Solar Panels UK - is it worth it?

[phil4]

with todays forecast of sun and no cloud all day it’s got a good chance of topping the battery off by the time we all get home.

I've had solar since last Jan, and would say that forecasts are rubbish. Sure they might get a vague idea of whether it's going to be rain all day, 1-2kWh or sunnier 9-10kWh, but don't be relying on the actual number being anywhere near what is forecast, as it never seems to be... and this is using various different forecasts methods, including HA default, Solcast and various apps.

 

[Mrklaw]

Do octopus require MCS for the 15p rate? I know they've said they don't need MCS for SEG but do they limit you to the lower rates without MCS?

 

[ACarneiro]

Have you started that ball rolling with Octopus? Didn't take very long for me (rate limiting step was the DNO, as expected) and with the current generous export rate it's definitely worth exporting as much solar as possible

 

[notmeguv]

Have you started that ball rolling with Octopus? Didn't take very long for me (rate limiting step was the DNO, as expected) and with the current generous export rate it's definitely worth exporting as much solar as possible

I’m just waiting for some docs from the installer (schematic, MCS) so I can apply for the export MPAN. Should get those later today. They said they’re waiting for the DNO to respond to the notification of installation (for the SEG) which could be anything between one week and several weeks.

 

[WannabeOwner]

Until I get my export MPAN I really want to use all the solar I can and export none ideally.

Understood. The balance is to prevent it getting to 0% during Peak Rate. If you can comfortably live within 100% - 0% (or, allowing for AI to get it wrong 70%-0%) during the day that's easy. If not then, based on previous conversations here, you will be (financially) better off exporting-for-nought rather than failing to get to 100% when AI mis-forecasts

You could drop the reserve to e.g. 0% when you go to bed - assuming that if it did hit 0% before Off Peak starts, and you got a powercut but were asleep, you wouldn't mind

 

[phil4]

I’m just waiting for some docs from the installer (schematic, MCS) so I can apply for the export MPAN. Should get those later today. They said they’re waiting for the DNO to respond to the notification of installation (for the SEG) which could be anything between one week and several weeks.

Understood. The balance is to prevent it getting to 0% during Peak Rate. If you can comfortably live within 100% - 0% (or, allowing for AI to get it wrong 70%-0%) during the day that's easy. If not then, based on previous conversations here, you will be (financially) better off exporting-for-nought rather than failing to get to 100% when AI mis-forecasts

You could drop the reserve to e.g. 0% when you go to bed - assuming that if it did hit 0% before Off Peak starts, and you got a powercut but were asleep, you wouldn't mind

I agree, My comment about weather/solar predictions stems mainly from me trying to do just that. Until they changed the export rate, I was doing my best to use all solar (as export was 4.1p, but leccy cost was 7.5p)... but it was so hard to do, you'd almost certainly either over estimate the solar, charge too little, and end up using peak rate, or under estimating, filling the battery to 100% and then exporting. That was whether your let the powerwall manage it, or do it yourself. It just never seemed reliable enough.

 

[WannabeOwner]

It just never seemed reliable enough

Yup. I've been recording what Solcast predicted, what it thought actually happened (after the fact) and what actually happened (PowerWall record of the PV it saw). The 3 are in step a lot of the time, adrift by small enough not to substantively matter some of the time, but the "very different" is not a rare occurrence ...

What annoys me is that Solcast in Oz is a better predictor of Sun in UK than Met Office.

 

[PITA]

Glad to see I'm not the only considering the Apocalypse

I had a weird scenario not long back...

MyEnergi did a Software Update to Version 5 on the Zappi's...

It completely messed up our setup... throwing up errors like "Comms Lost"... "CT Lost"... "Site Limit Reached"... all sorts.

The immediate problem was the 7kW charger refused to dump the Solar being generated.

So I used the Commando Socket temporarily until we could figure out, and unravel all the software problems (which took two weeks...)

Totally unexpected... but having options saved the day...

 

[phil4]

I had a weird scenario not long back...
Totally unexpected... but having options saved the day...

