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Other Any solar pv/battery ninjas in here?

Discussion in 'General' started by Sentinel-R1, 8 Jul 2024.

  1. Krikkit

    Krikkit All glory to the hypnotoad! Super Moderator

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    Yes it'll be MCS certified
     
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  2. Pookie

    Pookie Illegitimi non carborundum

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    I'm looking to jump on the Solar bandwagon this year too. I have £8-9k to invest so hopefully I can get a semi decent system for that. We are currently paying around £300 per month just on Electric!
     
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  3. wyx087

    wyx087 Multimodder

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    Combined with:
    And the Iran war projected sending gas prices sky rocketing from July.

    I've convinced my parents to get a little plug-in battery + solar setup.

    £824 for Ecoflow Stream Max (1.9 kWh) with 2x 400w panels using ebay's £75 off voucher on ecoflow's official store, inc 10 years warranty.
    + about £100 for CT clamp sensor
    = per day saving of ~50p guaranteed time-shift of 1.8 kWh to EV tariff overnight + whatever the DIY wall hang solar panels can generate.
    = 3-4 years ROI using April 2026 prices, before UK domestic energy prices skyrockets.

    With increasing cost of energy and shipping, I think getting solar + battery quotes in writing as soon as possible would be good idea. Even if you are on the fence. Because I think prices for everything will only go one way for next few years.
     
  4. Spraduke

    Spraduke Lurker

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    I spent ~£6k on a fully fitted 3.2 kWp Solar system about 6-7 years ago and without any major shift in behaviours (apart from turn on dishwasher/washing machine when sunny) I am fairly certain they've paid for themselves and the rest is now "gravy". I discounted batteries at the time as cost was still very high but home batteries are now a fraction of the price. Haven't bitten the bullet yet but the ROI on a battery install is probably similar 5-6 years assuming funded from savings rather than a loan. I would personally avoid taking on debt to fund these kind of things as they are wholly optional and the ROI isn't exactly stellar.

    The best thing to assume is that its a "fun" or "nice" thing to do, and generating your own power gives a fuzzy warm feeling, rather than a purely good financial investment. It isn't a "bad" investment but there are better ways to save/make money.
     
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  5. Pookie

    Pookie Illegitimi non carborundum

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    [​IMG]
     
    Last edited: 2 Apr 2026
  6. IanW

    IanW Grumpy Old Git

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  7. legoman

    legoman breaker of things

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    Not sure how I missed this but I hopped on the solar bandwagon in November,

    14 X JA Solar 450W N-Type Bifacial Double Glass panel
    2 X Hanchu LV 5.12kWh Batteries
    1 X Hanchu HESS-HY-S-3.68K inverter

    Using Octopus outgoing I'm getting good numbers, the Hanchu software integrates with Octopus but the Octopus side is rather meh.
    Seems to focus on pump and dump where I prefer to have grid independence exporting excess to grid. Now the days are longer and we actually get some sunlight it's working well.

    Planning on a 3rd battery going with a 9.4kWh battery as the heatpump munches power in the winter as you would expect.

    Nice example of how its working. On March 21 it was pretty much all day.
    PV output - 17.4kWh
    Fed to grid 11.66kWh
    Consumption 11.01kWh (combined from batteries which had charge from the day before)
    From Grid 0.0kWh

    Currently max generation at any time is slowly rising as the sun is high in the sky

    I am looking at a DIY plug in unit to bolt to the garage roof, the garage is on the same circuit as the house so it will just reduce the load and export the excess as it won't see the battery system. Will be a nice little add in and will only be small two or three panels setup so maybe as much as 1200W.
     
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  8. wyx087

    wyx087 Multimodder

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    Out of interest, what sort of consumption figure are we talking here?

    Say 100 kWh per day gas usage, would that mean 30 kWh electricity usage for heating? So need to be looking at 40 kWh of battery!?

    These panels are heavy! 22 kg for the ecoflow 400w panels I currently have sitting outside. Original plan was to mount it between ground and 1st floor windows, but now I'm not sure it is safely workable just using ladders.
     
  9. legoman

    legoman breaker of things

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    If we take a bad winters day so from the numbers it looks like Jan 5th average outdoor temp was between 0c -3c
    Just for the heatpump
    Energy input = 28.77kWh
    Heat output = 81.7kWh
    COP 2.84

    I can live with around 30kWh daily as I can get the batteries to top up on off peak when the costs are much lower an use that during peak.

    Now that is pre solar, historic weather data shows mainly cloudy so likely very little generation that day. Also its a Monday which means the hot tank goes up to 60c not the normal 50c to nuke any nasties in the hot tank.

    Yeah I know they weigh a fair bit, would be one of those two person jobs for sure! I'd rope someone in for a pack of cold beers probably! I do have a staging which should get me to close to the height of the garage.
     
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  10. Spraduke

    Spraduke Lurker

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    Just looked and I can pick up 10kwh @ 5kwp libbi battery for circa £4k (not installed) which is much cheaper than when I last looked. Sorely tempted.

    I don't think it is cost effective to size a battery to run a heat pump (unless I'm missing something). I looked at my gas usage and in Jan we're probably averaging 100kwh, even at a 4x CoP that is a big ass battery.
     
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  11. wyx087

    wyx087 Multimodder

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    Similar here, ~100 kWh during coldest days. Heat pump efficiency drops as temperature drops, so it's a double whammy for consumption.

    I agree it's not realistic to size battery for heat pump. But I am uniquely positioned having got Indra V2H (vehicl-2-home) kit on my wall, which works with Nissan Leaf to make car battery work like home battery. Our 12 years old first-gen Leaf is getting on a bit. So I am considering 40 kWh or 62 kWh versions. Sounds like more wide spread 40 kWh version will be just about sufficient when combined with 13 kWh house battery.
     
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  12. Pookie

    Pookie Illegitimi non carborundum

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    Just gone ahead with this...

    13 x Aiko Neostar 3S 480W All Black ABC N-Type Mono panels with Fox ESS KH 10kW 1ph Hybrid inverter and 1 x Fox ESS EP12 Plus 11.52kWh Li-ion Battery w/ heating function. Includes MCS, G99 etc

    10K all in including Scaffolding, also throwing in a small EPS with 2 13amp sockets for emergency use. We plan to add another battery and full EPS in the next 18-24 months when funds allow. Edit: we use around 9700Kwh per year!
     
    Last edited: 17 Apr 2026 at 15:44
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