Solar Panels UK - is it worth it?

[Avendit]

We are looking at having 5.92kWh system installed which will use 16 x JA Solar Mono 370W panels, 5.0 KW Hybrid Inverter and a 9.5 Givenergy battery.

I've settled on the battery and inverter but was interested in your thoughts on the panels which have a 19.8% efficiency - a little lower than the panels offered by another installer who suggested Trina Vertex 395W panels with a 20.5% efficiency.

With PV the number are pretty much the numbers. Add them up, divide by coat and decide if the extra power is worth the extra cost. Over 16 panels that an extra 400w max output. Is that an important 400w? (Probably 2-2.5kwh per really good day??) Only you can say.

I used to be playing the waiting game saying I should wait for the next breakthrough etc, but even one of the sellers of the next gen panels said 'get whatever you can as soon as you can, don't wait'. So I did, 22 panel x 385w system ordered and queued for fitting.

Now, if some fundamental tech change country mes along that I can get better output in winter or something, that's different. But otherwise it's all scalar and doesn't really make huge differences unless you are at utility scale installation!

 

[YYY2022]

We are looking at having 5.92kWh system installed which will use 16 x JA Solar Mono 370W panels, 5.0 KW Hybrid Inverter and a 9.5 Givenergy battery.

I've settled on the battery and inverter but was interested in your thoughts on the panels which have a 19.8% efficiency - a little lower than the panels offered by another installer who suggested Trina Vertex 395W panels with a 20.5% efficiency.

We are looking at having 5.92kWh system installed which will use 16 x JA Solar Mono 370W panels, 5.0 KW Hybrid Inverter and a 9.5 Givenergy battery.

I've settled on the battery and inverter but was interested in your thoughts on the panels which have a 19.8% efficiency - a little lower than the panels offered by another installer who suggested Trina Vertex 395W panels with a 20.5% efficiency.

Do you mind sharing your ballpark quote for the panels installation please? I understand if you rather not. Thanks.

 

[nickLeeds]

Hi, I have some solar quotes including a Powerwall. I understand the lead time on a Powerwall is likely 9months. Has anyone added another battery first then added the powerwall? So maybe get a small Givenergy one in addition to the powerwall. It’s a 5.6kw array with solar edge inverters, as I work from home I want to protect from power cuts(using the PW2). Thanks

 

[WannabeOwner]

maybe get a small Givenergy one

Are they on significantly shorter lead time? (I don't know the answer to that)

 

[Yachtsman]

Hi, I have some solar quotes including a Powerwall. I understand the lead time on a Powerwall is likely 9months. Has anyone added another battery first then added the powerwall? So maybe get a small Givenergy one in addition to the powerwall. It’s a 5.6kw array with solar edge inverters, as I work from home I want to protect from power cuts(using the PW2). Thanks

Why not look at a SolarEdge inverter & batterybank, this combination can also give you protection from power cuts, but I’m not sure if delivery times are any better.

 

[Fursty Ferret]

I've got my order in for the SolarEdge stuff, but from an electrical point of view it's going in with wiring in place for a battery, but that will have to come later.

 

[nickLeeds]

Why not look at a SolarEdge inverter & batterybank, this combination can also give you protection from power cuts, but I’m not sure if delivery times are any better.

Thanks I’ve been looking at that but can’t see that it provides backup in the uk? Is StorEdge now part of the HD wave inverters or do you not even need it for Energy bank?

 

[Yachtsman]

Thanks I’ve been looking at that but can’t see that it provides backup in the uk? Is StorEdge now part of the HD wave inverters or do you not even need it for Energy bank?

Hi Nick,
I’ve gone down the SolarEdge route because the PW2 was not available until Sept/oct this year (I ordered in January). I’m not having the power cut protection since I don’t think it’s necessary but it can be added later.
I’ve ordered a 4.8kWp panels (not SolarEdge) with optimisers, a 5kW HD wave inverter/EV charger & 10.3kWh batterybank, 5kW charge/discharge. Installation early May.

 

[Mrklaw]

Hi, I have some solar quotes including a Powerwall. I understand the lead time on a Powerwall is likely 9months. Has anyone added another battery first then added the powerwall? So maybe get a small Givenergy one in addition to the powerwall. It’s a 5.6kw array with solar edge inverters, as I work from home I want to protect from power cuts(using the PW2). Thanks

Givenergy has a smaller backed up supply you could tap into. Not a fully off grid but if you don’t have lots of power cuts you may be able to manage with eg router/WiFi/computer sockets on a backed up supply as a big UPS?

 

[Andy718]

With PV the number are pretty much the numbers. Add them up, divide by coat and decide if the extra power is worth the extra cost. Over 16 panels that an extra 400w max output. Is that an important 400w? (Probably 2-2.5kwh per really good day??) Only you can say.

I used to be playing the waiting game saying I should wait for the next breakthrough etc, but even one of the sellers of the next gen panels said 'get whatever you can as soon as you can, don't wait'. So I did, 22 panel x 385w system ordered and queued for fitting.

