Soldato
What was your investment in all of that - Solar, battery, BEVs, Heat Pump (including install costs)?
Energy Prices (Strictly NO referrals!)
- Thread starter DXP55
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What was your investment in all of that - Solar, battery, BEVs, Heat Pump (including install costs)?
Soldato
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which is the rub...... if you have the money to play the long game you can do all these things... high initial costs that pay back over a 8 - 10 year period (and after that it is all sunny uplands!)
but people who are scrabbling around just to pay to get a hot meal on their table wont have the option.
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Soldato
True - also the people don't use much electricity don't get much benefit as the payback timescale is approaching the lifetime period of the equipment (solar panels for instance)
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Soldato
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not really..... obviously it depends how things go in the future, but actually right now i try to use as little of the solar energy that i generate as i can.... The reason being, during the day (when my panels are generating) electricity costs more than at night, so i use as much electricity as i can from 11:30pm - 5:30am at 7p kwh.
however any electricity that i generate but do not use, i can sell at 15p kwh.
as such if you can afford the system, even a low electricity user can be quids in over the long term, and also help decarbonise the grid at the same time.
The lifetime of panels these days is like 30 years, a lot of the return will come from the exported energy as well. Its viable even for low users.
When I say lifetime as well I mean efficiency drops to something like 80%, they dont just stop working.
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Soldato
I wonder if that will shift in the future.... The night time rate is cheaper due to lower usage but, as more people time-shift their usage to benefit from that, will this period reduce until its not there... Also - as more people get solar and export during the day (if they are not home and full or no battery, will generation become so high from domestic supplies that they lower the cost? (a long way to go for that, sure - its a hypothetical)
I dont have Eco7 meters -same charge at all times.
Soldato
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long term that is the goal (of the energy suppliers... its not my goal
)however with a modern electricity grid i believe (hope) there will be variable electricity costs for a good while yet. it may not be as simple as 11:30-5:30 (and indeed now we see plunge pricing and agile tarrifs for those who want to micromanage)
but i can imagine a scenario where you always have your car plugged in when its at home and you may not have any idea when it will charge, but it will just do it when electricity is at its cheapest. those of us with home batteries may need to have something like homeassistant running on a raspberry pi, which can charge and discharge our house battery and run the washing machine / tumble drier/ hot water system when needed (and it will monitor costs live), as well as make sure the central heating does not run at the most expensive times etc.
the timings may become more complex (hence needing to be computerised) but i believe there will still be ways to minimise our costs if we have the equipment to make the most of it.
dont forget tho. Domestic is a small part of our electricity usage. industry uses a lot more and that tends to be higher during the day.
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Soldato
Any idea on average maintenance costs over that 30 years?
EDIT: For clarity, I am not trying do any form of "gotcha".... I am just wondering what the payback term for my own circumstances would be.
6 panels (perhaps 7) on a directly South facing pitched roof (probable about 40deg pitch) and no obstructions in the way (trees etc) and annual usage at 1,500kWh
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Soldato
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i think my parents solar and battery has a......... its either 8 or 10 year warranty. (this is better than mine which is only 5 years) but for those years its zero.
their marketing was that that should mean that there is almost no chance of them ending up not making their money back in that period
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Heat pump was £3500 installed after the grant. No pay back expected for a normal person as running costs are on par with a modern gas boiler when electricity is 4X the price of gas.
However, my average electricity cost is significantly lower due to solar so it’s a lot cheaper to run than gas. In any case, it was cheaper to install than updating my existing 20 year old gas system which was an unusual appliance (100L heat store with integrated boiler).
Solar was £16k, it’s a big system (23 panels and a 13.5kwh battery) with premium features like whole home back up if the power goes out.
It could have been done cheaper but I wanted a toy to play with. Prices have come down a lot since, I think you could get an equivalent system for around £14k, certainly under £15k. A system without the whole home back up is probably closer to £13k.
