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Random Renewables Thread

1…8283858788…97

Comments

  • #2522
    SD_DRACULA
    Registered Users, Registered Users 2 Posts: 2,722 ✭✭✭SD_DRACULA


    For the people using lifepo4 wrong and living in fear of degradation

    https://www.youtube.com/watch?v=UbZiHzflKMY

    Always go from 0% to 100% basically because no matter what you do they will lose capacity due to calendar aging anyway so you're just wasting money going between 20 to 80%



  • #2523
    deezell
    Registered Users, Registered Users 2, Paid Member Posts: 8,396 ✭✭✭deezell


    https://www.boards.ie/discussion/comment/122829861#Comment_122829861

    The last 10-15% is more inefficient to charge, you'll put in significantly more kwh than you'll get out, so if you're charging off the grid, then back to FIT in daytime or self use, you're saving very little on that top kwh of a 5kwh battery, just ageing it quicker with heat.



  • #2524
    SD_DRACULA
    Registered Users, Registered Users 2 Posts: 2,722 ✭✭✭SD_DRACULA


    https://www.boards.ie/discussion/comment/122829923#Comment_122829923

    Heat is nothing when charging with a PV inverter (especially in Ireland), batteries work best at 21c too, watch the video 😉

    But this is more for people with big DIY banks not 5kw pylontechs, 10% there makes no difference either way



  • #2525
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122829923#Comment_122829923

    Tell me without telling me you have no experience with LFP batteries, There's nothing correct about that statement 😂.

    The AC/DC conversion loss is constant.

    At the charge rates, LFP don't get warm.

    Charge rates do slow near the top but with LFP it's really only when the batteries are 99% full (due to the voltage charge curve of LFP) so even when it does slow down to high state of charge.. the amount of power it uses to charge also reduces.



  • #2526
    deezell
    Registered Users, Registered Users 2, Paid Member Posts: 8,396 ✭✭✭deezell


    https://www.boards.ie/discussion/comment/122830186#Comment_122830186

    I suppose tesla are wrong then to suggest 80%. Sure what would they know.



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  • #2527
    slave1
    Moderators, Sports Moderators Posts: 18,817 Mod ✭✭✭✭slave1


    https://www.boards.ie/discussion/comment/122830410#Comment_122830410

    Tesla say 100% on their LFP battery pack, its the Lit Ion packs that they suggest 80% for normal day to day.

    Tesla know their stuff

    My stuff on Adverts, mostly Tesla Pre Highland Model 3

    Public Profile active ads for slave1



  • #2528
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122830410#Comment_122830410
    https://www.boards.ie/discussion/comment/122830540#Comment_122830540

    My point exactly. The 80% on Li-Ion is for battery life and prevention of degradation. Not that charging 80-100% is more inefficient or somehow just burns power. Just charges slower.



  • #2529
    deezell
    Registered Users, Registered Users 2, Paid Member Posts: 8,396 ✭✭✭deezell


    https://www.boards.ie/discussion/comment/122830756#Comment_122830756

    Very much slower, so the overhead of the BMS system is higher in relation to the trickle power bring inserted into the cells, and even if the energy transfer of this voltage sensitive charge phase was as efficient as the mid constant current phase, it's not ideal to have a power shifting device effectively out of service on a trickle charge, when it could be pushing it back out as FIT.

    I wonder why so many mobile phone batteries die after a few short years, despite having abundant processing power to micro tune the last trickle stage of charging? It all depends on how cautious the BMS are in the final fifth. Perhaps more years of evidence needed before we can definitively say that actual100% is good for your cells in the long term. I say actual to distinguish the practice of manufacturers underrating their cells to give them some headroom for protection, which is a good idea in any engineering field.



  • #2530
    bullit_dodger
    Registered Users, Registered Users 2 Posts: 2,753 ✭✭✭bullit_dodger


    https://www.boards.ie/discussion/comment/122831019#Comment_122831019

    it's not really fair though to compare the two (mobile phones and house batteries). Different chemistries and as a result different charging power curves. Lithium batteries, as in the ones in your phones don't really like being at 100% and constantly being charged to 100%. Your dead right - constantly charging these guys to 100% over time degrades them.

    I noticed on my S23 (a year old now) that Samsumg have a feature where they allow the user to "protect" the battery and prolong it's life by setting max change to 80%. I use this myself for day to day use, and if ever I think I'm going to need the full charge like travelling on a plane etc, I set it to go to 100%.

    House batteries though (at least the LiFePo ones) don't suffer the same way. You can "have at it" to 100% all the time without fear of degragation. I wouldn't personally store them at 100% for months on end if your not using them, but no massive downside to charging LiFePo batteries to 100%. I would not go under 5-10% though, that CAN cause issue, but you should have 90% of your battery usable.

