Having grown tired of regularly replacing microinverters at significant cost I have bitten the proverbial bullet and had a brand new solar PV system installed. No more technology up on the roof for me, just a simple single inverter in the garage and new 440W panels!

There was nothing wrong with the existing panels but it did not make economic sense (particularly labour cost) to remove all the existing panels/microinverters, then remount the old panels and rewire with DC cabling as new panels are so much cheaper now. So I now have a brand new system with new warranties which at my age should ā€œsee me outā€ as they say, hopefully until the end of the F.I.T. payments in 2031 at least!

Hence I have twenty one fully functioning 185W panels for sale. They were installed by an MCS registered company but I have no idea of their current value. Any ideas as to what I should be looking for?

Thanks.
Jeff

Posted By: philedgeHave a look on ebay but I'd guess Ā£10-Ā£20 a piece.

If you've changed the total capacity of the panels/system don't forget to notify your FIT payer

Thank you. I've had a look on eBay and I can't find used panels like mine i.e. 185W, most seem to be of higher output so difficult to compare. However there are some around the 200W mark and they are of the order of Ā£30 to Ā£35. Maybe I should go for Ā£20 ono.

Yes, I submitted an actual specification and drawings of the proposed layout from the solar PV installer to the FIT provider before I signed the contract with the former. I didn't want to take any chances and got written approval from the FIT provider company. The output of the old system was 3885W (21 x 185W) and the new one is 3600 (8 x 450W), so slightly less.

The used panel market is flooded with panels from solar farm upgrades

Unfortunately, the used prices are about Ā£20-45 per panel, irrespective of the quality of the panels.

Used Tier-1 Sanyo/Panasonic panels can be had for the same price as a nasty no-name Tier 3. You might get more selling it as a complete system with the micro inverters and roof rails.

I feel your pain regarding the microinverters - we stopped installing them except on single-storey or flat roofs with easy access, or ground mount systems.

Even the good ones had very high failure rates, and the guarantee only covers the inverter, not the scaffolding and labour to replace.

Do you know the make and models of your panels and inverters?

Be careful being drawn in by long manufacturer warranties for anything on the roof. The cost of labour and access almost always largely exceeds the cost of a panel/optimiser/micro inverter and the manufacturers warranty is unlikely to cover the labour/access.

Re Solaredge optimisers, the ones we have on our 2015 FIT system are integrated into the back of the panel and I guess they get alot hotter than the free standing ones that sit beneath the panels. That may account for higher failure rates. We've had 3/16 panel integrated ones fail and 1/24 non integrated ones fail

Re householders liability, I'm not sure householders are necessarily liable if a workman has an accident on your property. Most workmen you engage are engaged on the basis that they know more about their work than the householder- roofer, electrician, plumber etc so they are considered able to assess any risks and mitigate them. If mitigation fails then that's down to the workman. If the workman is employed then it's their employer who's responsible for their welfare.

AFAIK a householder only takes on liability if they knowingly or negligently didn't share their knowledge of a hidden hazard with a workman ie if I knew there were uninsulated cables under floor boards and a workman touched them and got electrocuted then there'd be a case for me to answer. The risk of falling off a roof while changing a panel is down to the solar installer to mitigate with a scaffold or rope and harness??

Posted By: philedgeBe careful being drawn in by long manufacturer warranties for anything on the roof. The cost of labour and access almost always largely exceeds the cost of a panel/optimiser/micro inverter and the manufacturers warranty is unlikely to cover the labour/access.

Agree!!!

"AFAIK a householder only takes on liability if they knowingly or negligently didn't share their knowledge of a hidden hazard with a workman ie if I knew there were uninsulated cables under floor boards and a workman touched them and got electrocuted then there'd be a case for me to answer. The risk of falling off a roof while changing a panel is down to the solar installer to mitigate with a scaffold or rope and harness??"



Work at Height Regulations 2005 (as amended):

places duties on employers, the self-employed, and any person that controls the work of others (for example facilities managers or building owners who may contract others to work at height).

As part of the Regulations, duty holders must ensure:

all work at height is properly planned and organised;
those involved in work at height are competent;
the risks from work at height are assessed and appropriate work equipment is selected and used;
the risks from fragile surfaces are properly controlled; and
equipment for work at height is properly inspected and maintained.


There is a simple hierarchy for managing and selecting equipment for work at height. Duty holders must:

avoid work at height where they can;
use work equipment or other measures to prevent falls where they cannot avoid working at height; and
where they cannot eliminate the risk of a fall, use work equipment or other measures to minimise the distance and consequences of a fall should one occur.


As a homowner, it is your duty to ensure a risk assessment has been conducted and that any works are conducted in a safe manner. Any risk assessment should work on the 'hierachies of risk' basis - to cut a long story short, you cannot justify working off a ladder alone.

In addition, under common law, the homeowner is ultimately liable for any injury on their property (even if the person injured was trespassing at the time), as well as for any affected member of the public on adjacent property.

