Used panels

[OffGridInTheCity]

When you upgrade the installers dont want to intergrate the old panels so they just chuck new ones up. Replace 190 with 280. The ones I found were in the street for recycling. The owner came out and told me they had earth leakage problems. He said the installer claimed them on insurance and dont try to complain to trina as they were written off. What a load of malarky.

I think that the installers actually can not integrate the old systems with the new.
I think you can only have a 5kw inverter on a single phase, then you can only have 6.6kw of panels on a 5kw inverter.

Inverters like Mpp solar support 9x 4-5kw inverters on single phase.

Average UK home has a 100A 250VAC connection. I'm personal thinking of 2x 5kw eventually

Interesting. My goal is to power my home as well. If it helps you in your planning - here's what I've found.....

I currently have a 7kw array (24panels) in a reasonable (southern Oregon) weather environment which produced usable power from an AIMS 12,000watt (240v@50a) inverter last year as follows:
----------- bad 4 months ----
Nov 420kwh
Dec 212kwh
Jan 322kwh
Feb 330kwh
--- medium 4 months ---
Mar 777kwh
Apr 797kwh
Sep 826kwh
Oct 787kwh
----- best 4 months
May 976kwh
Jun 1144kwh
Jul 1118kwh
Aug 1041kwh

For a yearly total of 8,750kwh. This is perfectly adequate to run everything in my home (including hybrid hot water heater, cooktop, tools, etc...)- but not necessarily all at once. Spring/Summer/Fall there is a pretty good amount of power. Winter is definitely sparse.

As far as max power its interesting as you can plan for serialized use of things to keep the max requirement down but then things happen... for example, yesterday I was running the microwave and then decided to turn on the coffee pot. Meanwhile my wife turned on the cooktop. These 3 simultaneous 'events' + background power (hot water heater, computers, refrigerator, furnace fan, etc) caused a spike up to 7,000-8,000watts momentarily. My point is, that for 'natural home use' (simultaneous events) you might find 5,000watt inverter max a bit low for whole home use. I'm glad I went for 12,000watt inverter as it can easily handle these 8,000watt spikes and we don't have to worry about it.

What I'm missing is heating/cooling...
So I'm in the process of adding another6kw array (21 panels) for whole house heat pump + another 12,000watt AIMS for total capacity of 240v@100a simultaneous power draw capability. This will be enough to powerthe Air Conditioning all summer. Should be enough for several hours of heat in spring/fall. And... maybe hour or 2 / day of heat-pumpheat in winter (I live in mild climate - lows are generally 35-40F most of winter).

At 45panels I'm out of room on my property. Ideally I would like another 20'ish panels... especially for winter... but that would risk making the properly so weird the neighbors might complain etc. I think what I'm trying to say is that solar 'can' power your home - but its not just a matter of 'a couple of panels'. Its taken me a while to fully grasp what's needed.

 

[Oz18650]

When you upgrade the installers dont want to intergrate the old panels so they just chuck new ones up. Replace 190 with 280. The ones I found were in the street for recycling. The owner came out and told me they had earth leakage problems. He said the installer claimed them on insurance and dont try to complain to trina as they were written off. What a load of malarky.

I think that the installers actually can not integrate the old systems with the new.
I think you can only have a 5kw inverter on a single phase, then you can only have 6.6kw of panels on a 5kw inverter.

Inverters like Mpp solar support 9x 4-5kw inverters on single phase.

Average UK home has a 100A 250VAC connection. I'm personal thinking of 2x 5kw eventually

Sorry, I should have been clearer - it should have been

"I think you ARE ONLY ALLOWED a 5kw inverter on a single phase, then you ARE ONLY ALLOWED 6.6kw of panels on a 5kw inverter."

 

[Jon]

Im not sure if its the same all over but in Qld Australia you can install bigger systems than 5kW inverter capacity on single phase with an export limit.
My system is 7.5kW AC, 10kW DC with a 5 kW export limit.

If youre making plenty in the summer and not enough in the winter Id be looking at how many more panels you can put on your existing inverter.

 

[Oz18650]

I just did some reading and this explains things pretty well.
https://www.google.com/amp/s/www.solarquotes.com.au/blog/oversizing-solar-arrays/amp/
The rules for rebates are that you can not have more than 1.33 * the inverter capacity of solar panels and get the rebates, so 6.6kw of panels on a 5kw inverter. As this is a comon package sold, the installers cannot add any old/existing panels or the rebates are lost.
I suspect decommisioning/throwing out working panels was not the intent of the rules, but that is the end result.

 

[Jon]

I agree with your reading of the rules.
I do believe this allows you to add more panels to system if not claiming rebates.

 

[camthecam]

Nice info boys.