amps, Watts, Panel V, Kw live incoming etc. Plus I know the system so it was literally WOOOSSSHH when it fired up. Pouring rain and thick cloud now of course and the whole PV set up is only putting out about 600W but that's OK.

I had a look at the input wattage from the PV and i was seeing spikes to 1880W falling back to 1820W when the charge control limiter kicked in at 35A.

1820W/35Ax55A=2860kW
4mm cable is good for 55A
The system itself is capable on paper of producing around 3.84kW. If it managed 90% of that on its best 1 off Spring day that would be 3.45kW. That's up about 65A assuming all remain linear which way exceeds the 4mm cable spec. I'd have to limit the controller to 55A in software and make myself be good. There is a 150/60 unit out there but its £470!!!

The second array as was produced 1.67MWh in its first year. Assuming an extra 30% output (pure guess) due to the raised ceiling of 55A with a £470 controller I would see an extra 0.5MWh PA.

OK, fun bit, what's that worth? 15p per unit or 25p per unit or £2 per unit.

Let's do 20p per unit in this brave new world? That's £100 power value PA to us into the EV and HWT. 4.7 year payback less how much I can screw out of Stinsy for this top bit of barely used kit ( I hope you are laughing).

That's not too shabby for back of fag packet...

Thoughts? Also Stinsy, let us know your plans when they solidify and ask away if there is anything to help with?

[nowty]

That's the new string up and running. All good. The output from the 2nd array went straight up and bounced off the 35A limit for this charge controller with the new string operating and the sun fortuitously emerging from cloud. Might have to save up for the next step up in Victron charge controller after I've worked out what we might see from this system running unfettered.. Very happy!

So my second prediction (from the older forum !) may still come true.

[Joeboy]

That's the new string up and running. All good. The output from the 2nd array went straight up and bounced off the 35A limit for this charge controller with the new string operating and the sun fortuitously emerging from cloud. Might have to save up for the next step up in Victron charge controller after I've worked out what we might see from this system running unfettered.. Very happy!

So my second prediction (from the older forum !) may still come true.

It might yet, hard to sit still knowing I could get more out of the system.

[Stinsy]

Thoughts? Also Stinsy, let us know your plans when they solidify and ask away if there is a anything I can help with?

I have a shed (garden office) with a 15° sloped roof facing SSE. Earlier this year the neighbour felled his huge tree that previously overshadowed the shed. Roof is roughly 2485mm x 2400mm.

The challenge is sourcing appropriately sized panels.

Key criteria:
- As low a £/Wp as possible.
- As high a number of W I that can fit on the abovementioned roof.
- A supplier willing to supply a small number of panels for reasonable price inc. delivery.

Favourite for panels at the moment are 2x JA Solar 495W 1,134 x 2,094mm at £165 each (inc. VAT but not delivery).

Years ago 600x1200mm panels where commonplace. With these I'd perfectly fit 8x panels in a 4x2 array. However the W/m² and W/£ of any panels I've found in this size has been unattractive. 4x 600x600mm panels would similarly fit nicely, but I haven't found any attractive panels in this size either.

An array of 4-or-more smaller panels could plug straight into my inverter (it has unused capability for a 2nd array) there are pros/cons of this, but it has a startup voltage of 100V therefore a 2-panel array wouldn't work. Leaving a charge-controller as the next best option, but unless I can source a very reasonably priced used example ( ), this represents a very large proportion of the total project cost.

Input is very much appreciated. No big rush. It is next-year's project...

(In the mean time the storage heater for the garden office (Dimplex Quantum QM050RF HHR) is due to be delivered next week.)

[Joeboy]

Who did u price with?
Don't be scared of a little overhang, it looks ok and does no bad.

My choices for supplier were ITS and laterally trade sparky. I agree on the delivery costs being kept down. I was £75 for a pallet. Tempted to go proper nuts and over order panel volume to keep per down but SWMBO has been incredibly cool so I don't want to take the piss as that's no way to show thanks.

You should have a look for used rail systems and clamps, time is on your side.

You will want to look for a direct pick up if you can?

I genuinely think anyone with batteries should look at this 'The Nowty Option'. Its like having one more benefit to batteries or an Ace up your sleeve for when you need it. Back in the day (pre Nowty) I was a 5kW system, now I'm a 9kW system and I am still adapting to it. Bear in mind, my set up is in no way optimal in location or orientation. Can't imagine what you'll see down there in The Shire.

It will be Epic!

[Joeboy]

Thoughts? Also Stinsy, let us know your plans when they solidify and ask away if there is a anything I can help with?

I have a shed (garden office) with a 15° sloped roof facing SSE. Earlier this year the neighbour felled his huge tree that previously overshadowed the shed. Roof is roughly 2485mm x 2400mm.

The challenge is sourcing appropriately sized panels.

Key criteria:
- As low a £/Wp as possible.
- As high a number of W I that can fit on the abovementioned roof.
- A supplier willing to supply a small number of panels for reasonable price inc. delivery.

Favourite for panels at the moment are 2x JA Solar 495W 1,134 x 2,094mm at £165 each (inc. VAT but not delivery).

Years ago 600x1200mm panels where commonplace. With these I'd perfectly fit 8x panels in a 4x2 array. However the W/m² and W/£ of any panels I've found in this size has been unattractive. 4x 600x600mm panels would similarly fit nicely, but I haven't found any attractive panels in this size either.

An array of 4-or-more smaller panels could plug straight into my inverter (it has unused capability for a 2nd array) there are pros/cons of this, but it has a startup voltage of 100V therefore a 2-panel array wouldn't work. Leaving a charge-controller as the next best option, but unless I can source a very reasonably priced used example ( ), this represents a very large proportion of the total project cost.

Input is very much appreciated. No big rush. It is next-year's project...

(In the mean time the storage heater for the garden office (Dimplex Quantum QM050RF HHR) is due to be delivered next week.)

I just reread, did you actually just try and lowball me via sympathy? I'm an absolute bas**Rd, that doesn't work on me. Points for trying though!