solar pv

merc07

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Excess energy can go to storage batteries, Tesla Powewall being one type. Our local council has just started a group buy scheme for those who wish can join up and benefit from significant discounts on purchase and installation (not necessarily Tesla) . So one can still receive payment for excess generated electricity (in my case deemed to be 50% of the total generated) and store it for use later at home. Win, win
What cost are we talking for batteries?

I am also paid at 50% generation but use as much as the max 25kw a day I can from my 11 panels (24.7kw today) - I need another 6 panels !

My bespoke software/hardware switches appliances on/off remotely as power becomes available. I still have times between switching that could be stored but the cost is just not worth it.

A neighbor of mine still has the old type meter which goes backwards when more power is available than used - the ultimate free battery storage...
 

DrNick

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Excess energy can go to storage batteries, Tesla Powewall being one type. Our local council has just started a group buy scheme for those who wish can join up and benefit from significant discounts on purchase and installation (not necessarily Tesla) . So one can still receive payment for excess generated electricity (in my case deemed to be 50% of the total generated) and store it for use later at home. Win, win
Yes, but the question was about why the feed in tariff hasn’t gone up over the years.
Batteries are changing the landscape but are difficult to justify on a purely financial basis, especially Powerwall unless you have one of the special Tesla only tariffs. My batteries have probably extended my Pay back period by a couple of years, but sometimes it’s not all about the money!
If electricity carries on going up the economics will change again.
New systems can only get SEG payments which are 4p /unit or less, but as installation costs have fallen, the incentives have been removed. If you are on the old FIT scheme then you are on a good deal, especially if you are on the 50% unmetered one.
 

DrNick

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What cost are we talking for batteries?

I am also paid at 50% generation but use as much as the max 25kw a day I can from my 11 panels (24.7kw today) - I need another 6 panels !

My bespoke software/hardware switches appliances on/off remotely as power becomes available. I still have times between switching that could be stored but the cost is just not worth it.

A neighbor of mine still has the old type meter which goes backwards when more power is available than used - the ultimate free battery storage...
About a grand per kWhr but you will also need a hybrid inverter. Cost reduces as you get bigger batteries but they are not cheap.
An option is you can get an EV that is home connectable so you can use it’s battery to power your house. Ok if you don’t drive it around that much!
 

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We may add batteries to our solar - we have an 8.8kwp array, in practice 7.4 due to the limitations of the microinverters. First season for us so we are gathering data. We use our EVs as a way to catch the spare production to avoid export - so far it’s working fairly well and keeping exports really low, but the picture may well change in the winter. Driving on sunshine is rather nice!
 

merc07

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We may add batteries to our solar - we have an 8.8kwp array, in practice 7.4 due to the limitations of the microinverters. First season for us so we are gathering data. We use our EVs as a way to catch the spare production to avoid export - so far it’s working fairly well and keeping exports really low, but the picture may well change in the winter. Driving on sunshine is rather nice!
Is there not a 3.6kw max allowed per household, do you have to get approval for anything greater ?
 

BTB 500

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Yes, but the question was about why the feed in tariff hasn’t gone up over the years.

The tariff does get adjusted (but of course the export rate is still tiny compared to what you pay to import):


If you are on the old FIT scheme then you are on a good deal, especially if you are on the 50% unmetered one.

Over the year we export around 80% of what we generate (3.3 kW installation), so would be better off using export readings from our smart meter than the deemed 50% export rate. I applied for this in January and it's still 'ongoing'. Our FIT account has been locked since then pending the change, so we've not received a penny since December :( This is with Scottish Power ... don't know if the other companies are as bad.
 

DrNick

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Is there not a 3.6kw max allowed per household, do you have to get approval for anything greater ?
I think its only supplying back to the grid. You can generate as much as you like from solar cells but you are capped at what you can export back to the grid unless you get permission in advance
 

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Is there not a 3.6kw max allowed per household, do you have to get approval for anything greater ?
No, there’s no limit but any installation over 3.6kWp does require approval from the DNO. It’s not hard to get, and your MCS registered installer handles the paperwork.

The logic is that vary thing produced might be sent back down the wire to the grid, and the local grid needs to be able to handle it. We could well be exporting at 7kW if we are away on hols, for example.
 

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No, there’s no limit but any installation over 3.6kWp does require approval from the DNO. It’s not hard to get, and your MCS registered installer handles the paperwork.

The logic is that vary thing produced might be sent back down the wire to the grid, and the local grid needs to be able to handle it. We could well be exporting at 7kW if we are away on hols, for example.

Some friends in Wales recently installed a 10 kW system ... their energy company simply imposed a (pretty restrictive) export cap. After a lot of negotiating they managed to get that doubled, although in reality they don't plan to export much (they have a battery system).
 

