Are Solaredge Optimisers Always Worthwhile?

Qyburn

We are planning on putting panels on a sloping roof, orientation 190 DegT (just W of South). There are no obstacles to cause shading. One installer gave a detailed pitch on how the Solaredge optimisers work, but his concrete examples with figures were all where shading occurs at certain times of day, for example from a dormer.

What do people think, would the Solaredge system perform that much better in our scenario?

The comparisons aren't like for like, the Solaredge installer recommends 4kWp panels and 3.6kW inverter. The other option on the table is 16% more expensive but for 6kWp panels (Q-Cells) and 5kW inverter.

Thanks.

Exiled_Tyke

Sounds like you have a sales person trying to sell you something you don't need. If this is the case then all trust is gone and I would run a mile. The only other situation I've come across (because I have it!) is where there a multiple orientation and also roof pitches, which similar to shading causes differing levels of production.   (regular inverters are set up for two strings so you could say have an East facing array and a West facing which can perform separately). 

General rule of thumb is always to go a big as you can afford/accommodate. Do right now option two looks the better. I'd get some other quotes to compare though.  

If you put details of the price and equipment (particularly the inverters) you are being offered then others may have some useful views on quality and value for money. 

Screwdriva

A few things to consider (in addition to shading)

1) SolarEdge inverters won’t work without optimizers but other quality inverter brands do (Fronius, SMA, GivEnergy)

2) Optimizers provide panel level performance across several units of time days/ months/ year), which I find very useful. Indeed, based on this data, we are augmenting our systems Western aspect. 

QCells are an excellent panel brand- I would default to option 2 (assuming the inverter is from one of the brands mentioned above).

Qyburn

Thanks, the two quotes we have so far are (1) £10.4k for 16 Q-Cells panels (6kWp) with 5kW Solis invertor. (2) £8.9k for 12 "JA" panels (4kWp), Solar edge optimisers and Solaredge 3.6kW inverter. Higher prices than I was expecting.

Hopefully more quotes to come, but the surveyor yesterday said they won't install on a metal roof as a matter company policy. No other installers have got back to us yet.

I've just noticed that supplier (1) are also Solaredge installers. But apparently not recommending in our case. Another question for them.

Martyn1981

Both of our systems are Solaredge, and they work extremely well, mitigating the worst of the shading issues.

But, if you don't have shading issues, then the extra cost and complexity probably almost certainly isn't worth it.

If instead (just in that example you give) you can get ~50% more generation for 16% more cost, then that looks like a better investment.

Screwdriva

Same here. We wouldn't change the SolarEdge inverter to any other brand currently on the market. 

That said, I believe both your quotes are abnormally high. Based on the quotes I'm seeing, the max I would expect to pay for a 6.1kW SolarEdge system with 15X Sharp 410W panels is <£7.5K + any costs (long distance charge, bird netting etc.)

Raxiel

If you'd asked me before I got panels if I had shading (and some installers did), I'd have said 'no', but now I actually have them and I'm more aware of such things, I've realised there are times of the day that parts of the roof are shaded.

The tree that I though was too short and too far away does actually cast a bit of a shadow in the morning when the sun is low, and the chimney casts a shadow over the front of the house in the late afternoon. I'd assumed the whole front of the house would be in its own shadow at that point and not something optimisers would help but there's still a decent amount of light falling on the rest of the SE panels at that time.

So it's not always obvious. Proportionally the time these shadows are present on my roof probably isn't significant, but it's satisfying to know I'm getting the best out of it and the package we got with  Solaredge inverter and optimisers was the cheapest quote by far.

Screwdriva

So great to read this! 

Waywardmike

I was offered Solar Edge at install, but it was considerably more expensive than the SMA string inverter we eventually went with.  I understand they're probably on par now as SMA is the more premium end of string inverters and SE has come down in price.

With no significant shading at all, it almost certainly wouldn't have made a difference to my generation.  My installer has converted a couple of string inverter systems to SE since and reported to me 5% increase in generation, so I was probably right to not bother as that wouldn't have covered the extra cost at installation.

What I would love is that panel level monitoring though, I'm a scientist by profession so love data, but then I'm happy I don't have 16 extra points of failure on my roof which can't replaced that easily, so swings and roundabouts.

All this being said, if you have shading or are planning a multi aspect roof system (>2 aspects), you should probably go with Solar Edge.

ispookie666

I would look at users who have had experience with and without panel-level controls.  

I'm probably one of the few on there who have microinverters.  If you have split roofs, it's no brainer.  Shading is a grey area; current evidence indicates it does not matter.  

The more significant benefit of these is panel-level monitoring 

Jonboy1889

Has anyone actually tested the impact of shading one of their panels on a single array to see what impact it has on production? For a recent system? I see different things online, some say you lose up to half to 2/3 of your total output from that array. But then others talk about bipass diodes which means that you just lose the panel with shade 

Be interested to see if anyone has tested the theory on here!