Now, if some fundamental tech change country mes along that I can get better output in winter or something, that's different. But otherwise it's all scalar and doesn't really make huge differences unless you are at utility scale installation!

Thanks for your advice Avendit. Having found an installer I am happy with, I guess that is probably worth more than trying to push for an extra 2-2.5kwh per day. Apparently, the JA Solar panels are his default choice, so I will trust in his advice.

I did consider waiting but like all things in life tech related, there is always something better around the corner. You have to choose a point to jump in!

 

[Andy718]

Do you mind sharing your ballpark quote for the panels installation please? I understand if you rather not. Thanks.

Do you mind sharing your ballpark quote for the panels installation please? I understand if you rather not. Thanks.

PM sent

 

[WannabeOwner]

I guess that is probably worth more than trying to push for an extra 2-2.5kwh per day

That's where my man-maths would be. 5% inflation, maybe more, over 20? years lifetime. Assuming paying "cash", rather than borrowing in order to purchase, I look at it as how it would compare return-on-investment compared to some other safe savings. Also, for anyone approaching retirement, how it locks-in the price and removes uncertainty of future costs. Even more apposite considering the recent, unanticipated, fuel price hikes.

Helps if it is the forever-home though, as resale value may not be great (but I suppose if it causes the buyer to buy your house, rather than the one next-door, that intangible value is worth a lot)

 

[Mrklaw]

Have an installer coming round to do a site inspection for battery initially. I’ll ask about north panels too while they’re here. Still don’t have more than two very similar but a little expensive feeling quotes but nobody is responding so I felt I had to at least move something forward a little.

The people coming round did a quote for Givenergy and pylontech. I mentioned I was leaning givenergy as they may need to go outside. He said they weren’t meant to be fully exposed, which I’m not sure is correct? And that the pylontechs could live in the loft - which I’m a little wary of as its quite warm in there in the summer (although shoudl be ok for electronic temps). They pylontechs are tempting as they’re relatively easy to expand so depending on how they go, I could add another one every year for a few years rather than a single big outlay

Anyone else have a battery setup in the loft?

 

[WannabeOwner]

shoudl be ok for electronic temps

At work we spend a lot of money on cooling to keep our servers cold (a temperature which isn't comfortable in shirt-sleeves). Apparently this prolongs their life ...

Dunno how that translates into the chips that are on batteries though.

 

[Mrklaw]

At work we spend a lot of money on cooling to keep our servers cold (a temperature which isn't comfortable in shirt-sleeves). Apparently this prolongs their life ...

Dunno how that translates into the chips that are on batteries though.

Good point and they’re designed to be running 24/7. I was thinking. ‘My PC is ok if you keep the temps below 70c and it’s probably only 30-40 max on a hot summers day in the loft..’ which May be the wrong way of thinking about it

 

[PITA]

Good point and they’re designed to be running 24/7. I was thinking. ‘My PC is ok if you keep the temps below 70c and it’s probably only 30-40 max on a hot summers day in the loft..’ which May be the wrong way of thinking about it

... IF .... you had a battery fire in the loft.

How easily could anybody get to it?

Our Powerwalls are installed outside for this reason.

Especially when you're placing these units in situ for potentially years to come...

I even had our Solar Inverter installed outside on our North Facing wall to keep cool.

 

[init6]

At work we spend a lot of money on cooling to keep our servers cold (a temperature which isn't comfortable in shirt-sleeves). Apparently this prolongs their life ...

Dunno how that translates into the chips that are on batteries though.

That's mainly because the servers generate a lot of heat and it doesn't take a long time with no aircon for them to overheat. IIRC the ideal datacentre temp is around 20C. It'll likely feel colder if there's a lot of air being pumped around the room.

So back to batteries, they won't generate as much heat and have quite a wide operating temp. (-25C-55C for GivingEnergy)
@PITA's concerns around fire safety and access for maintenance are likely a bigger worry.

 

[Tony Hoyle]

They don't keep datacentres that cold these days.. cheaper to let them warm up a bit - far less energy use (some places like googles use clever cooling systems that are a fraction of the cost to run but that takes a lot of investment that most datacentres don't have). Last one I was in a month or so ago was quite comfortable to be in... a few years ago if you had an install to do you'd need a coat!

 

[Mrklaw]

maybe I should installe them in the chimney

Curious how many are IP rated - pylon tech are clearly for internal installation and I don’t know if its more or less of a concern if they’re in the loft or the spare room/utility? (I don’t have a utility)

 

[WannabeOwner]

That's mainly because the servers generate a lot of heat and it doesn't take a long time with no aircon for them to overheat.

Good point, thanks.

So back to batteries, they won't generate as much heat and have quite a wide operating temp

Mine are in the far end "potting shed" room. Its a long way from house heating, but since putting 2x PowerWall in there it has kept a couple of degrees warmer in Winter, which has been a benefit compared to the losses associated with that distance radiator coming on!, and sufficiently "noticeably warmer" in Summer that I leave the internal door open. Not sure the heat is much, but that building is new, very well insulated, and so doesn't heat up dramatically in Summer Sun. Might a roof space be different? (dunno where/if operating temperature, and life-shortening temperature graphs cross?)