Solar panels and battery - any real world reccomendations?

[Journey]

@Journey have you got any pictures of your setup? It's one thing I haven't considered yet.

No recent ones just a few from mid-install, Ill put some up once I clear out the garage (where it all is) as we are having building work done and I literally can't get through the door right now, just hope we don't have a fire.

I actually was going to make a thread about it as someone else asked, just one thing has lead into another and we've had some trades people delays which has further pushed things back, and then the weather has also stopped play. I'm also wanting new glazing this year/next, I think I just like punishing myself with moving stuff and making life as disrupted as possible.

 

[Ron-ski]

Whatever you do, make sure they fit bird guards around your panels. We had panels fitted in 2015, and the installer never suggested bird guards, but within a couple of years we had loads of pigeons nesting under them, the cooing noise drove me mad. I ended up installing a combination of netting and bird spikes which did the job, not easy from a ladder. It was funny watching the pigeons walking back and forth trying to work out how to get underneath, they seemed to do this regularly for a few months, but I rarely see one up there now.

I spoke to our installer (The Little Green Energy Company) why they didn't quoted for bird guards, they said that it had only recently become a problem, which seemed a bit odd to me.

I never had a battery fitted, but am starting to wonder if its worth it now, especially if it can be charged at a cheap rate overnight, the winter months don't produce a lot, and its when you use it the most.

 

[SoliD]

No recent ones just a few from mid-install, Ill put some up once I clear out the garage (where it all is) as we are having building work done and I literally can't get through the door right now, just hope we don't have a fire.

I actually was going to make a thread about it as someone else asked, just one thing has lead into another and we've had some trades people delays which has further pushed things back, and then the weather has also stopped play. I'm also wanting new glazing this year/next, I think I just like punishing myself with moving stuff and making life as disrupted as possible.

Thanks, will see what they suggest when they come out,suspect loft will be best bet, but ac unit is up there so they may say otherwise as space is limited and low pitch.

 

[ShadowMan]

Had a quote from UPS Solar and TCL Solar and gave approval to TCL to go ahead. 5.2kw solar array with no battery at this stage. With working from home all day and easily able to move washing and dishwasher to daily load rather than overnight hoping for some savings. Will be adding a battery in future as was advised prices inflated at the moment due to supply so best to wait and get a better deal with more capacity in a year or 2 hopefully.

 

[Journey]

Had a quote from UPS Solar and TCL Solar and gave approval to TCL to go ahead. 5.2kw solar array with no battery at this stage. With working from home all day and easily able to move washing and dishwasher to daily load rather than overnight hoping for some savings. Will be adding a battery in future as was advised prices inflated at the moment due to supply so best to wait and get a better deal with more capacity in a year or 2 hopefully.

You'll miss out on the 5% VAT rate on the battery, if you don't do it with the solar, also you'll need a separate charge controller/inverter which add more costs. You should get a quote for one separately and see what the real cost is based on your current suggested solar install.

 

[GinG]

Had a quote from UPS Solar and TCL Solar and gave approval to TCL to go ahead. 5.2kw solar array with no battery at this stage. With working from home all day and easily able to move washing and dishwasher to daily load rather than overnight hoping for some savings. Will be adding a battery in future as was advised prices inflated at the moment due to supply so best to wait and get a better deal with more capacity in a year or 2 hopefully.

I'm not sure this is a good idea. As journey says you will miss out on the 5% Vat savings and due to no FIT payments you only get £0.055 per kWh extra generated.

Has the company done you a comparison of solar Vs battery and solar?

 

[ShadowMan]

They didn’t quote yet but I’ll ask about it. They said around £3500 for an 8.2kw battery and realistically unless it pays back quickly I have other things to spend that on (new bathroom). I’ve got my 30min readings for last 12 months downloaded and into powerbi to look at the usage amounts per time period and trends etc.

The VAT is annoying but as technology improves I’m hoping to get more for my money later anyway.

I’ll get numbers checked and see what comes out.

 

[GinG]

So I've recalculated my energy usage as I'm back online with my Avro login details and could see some of my previous statements.

