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Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 04:04am 11 May 2018
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I have noticed with panels I have setup temporarily close to the ground that they make significantly less power than those that are up higher and can see a lot more sky. Even with the sun shining directly on 2 lots of identical panels. This probably would not matter if you have an open paddock unlike where I am and lots of trees around. There are only 10 types of people in the world: those who understand binary, and those who don't.
Solar Mike Guru Joined: 08/02/2015 Location: New ZealandPosts: 1138
Posted: 04:17am 11 May 2018
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Interesting, possibly closer to the ground means less air movement so they run hotter and thus slightly less efficient. I know when occasionally cleaning my panels with the hose in the late afternoon they increase their output, until they warm up again.
George65 Guru Joined: 18/09/2017 Location: AustraliaPosts: 308
Posted: 04:37am 11 May 2018
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I used the shed roof first and when I literally covered that, North and south sides, started on the west roof of the house. The 5 Kw will go on the north side but I have been planning it though at length because 35o tine roofs are not easy to work on. I have thought very long and hard about ground mount but it would just detract way too much from the look of the yard. Would be OK if I have more land but being only an acre, it's fairly well laid out.
I have been putting the panels flat on the tin roof. I just remove a roof screw, give a good squirt of silicone in and around the hole and then replace the roof screw with the panel clamp and tighten it down again. The house is getting on for 20 yo so the seals on the screws can be a bit brittle when disturbed. I'm satisfied the sealing is better when I'm finished than when I started. :0)
Surprisingly, local council has NOTHING to do with panels here. Asked Mrs about that who looks after these sorts of things for a local council and she thought the question was a bit amusing. As I told her, they stick their nose in enough other things trying to get a handout of a residents cash.
My argument exactly. While here and in other parts they don't own the power directly, all big biz in in cahoots with gubbermint and there is always taxes etc the gubbermint get so it's a conflict of interest when they start talking about being green motivated when so much of that takes Revenue out their coffers.
Here they do what they have to in order to satisfy the green movement but that's about it. They are whittling away the subsidies as quick as they can and the power co's are also doing the least they can to make PV worthwhile with uneconomical feed in tarrifs.
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 06:51am 11 May 2018
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No this is a large drop in output due to less sky that was visible from the panels due to trees etc.There are only 10 types of people in the world: those who understand binary, and those who don't.
Mulver Senior Member Joined: 27/02/2017 Location: AustraliaPosts: 160
Posted: 11:04am 12 May 2018
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Unfortunately the Solar HWS has seen its day the HWS panels are all rusted out and have been bypassed for 5 years or so and the HWS runs on offpeak boost instead. The tank is probably 15 years old and the sacrificial anode will not undo. The cost of PV and a simple HWS I just cant argue with! Easy to work on on the ground and cheap to fix...
My plan is to run ALL my strings to a stripped Aerosharp box through the Mosfets as you have figured out, then from that to each respective GTI. This way i can control all the power coming in and decide what to do with it, while I'm solely on grid ATM I need to ensure I'm not pushing more that i should into the grid. Then after this ill concentrate on the diverting loads with the excess power like HWS and heating my home, then ill work on building the OGI.
George, Im curious what is the layout of all your strings and how many GTI's you got running ATM?
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 12:12pm 12 May 2018
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There may be others that do it but I have Eversolar and Zeversolar inverters, same company but changed ownership. In conjunction with a Eastron energy meter and the Zeversolar communications device. You can then programme a limit on how much power is exported. So if you have power going to the HWS and your AC and 5KW left over to export then your HWS thermostat clicks off it will keep the export to the set limit by reducing the output of the inverter. You can have quite a few inverters connected together, it just tells all the inverters to back off as required.There are only 10 types of people in the world: those who understand binary, and those who don't.
George65 Guru Joined: 18/09/2017 Location: AustraliaPosts: 308
Posted: 01:11pm 12 May 2018
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ATM I have 6.5 Kw of 250's on the north side of the shed. These are running through a 5kw Delta? Inverter. there are 2 strings on this setup. On the south side I have 3.5 Kw of 190 and 180w Panels running through a 4.8? Kw Bosch inverter. This is also 2 strings and paralleled at a junction on the roof. Very little volt/ amp difference between the 2 strings. The shed roof is only 5 and 13o pitch so the south of the shed works out better overall than the west side of the house at 35o
On the west side of the verandah I have 2KW of 180s going through a 3.6Kw Aurora inverter. Just a test setup atm. One string only. These are the leftover panels from the 180's on the shed. I'm not happy with the output of these and am thinking to put up some of the 250's I have for the north of the house to see how they do in the same location. It's clear and gets good sun so I'm sus on the 180 panels output.
On the west side of the house roof I have 4Kw of 240's running through another 3.6 Aurora. These are 2 even strings. Lying flat on a bit of garden I want to burn the weeds out of, ( which panels do effectively on grass) I have 2KW of 250's through what I think is an aerosharp 2kw inverter. It's pretty weathered and I haven't paid much attention to it. Makes about 4.5 Kw day atm so all good to get something out of them and cook the bulbs of the weeds as well.
I have 5Kw of 250's to go on the north side of the house which I'll probably use the Bosch inverter for and swap an aurora to the shed. That may be bit of a squeeze though, house is only 10M wide and of course the roof pitches up so looses square dimension. Being 35o and tin, I'm having a good hard think about the best way to get the things up there. No verandah to work from or catch a person in a slide. Mate has a proper harness so I'll definitely be using that.
I still have well over 8mx5M of west facing roof on the south half of the house I haven't touched yet plus I could probably get another 3kw at least on the other half of the west roof. I only have one string on that over the verandah because I could stand on the lower roof and slide them up. Loads of room above them for another string of 8 and If I really wanted, I could go another lot above those but the TV antenna would shade them a bit.
Yes, Loads of roof, advantage of having a 25M wide house, with shed and Verandahs. Might be another 10x9 shed behind the other one yet... thinking about it. We are also considering changing the verandah and instead of having it running North south as it is now, it will go 7m out east west which will give more north roof. If we do that, I'm thinking of having it skewed so it is all North facing with a vertical south face. Would work well with the rest of the house roof anyway. That would be good for another 3 rows of 7 panels and I could have everything north facing then and take the west and south panels off.
East side isn't touched yet either and probably won't be. I have a MASSIVE gum in the front yard that would render the east side useless with shading it's at least 50M tall and 30M wide. A some point the tree will probably have to come down though which I expect to be about a $10K bill. I will be having the truck cut up to make dining tables from. It's at least 6x5ft wide up to about 6ft off the ground.
I think I'll have more than enough panels in place without worrying about the east side though.
One thing I was thinking though just in theroy..... My neighbours shed is very close to mine. He has at least 4 runs of 10M that panels could be put on which he is with my suggestion looking to do as he is well out of north facing house but plenty on the shed.
I was thinking if someone was roof challenged and happy for some DIY, a person could do a deal and " rent" a neighbours roof space. You could put up panels and inverters and give them a share of the generation for letting you use their roof. I n this case, say do them one run of panels and an inverter which went back to my neighbors power and have the other 3 runs going back to Mine. Only a matter of digging a trench between the properties to run the cable and the sheds are a lot closer together than they are to our houses anyway.
Could be something some friendly neighbors would be happy to do. I know mine would be stoked if I offered him such a deal! Not like he's making money or saving it with the bare arsed roof just sitting there now!
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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Then after this ill concentrate on the diverting loads with the excess power like HWS and heating my home, then ill work on building the OGI.