Soldato
Ive got it in the back of my mind there is a 1 month cool off when coming off an octopus tariff before you can move to another
The other consideration is if they will deffo let you back on go later, thats the risk
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
- Start date
Ive got it in the back of my mind there is a 1 month cool off when coming off an octopus tariff before you can move to another
The other consideration is if they will deffo let you back on go later, thats the risk
I have my post-site survey quote back for my solar system.
They have quoted for panels on our West roof as well as the South, and quoted for upgrading to a hybrid inverter.
Just the 9 panels on the South roof is £6,720
Adding the 6 panels on the West roof and switching to a hybrid inverter makes it a total of £9,120.
That gives a total of 15 panels for 5.925 kWp. And they're estimating the West facing panels to be about 90% as productive as the south facing. (Well, strictly speaking they are, respectively, 70 and 20 degrees from due South.)
This does make me wonder about our plan to leave the batteries for now. The intention was to wait and see what we're generating versus what we're using. But (assuming they can be trusted) details from our smart meter suggest that even with the two of us in the house using our work laptops, our base usage is still only about 200W. So surely we're going to be exceeding that in production (and therefore would be making use of the batteries) for parts of most days?
Because, of course, the fault in the idea of checking our figures achieved and then fitting batteries later is that it would probably mean paying VAT on the batteries as they wouldn't be installed alongside a panel array.
They have quoted for panels on our West roof as well as the South, and quoted for upgrading to a hybrid inverter.
Just the 9 panels on the South roof is £6,720
Adding the 6 panels on the West roof and switching to a hybrid inverter makes it a total of £9,120.
That gives a total of 15 panels for 5.925 kWp. And they're estimating the West facing panels to be about 90% as productive as the south facing. (Well, strictly speaking they are, respectively, 70 and 20 degrees from due South.)
This does make me wonder about our plan to leave the batteries for now. The intention was to wait and see what we're generating versus what we're using. But (assuming they can be trusted) details from our smart meter suggest that even with the two of us in the house using our work laptops, our base usage is still only about 200W. So surely we're going to be exceeding that in production (and therefore would be making use of the batteries) for parts of most days?
Because, of course, the fault in the idea of checking our figures achieved and then fitting batteries later is that it would probably mean paying VAT on the batteries as they wouldn't be installed alongside a panel array.
Soldato
far far away..
Why is the two arrays and inverter that much? Can you break down the costings. I have similar equipment and the all in cost was near your first figure so I want to make sure what your paying for.
Ha! Didn't even spot that as I was typing it.
The £6,720 cost is for a full system, including 9 JA solar 395 panels and inverter.
£1,750 cost for the panels on the West roof (including additional scaffolding).
£650 to upgrade the inverter to a hybrid one.
It's not itemised with any more detail than that unfortunately. I will be speaking to them in the next couple of days to finalise the design, so will be asking questions then.
The £6,720 cost is for a full system, including 9 JA solar 395 panels and inverter.
£1,750 cost for the panels on the West roof (including additional scaffolding).
£650 to upgrade the inverter to a hybrid one.
It's not itemised with any more detail than that unfortunately. I will be speaking to them in the next couple of days to finalise the design, so will be asking questions then.
Soldato
Looking across November so far, about 12kWh per day average. (And checking August to make sure of seasonal variation - not much difference.)
Looking at a day in detail though, it's very low across the day with peaks morning, mid-day and evening.
Actually, I think I am seeing that I've made an error. The 'base' level is showing at around 0.2kWh - but each segment is referring to a 30 minute period of time, so I guess the base load is actually about 400W, right?
That's still going to result in us generating more than we're using though.
Looking at a day in detail though, it's very low across the day with peaks morning, mid-day and evening.
Actually, I think I am seeing that I've made an error. The 'base' level is showing at around 0.2kWh - but each segment is referring to a 30 minute period of time, so I guess the base load is actually about 400W, right?
That's still going to result in us generating more than we're using though.
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Soldato
Best to work out some figures based on cost, expected generation, export proceeds etc, should give you some idea of ROI timeframe.
Your baseline sounds like more like 400w yes, which isn't dissimilar to mine, and this level works pretty well with solar.
You'd do fairly well with a 4kw~ system based on my generation to date, going much higher you sort of need a plan for the excess generation, whether it's battery, or EV charge, or eddi for hot water. If you want to add more stuff later then gunning for a larger system can be a good future investment, as you don't want to mess about with updating things too much once they're installed.
SEG payments for export are fairly rubbish, especially if you wind up on something like Octopus Go where you only get 4.1p/kwh payments, but if you overspec the generation side you could stick on something like agile or cap tariff and get paid better for excess generation (static at 15p/kwh currently).
I can probably give you some idea of how a 4-5kwp system will do with or without a battery, at least for the last few months.
