This bit is simple when you distill it down to what it actually does and half the kits come with a dtu as standard. Its just a black box that plugs in and talks radio to the inverters, and repeats this via wifi to a cloud service on the internet. Hence the name, data terminal unit, or dtu.
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Roger you can just buy something like this...
Multiple 6.0Kw Pv Pack - 14X Longi 430W + Sunsynk 5.32Kwh Storage + Fastensol Mounting PVK023
Complete Solar PV pack comprising 14 x LR5-54HTB-430M Longi 430W panels, Sunsynk 5K-SG01LP1 Hybrid inverter with 5.32Kwh battery storage. Fastensol mounting system with mounting rails, Pantile roof hooks, universal mid / end clamps and bird guard. Electrical accessory pack with AC and DC...www.cityplumbing.co.uk
Install yourself do a G99 application yourself, and it all just works. Use manufacturers monitoring and you are done. I have 2400w panels on a shed with a Growatt 2Kw inverter from ebay which has done 1050Kwh so far for a cost of about £500 including buying lots of electrical bits to connect up. Then I have 2Kw of second hand panels I got for £100 with a £60 new old stoick inverter for £60. Mounted using wood on the roof of pent sheds in valley between houses, that's done 450Kwh since I built it last spring/summer. It has basically paid for itself in electric. Gas savings from a Solic 200 cheap as chips immersion diverter means I am probably ahead of costs already.
That seems quite cheap.
I already have a 4.5kw array and invertor. Been on a roof but never used. Seems a shame not to use it.
Is there any real benefit in my case of a G99 application? If i can self consume, whats to be gained?
Thats very generous of you, thank you. Might take you up on that.
Sure, I'm just using hoymiles as a example I know, I chose them originally specifically because it works with the opendtu software and I could keep it all local. I didnt think for a minute about using the chinese cloud and trusting their black box in my network.
Do you have such a thing as a virtual battery tarrif over there? If I bought this here, I can pay more per unit, but when I feed back it goes into storage at EDF, and I use the generated power stored in their battery at night time. If I run only on my stored power, then I pay nothing, but if I use more than my storage, the tarrif is much higher than a normal unit price.
It needs to be legit for the DNO so they know it is there. You could just use a G98 inverter which is a fit and notify whereas G99 you have to apply in advance. If that G98 happens to be an AC coupled storage/hybrid inverter and can hoover up the energy from the rest of the kit hiding behind it (which is what I will eventually be doing) then it doesn't matter to the DNO.
If you use a diverter like my solic you could send the power to your house hot water tank via an immersion or stick some electric underfloor heating in useful places so you aren't exporting it. Run aircon in the summer or heat a big lump of concrete in the workshop as a thermal store for the winter. The grid is just there to take any excess you can't use.
If you use a diverter like my solic you could send the power to your house hot water tank via an immersion or stick some electric underfloor heating in useful places so you aren't exporting it. Run aircon in the summer or heat a big lump of concrete in the workshop as a thermal store for the winter. The grid is just there to take any excess you can't use.
I was keen to diy and use what i already own, but accept that i might be a bit too dumb to actually achieve it! And so should just pony up and buy a complete system.
I like that idea, but I don't think such a thing exists here.
to be honest, iver never really fully understood the G98/99 thing. If my system cannot feed the grid, do i still need to? Seems hard to find a clear cut answer to that?
Your workshop looks like a great solar experiment waiting to happen.
I would probably buy a 3.6kw Sunsynk hybrid - kit from City plumbing would be easiest, you can use their solar PV kit builder to assemble one with lots of panels for the inverter size. Then it's just a G98 for the DNO then set up the stuff you already have hiding behind it. If you don't want to export you don't need MCS at all. In terms of battery, you have lots of space so maybe find some forklift batteries???
And if you have a field for a ground mount you are laughing.
Do you have 3 phase?
If it's connected to the grid it can feed it, so best to do it properly. Mind you I have accidentally not done that for my current setup!
I have a battery forklift. Its rarely used.
Yes i have a field.
No i dont have 3 phase. Theres a 3 phase pole 50ft from the barn in my field, but national grid wanted £20k to connect me with me doing all the work. You wont be surprised to know i declined their generous offer!
So you could actually use your existing forklift batteries as the storage if you wanted, which is an interesting option.
If you are building a ground mount you can just use timber/unistrut/whatever rather than buying that kit with the rails etc included.
CPS have 405w Longi panels for £49.82 inc VAT which is the cheapest option. Get a load of them and a hybrid inverter and you are up and running.
If you are building a ground mount you can just use timber/unistrut/whatever rather than buying that kit with the rails etc included.
CPS have 405w Longi panels for £49.82 inc VAT which is the cheapest option. Get a load of them and a hybrid inverter and you are up and running.
Its not a question of being dumb, its a question of different backgrounds. I've plied my trade tinkering and hacking about with linux and embedded devices for 25+ years now so it all seems simple blocks that bolt together to do the thing to me and it means I understand whats going on inside the boxes easier.
DrJim has your back better knowing the local regs and what is easier for a keen layperson and you'll still get to diy it. But I wouldnt throw away what you have, as he suggests, get the official kit working, then sneak in the extra capacity using what you have behind it.
I ummed and ahhd about trying to calculate the cost benefit for years, and we had it down as a 10 year yield to pay for itself, but the numbers in reality are much better because we didnt just pay for some installer to rock up and fit their own kit blindly. But there will always be days when it really really sucks. Today I've been spraying a car most of the day, so booth heating, and two compressors all day, and its been a particulary crappy miserable rainy winter day.
Just been checking the forklift battery spec. Looks to be a 22kWh pack. But lead acid meand usuable is circa a third of that. Useful amount though.
Do you not think i can use my existing panels and invertor?
It came with two, one in this pic. Cant get to the other at the moment.
I dont know more than that
Is there a data plate on the side of it somewhere to give us a clue what it can do?
Although my immediate thought is to buy a new inverter, put the panels on a ground mount in two strings wired through those DC switches and connect it to your workshop. If you have 4ish Kw of panels you are looking at maybe 4-500 quid for a shiny new inverter with an instruction manual. Sell the secondhand ones on ebay.
Although my immediate thought is to buy a new inverter, put the panels on a ground mount in two strings wired through those DC switches and connect it to your workshop. If you have 4ish Kw of panels you are looking at maybe 4-500 quid for a shiny new inverter with an instruction manual. Sell the secondhand ones on ebay.
Ill dig the invertors out tommorow and take some pics. They are curently in a pallet on the racking with all manner of car parts in the way!