Pay back is about 7-8 years for me but it depends on how the energy price moves and how many winter savings sessions there are where I can dump it to the grid.
Combining time of use tariffs and solar/battery system will also cut the running costs of the heat pump to well below that of what gas would have cost. The system was oversized to factor in the installation of a heat pump, if I didn’t get one, payback would be longer.
The EV is leased via company car scheme and taking advantage of the tax breaks. I’ll buy one when that gravy train ends.
For the panels? Nothing just a bit of water and a quick scrub to keep them clean ever few years. DIY or window cleaner job.
It’s unlikely any inverter will last that long, you’ll probably needed to have replaced it once in that period, possibly twice. Call it £600-£1000 per inverter.
Associate
My new costs.
Out of the £319.32 cost for the last year.......... £237.25 are for the Standing charge!!!
Out of the £319.32 cost for the last year.......... £237.25 are for the Standing charge!!!
I think it'd be wise to factor in an inverter replacement every 10 years as they seem to be the most likely component to fail (basic string inverters for those panels are £4-500 at todays prices. South facing with that pitch should not require any other maintenance really.
Soldato
Yeah there is a pretty high chance of inverter starting from year 8 or so.
If its a straight switch and your not an imbecile anyone should be able to do a straight switch of inverter, no need for a spark IMO.
If its a straight switch and your not an imbecile anyone should be able to do a straight switch of inverter, no need for a spark IMO.
Soldato
- Joined
- 23 May 2006
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i got my 1st credit to my account for the free energy period this afternoon... presumably for the 10th september
interestingly (or not), i got a bonus intelligent slot when i plugged the car in, so in effect i assume i was only charged 7p a kwh..... which was why i was only expecting a few pennies back, which is fine, i did it to help the grid and so long as my pay covered the lost couple of kwh of export i would have been happy.
however i got £1.66 so i assume they must have paid me the full rate despite the fact i was in an intelliegent octopus slot.
the last free period (the 14th) i had to bump charge the car, so i sadly wont get 7p electricity for that one.
interestingly (or not), i got a bonus intelligent slot when i plugged the car in, so in effect i assume i was only charged 7p a kwh..... which was why i was only expecting a few pennies back, which is fine, i did it to help the grid and so long as my pay covered the lost couple of kwh of export i would have been happy.
however i got £1.66 so i assume they must have paid me the full rate despite the fact i was in an intelliegent octopus slot.
the last free period (the 14th) i had to bump charge the car, so i sadly wont get 7p electricity for that one.
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@b0rn2sk8 Thanks for the detailed breakdown
. It's an interesting read as I'm looking at taking the plunge myself.
Mind if I ask what sort of house you have? Is it a modern build with good insulation? Did you replace your rads/pipework to work better with your heat pump?
. It's an interesting read as I'm looking at taking the plunge myself.Mind if I ask what sort of house you have? Is it a modern build with good insulation? Did you replace your rads/pipework to work better with your heat pump?
@b0rn2sk8 Thanks for the detailed breakdown
Mind if I ask what sort of house you have? Is it a modern build with good insulation? Did you replace your rads/pipework to work better with your heat pump?
No problem!
It's a 136m2 modern(ish) build from 2003, so not up to modern insulation standards but not terrible either. I've topped the loft insulation up from 100mm to 250 and 300mm (boarded and non-boarded sections) but otherwise its as it was when it was built, including 10mm plastic piping on all of the radiators.
Our hear loss is just under 6kw so we have a 6kw heat pump and a 180L cylinder. 10mm plastic piping is a problem as it limits how much water you can flow through a radiator and therefore caps how much heat I can get out of an individual radiator. Luckily that wasn't an issue for my specific install so no re-piping was needed of any of the radiators other than some small adjustments where a wider one was installed.
That £3500 install cost included swapping most of my radiators, the only ones which were not changed were in the tiny rooms (utility, downstairs loo, en-suit) and the main bathroom which I had previously changed for a larger towel rad. My airing cupboard had to be completely re-piped to install the cylinder and the pipework runs out to the heat pump were new of course.