September
Generation: 375 kwh
Solar to home: 195 kwh (52%)
Solar to battery: 153 kwh (40%)
Solar to Grid: 27 kwh (7%)
October
Generation: 313 kwh
Solar to home: 160 kwh (51%)
Solar to battery: 103 kwh (32%)
Solar to Grid: 50 kwh (15%)
November (to date)
Generation: 119 kwh
Solar to home: 71 kwh (59%)
Solar to battery: 42 kwh (35%)
Solar to Grid: 6 kwh (5%)
Summary is that by having a baseline of around 400W and then doing my best to use excess generation when available for random things like appliances, my solar usage from generation is between 50-60% as it's generated. 30-40% gets sent to battery, and then 5-15% I can't use and it goes to grid.
Where the battery comes into it's own is with days where generation is very up and down, this means that the battery smooths everything out, and you can store excess for later or take advantage of time of use off-peak tariffs like Octopus Go to boost overnight.
Your baseline sounds like more like 400w yes, which isn't dissimilar to mine, and this level works pretty well with solar.
You'd do fairly well with a 4kw~ system based on my generation to date, going much higher you sort of need a plan for the excess generation, whether it's battery, or EV charge, or eddi for hot water. If you want to add more stuff later then gunning for a larger system can be a good future investment, as you don't want to mess about with updating things too much once they're installed.
SEG payments for export are fairly rubbish, especially if you wind up on something like Octopus Go where you only get 4.1p/kwh payments, but if you overspec the generation side you could stick on something like agile or cap tariff and get paid better for excess generation (static at 15p/kwh currently).
I can probably give you some idea of how a 4-5kwp system will do with or without a battery, at least for the last few months.
September
Generation: 375 kwh
Solar to home: 195 kwh (52%)
Solar to battery: 153 kwh (40%)
Solar to Grid: 27 kwh (7%)
October
Generation: 313 kwh
Solar to home: 160 kwh (51%)
Solar to battery: 103 kwh (32%)
Solar to Grid: 50 kwh (15%)
November (to date)
Generation: 119 kwh
Solar to home: 71 kwh (59%)
Solar to battery: 42 kwh (35%)
Solar to Grid: 6 kwh (5%)
Summary is that by having a baseline of around 400W and then doing my best to use excess generation when available for random things like appliances, my solar usage from generation is between 50-60% as it's generated. 30-40% gets sent to battery, and then 5-15% I can't use and it goes to grid.
Where the battery comes into it's own is with days where generation is very up and down, this means that the battery smooths everything out, and you can store excess for later or take advantage of time of use off-peak tariffs like Octopus Go to boost overnight.
Missed a pallet delivery today which was a total surprise for me…
Spoke to my installer and he was as surprised as I was - apparently he had enquired about availability and current price of the puredrive storage batteries and Solis inverter at the weekend, his supplier had then taken it upon themselves to create and ship an order without being asked.
He didn’t know whether to be more surprised that they had unilaterally decided to ship an order without being asked or that they actually had it all in stock immediately to ship.
Funnily enough we still hadn’t locked down the final equipment because we were waiting on prices and availability of the new qcell storage and hybrid inverter. He has said to just take delivery though and if I decide to go with the QCell he’ll take the other stuff away.
Spoke to my installer and he was as surprised as I was - apparently he had enquired about availability and current price of the puredrive storage batteries and Solis inverter at the weekend, his supplier had then taken it upon themselves to create and ship an order without being asked.
He didn’t know whether to be more surprised that they had unilaterally decided to ship an order without being asked or that they actually had it all in stock immediately to ship.
Funnily enough we still hadn’t locked down the final equipment because we were waiting on prices and availability of the new qcell storage and hybrid inverter. He has said to just take delivery though and if I decide to go with the QCell he’ll take the other stuff away.
Soldato
Yup.
We don't have a battery and it's those days with sunny spells and clouds that really get you.
You generate 3kw or whatever, most of which is going to the grid, which you are getting nothing for, a cloud comes over as you put the kettle on and now your pulling from the grid.
That being said, assuming you don't have a way of pulling a cheap rate at night, given generation this month, a battery would be doing little.
Soldato
you get 15p/kwh with export via octopus outgoing, not exactly nothing.....so if exporting 3kw thats 45p, more than enough to cover that boiling kettle
Soldato
Mrs doesn't want to get a smart meter, I must admit I'm somewhat hesitant myself, keep hearing too many horror stories.
Soldato
To be fair there were a few really dodgy installations that caught fire in the early days but I don’t think anyone died.Didn't you hear about the case of the serial killer smart meter?!
Soldato
You can't run them backwards.
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Soldato
Maybe they should rename Smart Meters to "Meters for people who are Intelligent".
Soldato
Yeah definitely drop the smart brand.
Soldato
so its a choice to get nothing for your excess solar then....so can't really complain. Had mine fitted years ago and had newer ones fitted a fortnight ago, not sure what the issues with them are tbh
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