I've got a gen2 tesla wall charger too, both show up as "house load" to the PW. So can run from solar or the PW as needed.

The downside on preping is I'm not clear how effective the PW would be with no connection to the mothership. Or the car for that matter. We'd likely be stuck on the PW with whatever settings it last had. And the car... well I expect it'd drive.

 

[yessuz]

it is very interesting point.
I was contemplating to install the 2nd charging facility at home. I currently have 7 kw Pod Point and though about commando socket (Or even Tesla wall charger).

but then I came to realization that most likely financially it makes very little sense (at least in my case).

Hypothetically, yes, it is great to have one. In case my Pod point will fail. but then, I looked at the costs.
To install 32 amp commando, I need additional breaker (or upgrade for the garage) but then again, the 32 amp blue adapted for mobile connector is out of stock (and is out of stock for the last year as long as I checked)
to install tesla wall charge, same comes to breaker. but then instead of 30 gbp for the socket, it is 470 for the charger.
Installation itself (unless you are electrician) is another 300-350. So you end up in region of 400-700 gbp.

Now, within 2 miles radius from home I have 2 x 170 kw pod point, 4 x 7 kw pod point, 4 x up to 150 kw ev charge points + 4 x up to 150 kw which are being commissioned at the nearest gas garage (instead of car wash...). so in low likelyhood event of it going down, in case I need an emergency charge - I have more than plenty fast charge options. and then if in no rush, granny charger will cover...

so in the end I took the sensible decision not to install any of those.. yet :/

 

[PITA]

it is very interesting point.
I was contemplating to install the 2nd charging facility at home. I currently have 7 kw Pod Point and though about commando socket (Or even Tesla wall charger).

but then I came to realization that most likely financially it makes very little sense (at least in my case).

Hypothetically, yes, it is great to have one. In case my Pod point will fail. but then, I looked at the costs.
To install 32 amp commando, I need additional breaker (or upgrade for the garage) but then again, the 32 amp blue adapted for mobile connector is out of stock (and is out of stock for the last year as long as I checked)
to install tesla wall charge, same comes to breaker. but then instead of 30 gbp for the socket, it is 470 for the charger.
Installation itself (unless you are electrician) is another 300-350. So you end up in region of 400-700 gbp.

Now, within 2 miles radius from home I have 2 x 170 kw pod point, 4 x 7 kw pod point, 4 x up to 150 kw ev charge points + 4 x up to 150 kw which are being commissioned at the nearest gas garage (instead of car wash...). so in low likelyhood event of it going down, in case I need an emergency charge - I have more than plenty fast charge options. and then if in no rush, granny charger will cover...

so in the end I took the sensible decision not to install any of those.. yet :/

In addition to using the 32 Amp Commando Socket for car charging...

I also use this socket to power Jet Washer, Dewalt 12" Drop Saw, Garden Lawnmower, vacuuming cars, and contractors use it for their power tools (if needed).

It's very versatile at 32 amps... and keeps the house locked up and secure when working outside. No trailing wires through doorways or windows...

It's wired into the Tesla Gateway on the backup side.

 

[WannabeOwner]

Garden Lawnmower

Blimey. that's "cabled" then? Very old school ... a Robot lawn mower would give you lots of new, unanticipatable, headaches to solve!

 

[yessuz]

In addition to using the 32 Amp Commando Socket for car charging...

I also use this socket to power Jet Washer, Dewalt 12" Drop Saw, Garden Lawnmower, vacuuming cars, and contractors use it for their power tools (if needed).

It's very versatile at 32 amps... and keeps the house locked up and secure when working outside. No trailing wires through doorways or windows...

It's wired into the Tesla Gateway on the backup side.

Well, i got 3 pin sockets behind garage (my bbq man-area) and it is enough to cover whole garden and drive for any lawn mowers, jet washers and such

 

[PITA]

Well, i got 3 pin sockets behind garage (my bbq man-area) and it is enough to cover whole garden and drive for any lawn mowers, jet washers and such

Yep me to... have six sockets scattered around the garden perimeter for Xmas lights and stuff... which if that's enough for you, fair enough.