I'm now looking at 5000-5500kwh household consumption so I'm now leaving towards the lower scale of panels.

I've had a quote for 10x455W panels, 3.6 GivEnergy inverter and 8.2 batter for £8157.

I'm waiting for a price back on the same panels but Solax battery and inverters.

My thoughts are that any more panels I'm just going to be at a loss...the wife works Mon-Fri so the car would only likely be plugged in on weekend days and would allow me to keep with the 8.2 battery.

The other option is to go down to 5.2 battery as this would bring cost down to £7,390 which would then allow more in the pot for garage conversion.

I downloaded Octo Compare which gives me average baseload as 122W. So this setup would more than do us to help bring our costs down but still rely on the grid.

Issues come at night and morning with showers and oven but again mainly in winter.

Financially I know I'm based going all out initially but one bug bare in the house is the lack of play room for the kids...I'm thinking either will help reduce our costs it's just how much compromise I go for now.

 

[GinG]

What's the best way to work out what is most beneficial?

Over last 12 months I've used around 14.45kwh per day average per day.

Company A is quoting based on the 10 x 455W panels that it will generate 3658kwh.

This works out on average over 12 months at 10kwh per day.

Therefore I am down around 4.45kwh per day?

I can then top this up with a battery...a 5.2kwh will cover this?

Therefore over the year can I assume 5.2kwh X £0.075 (overnight charge) X 7 days x 365days = £141.96 worth of leccy?

I then need to add on a few KWh per day based on what the inverter can pull when we use the shower and cooker to then work out if the 8.2kwh is worth going for? The difference is £767 between the size of battery.

This is average over 12 months...am I missing something here and is it much more complicated??

 

[b0rn2sk8]

You need to consider that in summer you may produce 40+ kWh in a day and most of that could be exported if not used or stored locally. In winter you may only produce 0.4wh in the whole day.

You can’t really look at as an average over the year as you’ll be getting the most sun when your consumption is the lowest.

 

[GinG]

You need to consider that in summer you may produce 40+ kWh in a day and most of that could be exported if not used or stored locally. In winter you may only produce 0.4wh in the whole day.

You can’t really look at as an average over the year as you’ll be getting the most sun when your consumption is the lowest.

Ok thanks for that...

Still absolutely baffled by it all then!! Haha.

 

[Foghorn Leghorn]

What's the best way to work out what is most beneficial?

Over last 12 months I've used around 14.45kwh per day average per day.

Company A is quoting based on the 10 x 455W panels that it will generate 3658kwh.

This works out on average over 12 months at 10kwh per day.

Therefore I am down around 4.45kwh per day?

I can then top this up with a battery...a 5.2kwh will cover this?

Therefore over the year can I assume 5.2kwh X £0.075 (overnight charge) X 7 days x 365days = £141.96 worth of leccy?

I then need to add on a few KWh per day based on what the inverter can pull when we use the shower and cooker to then work out if the 8.2kwh is worth going for? The difference is £767 between the size of battery.

This is average over 12 months...am I missing something here and is it much more complicated??

Sadly it doesn't work like that, through the summer months you'll generate the bulk of the power and won't be able to use/store most of it, through the winter months you're generation will be much lower (I see approx 85kwh per month from 1st November to end of January) with some days only seeing 100-200wh

 

[GinG]

Sadly it doesn't work like that, through the summer months you'll generate the bulk of the power and won't be able to use/store most of it, through the winter months you're generation will be much lower (I see approx 85kwh per month from 1st November to end of January) with some days only seeing 100-200wh

What sort of system have you got for that sort of generation?

 

[Foghorn Leghorn]

What sort of system have you got for that sort of generation?

4.2kwh system.
14 off 300w panels connected to a solar edge inverter, fitted in November 2018 and averages 4MWh per year since fitted.

 

[Journey]

Ok thanks for that...

Still absolutely baffled by it all then!! Haha.