    Good video explain the usage cases is….

    Green Friday CE IE wide



  • #2531
    SD_DRACULA
    Registered Users, Registered Users 2 Posts: 2,722 ✭✭✭SD_DRACULA


    https://www.boards.ie/discussion/comment/122831365#Comment_122831365

    If you go to 0% and more or less immediately charge them back up is fine, just not good if they stay there for too long.

    But yeah 5-10% is a good stopping point, gives you a bit of a buffer in case of an outage, you can make a few cups of tea 😂



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  • #2532
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122831019#Comment_122831019

    This current discussion is about Lithium Iron Phosphate batteries.

    A battery management system BMS, doesn't physically control the charge. It's power requirement is static. And tiny. It only steps in if something is going wrong and disconnects the battery.

    It may tell the charger/inverter what it wants though. So theres no extra power use from that end.

    As for the charger inverter end, I'm measuring about a 8% loss from AC into the inverter and DC into the battery. Might try taking my inverter off grid and see if I can measure the DC DC loss sometime.

    It didn't matter if I was charging at full speed or topping off the battery at 99.5% the power in Vs power out loss is about the same.

    As for pushing it out for FIT, the inverter can trickle charge the battery and export AC at the same time, it's not an either or situation.

    New phones. Well that's a different story… they were live fast die young, new phone please.

    Could be changing, my pixel 7 is 2 and a bit yrs and battery is currently fine Vs my previous phone when it was 2 yrs. This one does have adaptive charging, so it charges slower etc.

    That's actually another point solar batteries rarely reach 0.5c charge rate, phones on a fast charger, assuming a 2000mAh battery at 45W is something like 6c.



  • #2533
    DC999
    Registered Users, Registered Users 2 Posts: 1,633 ✭✭✭DC999


    That time of year again to look at energy usage. We've reduced 2500kWh of gas heating per year by adding 2 small electric rads (over the last 2 winters). I did that intentionally to reduce the amount of gas we use. It's a 20 year old boiler that started with 79% efficiency. Whose guess as to how low that is now.

    The rooms the electric rads are in a much more comfortable and stay at the exact temp we want.

    Ok, small house and we don't mind lower temps than most. And it's a poor BER, which we're slowly working on improving for this heating season. And of course we're not saving energy (well, we are on the gas boiler that is likely 60% off efficient V electric rads), more substituting some gas for some electric heating.

    Dream would be DIY heatpump hence the fluting around to see what we're need. But that's down the list of other household jobs to do



  • #2534
    Victor
    Registered Users, Registered Users 2 Posts: 78,904 ✭✭✭✭Victor


    Folks, it isn't LiFePo, it's LiFePO4.

    The difference is whether you die of radiation poisoning or not.



  • #2535
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122838455#Comment_122838455

    Po is alpha decay, you'll be fine unless you're eating the batteries!



  • #2536
    [Deleted User]
    Posts: 2,768 ✭✭✭ [Deleted User]


    Pfizer Ringaskiddy are working on a large Pv system on car park canopies. I've no details as I only saw them working on it today, they were fitting the panels in the piddling rain.



  • #2537
    con747
    Registered Users, Registered Users 2, Paid Member Posts: 10,919 ✭✭✭✭con747


    A large ground system just outside of Kinnegad.

    image.png

    Don't expect anything from life, just be grateful to be alive.

    Help Keep Boards.ie Alive sign up here

    https://subscriptions.boards.ie/ Keep Boards Subscribed To.



  • #2538
    mjatkey
    Registered Users, Registered Users 2, Paid Member Posts: 442 ✭✭mjatkey


    Guys, I'm telling you there is money to be made in this solar idea!? Plus of course saving the planet.

    🌞 6.96kWp PV System. West Dublin🌞



  • #2539
    Ubbquittious
    Registered Users, Registered Users 2 Posts: 6,370 ✭✭✭Ubbquittious


    The amount of commecial solar farms going up these days is insane and I reckon they are downplaying or not really drawing attention to it because it means a rugpull for domestic solar systems is nearly upon us



  • #2540
    conor_mc
    Registered Users, Registered Users 2 Posts: 832 ✭✭✭conor_mc


    If you look at the UK, it’s more likely that farmers get up in arms over “good agricultural land” and nimby’s over their pristine views being destroyed. Plus, it’s really only a drop in the ocean and not much to write home about if we’re being really honest with ourselves.



  • #2541
    deezell
    Registered Users, Registered Users 2, Paid Member Posts: 8,396 ✭✭✭deezell


    Massive solarfarm built 5km from me went in without a mention, poor bog land, the sheep can still graze under it. What's to complain about. (There was ructions though about the windmills originally planned).