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Eon now realised their mistake and have emailed to say that they have cancelled one of the cheques. But they haven’t said which one:wallbash::doh:
 

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Any excess energy is diverted to the hot water tank via a Solar iboost so we have lots and lots of hot water all through the spring and summer.
I’m interested in your solar iBoost - sounds more sophisticated than our system. I’ve tried contacting that company but have had no reply so perhaps you can help.
As well as the iBoost feeding the immersion heate, I need to have the immersion heater on once a week on a time clock. Does the iBoost have a time clock built in?
 

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I’m interested in your solar iBoost - sounds more sophisticated than our system. I’ve tried contacting that company but have had no reply so perhaps you can help.
As well as the iBoost feeding the immersion heate, I need to have the immersion heater on once a week on a time clock. Does the iBoost have a time clock built in?
My iboost only has a manual boost feature, you can select the boost from 15 mins to 2 hours.
It looks like the new version, the iboost+, has a built in programmer so can be preset it to heat the immersion when needed.
Solar iBoost+ | Solar Immersion Controller - Heater Shop
My immersion is heated with a top mounted element, so to get the maximum benefit from the solar I replaced the short length element with the larger 3 foot element.
 

Piff

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My immersion heater is in the bottom of the cylinder and to use solar electric without drawing from the grid it was replaced with a 1.5kw one..
So once a week we run it overnight to to kill off potential legionnaires disease (Ashp only heats to about 50 degrees)
with the solar iBoost - do you think I would be better changing back to the 3kw one?
 

geoffus

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My immersion heater is in the bottom of the cylinder and to use solar electric without drawing from the grid it was replaced with a 1.5kw one..
So once a week we run it overnight to to kill off potential legionnaires disease (Ashp only heats to about 50 degrees)
with the solar iBoost - do you think I would be better changing back to the 3kw one?
Yes indeed, the iBoost varies the amount of power going to the element, up to 3kw when your solar is producing excess energy.
We also have the element thermostat set higher than the central heating cylinder stat, this makes sure the gas boiler doesn't fire up unnecessary, the cylinder is also triple wrapped with insulation to prevent heat losses overnight.
 

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Eon now realised their mistake and have emailed to say that they have cancelled one of the cheques. But they haven’t said which one:wallbash::doh:
So I asked which one and a few days later they said both and said they would issue a new one
Weeks later I chased them up again. They replied and said the payment was approved on 8/6/22 and I should receive a cheque within 21 days. I pointed out that I should have received by 29/6/22. They then said 21 "working" days. I asked how many days a week they worked as if it was only 5 my cheque should have arrived by 7/7/22 (which it hasn't). If they only work 5 days a week how do we get electricity on Saturdays & Sundays? Even the postman works 6 days a week for regular mail.
They then replied that FIT rules allow them up to 60 days to process a payment and provided contact info for their complaints dept.
Complaints dept admit that they have made a big co*k up in transferring customers banking data to a new system so have issued cheques which they have also co*ked up. They are working on it but can't advise when it will be sorted
 

Piff

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So I asked which one and a few days later they said both and said they would issue a new one
Weeks later I chased them up again. They replied and said the payment was approved on 8/6/22 and I should receive a cheque within 21 days. I pointed out that I should have received by 29/6/22. They then said 21 "working" days. I asked how many days a week they worked as if it was only 5 my cheque should have arrived by 7/7/22 (which it hasn't). If they only work 5 days a week how do we get electricity on Saturdays & Sundays? Even the postman works 6 days a week for regular mail.
They then replied that FIT rules allow them up to 60 days to process a payment and provided contact info for their complaints dept.
Complaints dept admit that they have made a big co*k up in transferring customers banking data to a new system so have issued cheques which they have also co*ked up. They are working on it but can't advise when it will be sorted
Now they have been in touch again to advise that they didn't cancel both cheques and one of them is still valid :wallbash:
 

Piff

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Fitted the Solar iBoost+ on Sunday together with the 3kw immersion heater. Very pleased with the results, 60 degree water yesterday & today without the ASHP running as far as I am aware.
Only slight disappointment is that The Solar iBoost+ timeclock only programs in blocks of Mon-Fri and Sat-Sun. We could do with just one "on" period on a Friday night/Saturday morning.
I know that the stat in the immersion heater will cut out when the water is up to temperature but I would like to know if it is possible to calculate how long it takes a 3kw immersion heater to raise a 300litre unvented cylinder from 50 degrees to 60 degrees.
 

190

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but I would like to know if it is possible to calculate how long it takes a 3kw immersion heater to raise a 300litre unvented cylinder from 50 degrees to 60 degrees.

Ignoring insulation losses.

It takes 0.0011626 KWh to raise 1 litre of water 1 deg C

So 300 litres through 10 deg C will take 0.0011626 x 300 x10 = 3.488 KWh or 1 hour 10 mins for a 3KW heater
 

BTB 500

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A £593 FIT payment from Scottish Power appeared in my bank account today - no paperwork yet to say what period it covers though!
 

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