Dillsue

Weve got a 30 evac tube array that pre dates our PV. I beleive that evac tubes give a higher output per m2 compared to PV but obviously PV is more flexible. In terms of reliabilty, ours was installed in 2006 and not had any problems. Changed the heat transfer fluid after 10 years and have topped the pressure up twice from the mains water. If you want in roof panels and flat plate collectors its probably worth doing some research on the performance versus similar area of PV. If you want to see how systems can be connected up, google Resol Deltasol and have a look in the controller manual as theres lots of schematics of differing systems.

Appreciate charging a single battery wont make any difference but if that principle was adopted by lots of battery owners then a gas turbine will ramp up to serve the additional load.

So 100% south facing to cram as much in the battery as you can

Plenty of sagging roofs around so very naive of the mounting system designer not to have included a means of fitting straight rails, if thats the case. Lining up the rails takes time so maybe they rushed things and left out packers or slotted angle brackets?? If your roof was sagging, and that was the cause, youd be able to see the panels/rails running parallel to the roof but in one of the pictures the roof looks to be straight??

Arent the roof hook to rail connections adjustable? This may allow someone to reach in from the side and raise the rail where it dips?? Certainly Renusol rails are straight when they dont have a load so its pretty hard to install them bowed unless its at the joint of 2 sections. Im not one for creating unnecessary work so if it can be lifted from a ladder crack on, otherwise get the installer back as it should be straight to the casual glance.

If youre looking to size a battery then the battery will give you a more useable spread of energy and I would guess youd want your array to generate the max it can by being south facing. As I understand things you only want to split the array to give a longer spread of energy if you dont have a battery or if youve oversized your array.

Picture quality isnt so good on the photos linked to, but is there a transformer at the top of the PCB above the fuse??

Its difficult to see for sure from the picture of the inside but it looks like the boost button is just a PCB mounted pushbutton?? If you can solder you could connect a couple of wires either side of the button, run them to the outside of the enclosure and connect them up to a timer with a volt free contact. Check the voltage on the switch so you know the wiring standards required!

Thats the scheme that everyone started on with a deemed export of 50% of what you generated. Once SEG became an option then you could have metered export if you wanted to give up the 50% deemed option

Use the immersion timer to energise a changeover relay/contactor. Common connected to the immersion stat, NC connected to the Solis and NO connected to L. Solis is normally connected to the immersion and when the timer is active the changeover relay/contactor disconnects the Solis and puts a live feed on the immersion stat.

What Dave Jones and myself are trying to explain is how the FIT payments are made up so you can understand which parts you may loose if you do things wrong. If you look up the revised OFGEM guidance youll be able to see how batteries can be added within the rules

Panel cables are just loose on the MCS installed system we have and on the diy systems weve put in this year. Its possible to do a bit of tidying and cable tying as each panel goes in BUT..... If you want to remove a panel in the centre of a row for repair/replacement and youve tie wrapped all the slack into loops, its gonna be a twat of a job to lift anything but the perimeter panels

That sounds like a whopping export rate but are you sure thats not a combined generation and export rate?? We're on a 2015 FIT scheme and that pays one payment based on generated units from a generation meter and second deemed/assumed export payment based on half the generated units. For the deemed export payment it doesnt matter if we actually export it or use it ourselves, we still get paid it. Have look back through the last few months posts as there was a discussion over some rule changes OFGEM had made that now allowed batteries to be added to an existing system without affecting payments. Maybe search for OFGEM

Before you spend time writing, you might want to explore net metering. If its as I think it could be you should be able to drastically reduce your bills by offsetting any export against import. Search for "net metering" on the forum. Also try asking your electrician to see what he knows and if your export and import are on different phases.

Not sure how the Tigo optimisers work but if you were using solaredge optimisers you dont need to worry about MPPT input voltage as its regulated by the optimisers. All thats required on an SE system is for a minimum number of panels/optimisers to be in daylight, from memory its 8, and thats enough to get the inverter operating. Only time you need to consider panel V/I specs is when matching panels to optimisers. If the Tigo versions work in the same way you probably just need to check minimum system specs to make sure that 6 optimisers is enough to get things working

Did you have another thread about the install of this system?? I thought that some/all 3 phase meters did net metering so if you export on one phase and import on another, the units exported would offset those imported. Net result is youd only pay for any units imported that were more than those exported.

Hopefully thats a typo and its a G99 approval that you already have in place for your 5kw inverter as G98 only covers you up to 3.68kw. Adding AC coupled batteries will be potential extra export on top of what you already have so a G99 application would be needed unfortunately. Its a shame SE dont do smaller/cheaper or scaleable battery options as a DC coupled system seems to have so many advantages.

Can you get a powerwall for self install?? I thought they had to be professionally installed???

British Gas standard variable tariff is price capped at 36p unit and around 50p a day standing charge. Fairly sure those sort of rates will be available from lots of suppliers

Yep. Speak to Octopus and let them know youre plans. If you have the new system MCS installed then I think youll be able to run all your export from both systems through a single meter, but check with Octopus. Dont forget to speak to your DNO first as its all hypothetical until they give the go ahead.

Yes, if youre getting deemed FIT export payments, as all your FIT payments are based only on the generation meter reading. If youve opted for metered FIT export payments(SEG) then youll need to meter your FIT and non FIT export separately.

Q1- you need permission from your DNO to export more than 3.68kw so you should already have permission for your 10kw system. If you want to export more, you need DNO approval of a G99 application. Q2- no problem running 2 or more systems in parallel. We have 2. Q3- its up to you how you configure things and somewhat dependant on what export your DNO will allow, but altering your FIT system is regulated so understand what the rules are before comitting to altering anything

Your DNO approval is for the inverter which will limit export to the grid from either or both PV and DC coupled batteries. If you have AC coupled then the inverter can only limit PV export and your batteries are free to do want they want. SE are quite limited in their DC coupled battery options. I think youve got the recently launched Energybank or the earlier Storedge system using LG batteries. Other than those its AC coupled with an uplift in DNO approved export limit or an export limitation set up

If you go for AC coupled then the battery pack adds to your potential max export and youll need DNO approval for new inverter AND batteries!

Enough said!! I only looked at the first site which is a US site. Youre better sticking to UK focussed sites as rules and terminology differ from other countries. You are correct that its the panels that do the generating and inverters the conversion.