When solar panels are dropped, it is rare for them to head straight down - they tend to glide at an angle and sometimes for a considerable distance.

I was nearly killed by a panel falling from a roof - even though I knew it was heading towards me - it wen't edge on and I lost sight of it until it grazed my neck! There were two children standing next to me watching the work... and we were on the public pavement next to the house.

So even if it is not you or the 'solar engineer' who is injured, it could easily be your elderly neighbour in her back garden, or the postman delivering your mail.

Posted By: philedgeI'm pretty sure the law wouldnt put the onus on an unqualified homeowner to control a high risk activity. In a domestic environment, those in control of the work would be the business engaged to carry out the work whether they are self employed or a company.

I agree with this.
IMO If you employ someone to carry out works then that person has the responsibility for the work and the way it is carried out.

Over here e.g. if you employ a roofer to replace your roof, if he does it without a plan (drawing) then he has the liability, if it is done with a plan and he follows the plan then the liability is with the producer of the plan. But the contractor always has the liability for safe working.

For DIY work, when in the UK (and here BTW) my household insurance had a 3rd party liability clause which would cover e.g. things falling of a roof and hitting the postman. If the DIYer can show safe working practices (including signs etc.) I would expect this cover to apply to DIY work. Of course I would expect the insurance co. to try wriggle out of any liability as per their normal approach to claims.

Back to the use of scaffold to replace a PV panel - this is all part of the total risk aversion in the UK. They darenā€™t not use it.

Over here when my PV was put up (7M to the gutter line and a 35 deg roof) the workers used a ladder with lift attachment the get the panels up having first gone up the ladder to walk around the roof sliding the tiles up as needed to get a foothold on the tile battens.

Posted By: sgt_wouldsNot such a problem in Europe, and especially Hungary, as the foreign battens seem to be on average twice the size of UK spec.

The standard tile batten here is 30mm x 50mm, but our rafters are typically have 900mm centres and we use 100 x 150 rafters

Posted By: sgt_wouldsHaving said that, most of the builders I know in Hungary like to have a tot of Palinka before starting work, so they probably would bounce just if they fell off the roof... :-)

One of the best roofers I used drank 1.5 ltr of wine through his working day. Unfortunately he fell off a roof on a 4 story building in Budapest. End one good roofer. (luckily nothing to do with my projects)

It's not necessarily the case that scaffold is required for all roof work. The HSE specifically say that ladders may be appropriate dependant on the task and duration.

No reason not to access a roof on a ladder to measure a panel or check type or condition of roof covering. If you want to change an optimiser or clean an array use a rope and harness once on the roof. Use an alloy tower for a panel change. For me an expensive full custom scaffold is only appropriate for extensive repairs or installation works where the work is going on for hours/days and involves several people.

It's a tradesmans welfare/livelihood at stake with any accident so it's their call if they want scaffold for a minor job but they need to be mindful of going OTT with H+S and over time the cost of doing a job becomes prohibitive so it doesn't get done and they loose work

Posted By: Jeff B 2025The company that fitted our new solar PV system used what I can only describe as a kind of "hybrid scaffolding" - part tower, part interlocking horizontal bars.

Any chance you have a photo?

Posted By: philedgeI don't think the average homeowner will have the knowledge and experience to control working at height so the regs wouldn't apply to them?

One thing that would apply is the Construction (Design and Management) Regulations; they apply to all building and construction work. In particular the designer has a duty to eliminate or reduce risks to those who will have to maintain the works. For a PV installation, for example, that might include providing suitable anchoring points for harnesses, if that's the expected means of access for maintenance.

Posted By: djh

Posted By: Jeff B 2025The company that fitted our new solar PV system used what I can only describe as a kind of "hybrid scaffolding" - part tower, part interlocking horizontal bars.

Any chance you have a photo?

No, sorry.

Appended the components of Kwickstage scaffolding. I bought 2 runs of the stuff and load of extras when doing our build. As It was me that was using it and not trades I did not need a certificated install. My brickie was and ex employee of a construction company and had previously held a scaffolding ticket and he was happy to use it.
When I needed to get the rendering done I had to take it down and get "normal" tubular scaffolding errected by a scaffold company as the rendering contractor would not otherwise be insured.

Posted By: fostertom

Posted By: Jeff B 2025In my experience (unless shading is an issue, which it isn't in my case, but I just liked the idea of microinverters so I could monitor each panel individually) then keep it simple with a single inverter housed in a nice dry indoor location!

Good to know. Why can't microinverters be housed 'nice and dry' in the loft, even if remote from its panel?

I also asked this question at the time. All I can remember was that there was an issue with the length of cables that would be required if all the cables were to have a single point of entry through the roof. It made no sense to me. However there is an interesting discussion on this subject here:

https://forums.mikeholt.com/threads/micro-inverters-in-the-attic.146062/

I must admit I hadn't considered the temperature aspect. I do remember being concerned about the possibility of fire in the attic as this could start entirely unnoticed until it really took hold!