Low generation days in winter are where the bigger battery will pay for itself faster, and in summer it is where the solar will pay for itself faster, that is the best way to look at it, in the most simplistic terms. If you can even trickle charge the bigger battery in winter during the few sun hours you have, you might put 4kW in or less, but that would give you enough to run your house in the evening and if you can get on Go Faster (20:30-01:30 if they still have that time slot) and then charge the battery and do all your heavy drain appliances in that time period (like i do). You then have a full pack for the morning which contributes to water-heating/shower use/kettle etc. rinse and repeat, someday you'll come home to a full pack, others days you'll be thinking wtf.

In summer you'll end up with a full pack pretty much always, and be running the house from the solar (+some battery) all day, and be exporting many kWh at 5.5p (not great) you'll not need to drain from the grid to the pack at all for the longer summer days unless you have a particularly energy heavy night.

There's more to it, I am still gathering data from my own system, but obviously I still haven't had it a full year (not even close) but I am trying to be proactive about maximising my generation/off-peak grid usage.

 

[GinG]

Thanks both...

I think I'm understanding it more now.

I'm now leaning in the 4.55kwh panels and 8.2kwh battery @ £8,157.

Even if between Nov-Jan going off maybe average of 85kwh per month generation leaves around 340kwh short.

230kwh can be used from battery an even on latest price of £0.075 would be £17.25 and then 110kwh @ £0.30 would cost around £30 so £37.25 in electric.

5.2 battery would be £69.45 worth of electric.

That's around £100 saving just over them 3 months...

Appreciate its all 'back of a fag packet' calculations but thats quite a bit of savings just over 3 months.

Even if you say over the year it may allow around £200 savings it's just a 3 year payback difference between the 2 battery sizes without any other increases taking place.

 

[Unseul]

Thanks both...

I think I'm understanding it more now.

I'm now leaning in the 4.55kwh panels and 8.2kwh battery @ £8,157.

Even if between Nov-Jan going off maybe average of 85kwh per month generation leaves around 340kwh short.

230kwh can be used from battery an even on latest price of £0.075 would be £17.25 and then 110kwh @ £0.30 would cost around £30 so £37.25 in electric.

5.2 battery would be £69.45 worth of electric.

That's around £100 saving just over them 3 months...

Appreciate its all 'back of a fag packet' calculations but thats quite a bit of savings just over 3 months.

Even if you say over the year it may allow around £200 savings it's just a 3 year payback difference between the 2 battery sizes without any other increases taking place.

And of course, what people seem to forget sometimes, is after that payback time, it's still benefitting you, instead it's simply straight cash in your pocket.

 

[HungryHippos]

My biggest hold up with batteries at the moment is that without a good tariff that lets you charge them up cheaply, they aren't as good. You are beholden to the tariffs available and hoping they don't pull the rug out from under you with regards to cheap off peak pricing.

@Journey what tariff are you on? Octopus Go? If so what is this tariff going to look like after April if the cap changes?

 

[Journey]

@Journey what tariff are you on? Octopus Go? If so what is this tariff going to look like after April if the cap changes?

Same as it is now for me, new customers are currently being offered 7.5p off peak and 30p peak, not sure on the standing charge.

I know someone who has just had 15kWh of batteries installed at only £5.7k including inverter and charge controller etc. Costing him £1.12 to charge vs £4.50, so a saving of £1233 per year based on the peak rate at 30p, he uses about 19kWh a day but it's trying to reduce some peak use and shift that as well.

He's not getting solar until his extension is done in 2023/4 and gets a new roof.

 

[Unseul]

Same as it is now for me, new customers are currently being offered 7.5p off peak and 30p peak, not sure on the standing charge.

I know someone who has just had 15kWh of batteries installed at only £5.7k including inverter and charge controller etc. Costing him £1.12 to charge vs £4.50, so a saving of £1233 per year based on the peak rate at 30p, he uses about 19kWh a day but it's trying to reduce some peak use and shift that as well.

He's not getting solar until his extension is done in 2023/4 and gets a new roof.

Where, who and what??? That's a very impressive price and I'm hoping to get batteries in our new place along with solar.