Insulation levels doesn't really change anything between heat pump and boilers. The lower your insulation levels, the higher your heat loss, the bigger radiators you need and the bigger boiler or heat pump you need. The only requirement for the government grant is that you have no loft insulation recommendations on your EPC. Given how easy and cheap it is to top up your loft insulation to 250mm or 300mm, its a no brainer anyway. Your installer should do a full room by room heat loss survey and determine the required radiator sizes for each room based off the target flow temperature at -2C (for 21C room temp). The actual flow temperature will vary as it will work off weather compensation and will be significantly lower for 355+ days a year where I live.
One thing that people don't realise is that their boilers are probably gargantuan for their their heat loss (30kw is normal) and almost all run at a fixed flow temperature, this massively reduces the efficiency. Condensing boilers advertise >90% efficiency, hardly any run at this efficiency because they are not set up correctly. Like a heat pump, cycling (on, off, on, off, on, off etc) is not your friend and tanks efficiency.
To achieve those levels of efficiency you have to follow the same logic as a heat pump, you need correctly sized radiators for each room, a return temp of 55C or below which usually means a flow temp of no more than 60c at -2C, a weather compensation sensor to automatically reduce the flow temp when its warmer than -2c and minimal zoning (e.g. thermostatic valves). Hardly any installations have this and if the boiler isn't condensing, its in the low 80% range at best. It's also harder to correctly size a combi boiler for heating as you need a huge boiler to get decent hot water flow rates but you seldom need that power for heating. Some really good combi boilers can modulate down to 1-2kw but you still need to do all the steps mentioned above.
The boiler that was ripped out of mine was a Range Powermax 155x, they are not your usual boiler and they don't make them anymore. It was a 100L heat store with an integrated 14kw boiler (old, non-condensing so ~80% efficient). It heated mains pressure hot water via a plate heat exchanger. Other than the poor efficiency (further let down by terrible insulation of the heat store), its capability for a 1 box solution were not bad for its time.
Replacement options in order of price were:
1) a combi but we would sacrifice mains pressure hot water,
2) a heat pump with unvented cylinder
3) a system boiler with an unvented cylinder
We didn't want to sacrifice mains pressure hot water so the combi was struck out immediately and I doubt it would have come in any cheaper anyway as we would have needed to re-pipe the gas supply because it would have been too small. The heat pump was cheaper to install and cheaper to run so it was an easy decision in reality.
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Thanks. That's really helpful. It's good to hear that you're still getting good performance without the perfect setup (small pipes). That's one of my big concerns about heat pumps - thty only work well if you've got an ideal (or close to) setup for them.
The house we're looking at is a similar size, but older with likely worse insulation, we'll be looking to do quite a lot of renovating though. We can easily improve the loft insulation, and any new walls we build will be up to modern standards. We'll likely be moving/replacing the majority of rads/pipework too, so could ensure the replacements are well suited for a heat pump.
The house we're looking at is a similar size, but older with likely worse insulation, we'll be looking to do quite a lot of renovating though. We can easily improve the loft insulation, and any new walls we build will be up to modern standards. We'll likely be moving/replacing the majority of rads/pipework too, so could ensure the replacements are well suited for a heat pump.
That's amazing really as a heavy electric user.
Think our electric bills are about 70ish a month (Inc standing charge)
No EV
Gas hob
Gas central heating
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Anyone managed to get Octopus to refund their surplus credit in their account recently?
The app says I can't do a refund as they haven't had a reading recently. I'm on a smart meter, and I've submitted readings so that's a lie. I've mailed them twice and had no reply.
The app says I can't do a refund as they haven't had a reading recently. I'm on a smart meter, and I've submitted readings so that's a lie. I've mailed them twice and had no reply.
Man of Honour
I have the same message and I'm almost at £1k in credit!!