 

[PITA]

Blimey. that's "cabled" then? Very old school ... a Robot lawn mower would give you lots of new, unanticipatable, headaches to solve!

I don't like to throw stuff away if it still works

 

[WannabeOwner]

I don't like to throw stuff away if it still works

Fair dos. I changed to Robot Mowers when my ride on got to the end of what I could keep limping along with multiple off-eBay donors

I used to mow the grass on a Friday night - ie.. likely we would have people coming at weekend. If raining Friday night had to do it Saturday morning ... when Missus would have quite liked some help getting ready ... Taking the cost of a new mower - old mower got the job done quickly, so new replacement was dear in order to have the same width / speed - and the 1.25 hours a week saved in the mowing season - I was about evens for the replacement. But the things run for several hours a night, 5 nights a week ... to do the job that took me an hour. OK they are very narrow, but their random pattern is ridiculous - in terms of battery run-time and degredation / longevity-lack, therefore. The software wins for "nearly right" - incredibly frustrating what they didn't do in the software that would have made it much better.

Hey ho ... something for you to look forward to when your mower eventually dies

 

[Js1977]

Hey ho ... something for you to look forward to when your mower eventually dies

His mower, if looked after, will carry on long before you and me. It's an irremediable fact....Just a reminder

 

[WannabeOwner]

His mower, if looked after, will carry on long before you and me. It's an irremediable fact....Just a reminder

Yeah ... good point. At least my mower was ICE so it shook and wore itself to bits and gave me a chance to upgrade to BEV Robot.

A mower with a cable is like a Hoover, electric mower not going to fail in a long long time. Poor sod will have to stroll up and down his lawn for decades to come doing manual labour, minding not to run over the cable ...

 

[Js1977]

Poor sod will have to stroll up and down his lawn for decades to come doing manual labour

Ive been reducing manual labour and chores for a few years now. Sometimes you have to be careful what you wish for... Sometimes when I bend down ill get stomach cramps, Ridding the motorbike will sometimes give me leg cramps, doing some work with the leaf blower the other day left me with a very sore arm and so on and so forth. At 46, this is a very poor show.. I might invest in a electric rowing machine

 

[GlynG]

Fair dos. I changed to Robot Mowers when my ride on got to the end of what I could keep limping along with multiple off-eBay donors

I used to mow the grass on a Friday night - ie.. likely we would have people coming at weekend. If raining Friday night had to do it Saturday morning ... when Missus would have quite liked some help getting ready ... Taking the cost of a new mower - old mower got the job done quickly, so new replacement was dear in order to have the same width / speed - and the 1.25 hours a week saved in the mowing season - I was about evens for the replacement. But the things run for several hours a night, 5 nights a week ... to do the job that took me an hour. OK they are very narrow, but their random pattern is ridiculous - in terms of battery run-time and degredation / longevity-lack, therefore. The software wins for "nearly right" - incredibly frustrating what they didn't do in the software that would have made it much better.

Hey ho ... something for you to look forward to when your mower eventually dies

Sounds like you should have bought the Bosch Indego Robot Mower - they mow in straight lines after mapping the lawn. Bosch claim each cut adds to the stored mapping to improve the efficiency of the cut, however I'm convinced that's just marketing bull.

Robot mowers are pretty slow but they don't need to do a quick job, they go home to base as and when they need a charge, once done they park up on the charger ready for the next deployment - and with Bosch you can leave the frequency to the software, It links your location to the weather and decides when to cut - usually 2 or three times per week but obviously dependant on lawn size.

The only issue with robot mowers is they don't cut very low and the perimeter cable needs to be buried unless your fine with occasional damage to the wire, they don't cut very well close to the edge of the lawn either - so my solution was to use driveway blocks to form the edging set flush to the grass.
My current Indego S+500 has been modified by me to cut a bit lower than the 30mm which is the Bosch lowest cut, i like really close cutting.
The Bosch weather cover over the base plate/charger is absolute rubbish - a waste of £120 - so i built a proper garage/home for it - with pitched roof and auto door closing when the mower goes home - and the actual door was made to look like a proper Georgian garage door painted white.