    Google image not fully up to date.

    Screenshot_20241119_092507_Maps.jpg


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  • #2542
    Victor
    Registered Users, Registered Users 2 Posts: 78,904 ✭✭✭✭Victor


    That's Hortland Solar Farm: https://www.openstreetmap.org/way/1127876123



  • #2543
    deezell
    Registered Users, Registered Users 2, Paid Member Posts: 8,396 ✭✭✭deezell


    What's the capacity on sunny day I wonder? The only nimby issue they had was being forced to run the 3 phase HT underground on the public road for several km to get to the HT grid. Complete nonsense and must have cost a fortune.



  • #2544
    the_amazing_raisin
    Registered Users, Registered Users 2, Paid Member Posts: 13,566 ✭✭✭✭the_amazing_raisin


    One interesting thought I have is how the passive income from solar compares to the profit (not income) from farming

    Let's say for example I have 100 acres. Apparently you can get over €1000 per acre per year from solar farms, and it's indexed linked so grows with inflation every year for 20 years or something

    I've no doubt that you can make more income by farming the land, but the costs are also greater plus you have to actually do some work

    So in that context €100k of passive income for sitting on my arse all day does seem pretty attractive. I could have a small hobby farm or do some other work to supplement my income, and I probably wouldn't be up at 5am every day doing back-breaking labour

    "The internet never fails to misremember" - Sebastian Ruiz, aka Frost



  • #2545
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122858075#Comment_122858075

    €1000/acre. You won't be making that by farming.

    Easy counting example, good tillage land, you put in winter barley, that could yield up to 4t/acre

    Barley off the combine this year is coming in at 210, possibly a bit more if you go for the malting... That's not even €900/acre.

    You still have to pay for seed, fertiliser(4t/ha has to be fed well), sprays and also the work (ploughing, seeding, fert spreading, spraying, harvesting).

    If leasing land for farming, your chatting €100-200/acre/year and the margins are tight on that if you are looking for any profit.



  • #2546
    Cyrus
    Registered Users, Registered Users 2 Posts: 22,057 ✭✭✭✭Cyrus


    https://www.boards.ie/discussion/comment/122858075#Comment_122858075

    not quite that simple though, they need to get a fully permitted project with access to grid, so really depends on how buildable a project is on your land, how far you are from a substation and what kind of grid offer they can get. all that can take years.



  • #2547
    the_amazing_raisin
    Registered Users, Registered Users 2, Paid Member Posts: 13,566 ✭✭✭✭the_amazing_raisin


    https://www.boards.ie/discussion/comment/122858228#Comment_122858228

    True, there's only a few places that are suitable and it isn't like you sign the dotted line and get your money straight away

    Still, it's easy to see the selling point

    https://www.boards.ie/discussion/comment/122858182#Comment_122858182

    This is kind of what I suspected. I'm guessing grazing makes more money but is still competitive (insights from the idiot jackeen 😂)

    I think this is kind of a byproduct of the world we live in. We're a high tech economy where agriculture is one of the biggest employers

    Food is also comparatively cheap and the powers that be want to keep it that way. Understandable since if you ever want to create civil unrest really quickly just make food expensive and scarce

    So in that environment, farming becomes a high labour/high cost/low margin industry largely kept going by subsidies

    I'm very happy with the idea of subsidies since I think domestic food production is very important, but it'll still be a low margin business

    If that's the case, then it's very easy to see farmers jumping on some passive income while also reducing their workload and costs

    "The internet never fails to misremember" - Sebastian Ruiz, aka Frost



  • #2548
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122858617#Comment_122858617

    Grazing not much better unless you can get dairy cows near it. Although grazing is the cheapest way to feed livestock,

    Although if grazing under panels, you better make sure there is no cables and the likes accessible to the sheep. They will chew on them if they can get at them.

    As mainly a livestock farmer myself. (we do a bit of barley but only feed grade). A lot of carbon reducing things are to reduce meat. I look at my enterprise, and the only thing we can do well is grow grass. Cereals, for human consumption isn't an option. If no sheep or cattle, Bio digesters seem like the only avenue, But even there is land that we can graze easily, but to wouldnt want to put the machinery over it to cut the grass.



  • #2549
    DC999
    Registered Users, Registered Users 2 Posts: 1,633 ✭✭✭DC999


    https://www.boards.ie/discussion/comment/122859298#Comment_122859298

    On a slightly similar theme, Octopus are building sheds for farmers and Octopus then 'own, the energy created. Farmer has space and a need for storage. OK, it's not large scale solar but interesting idea.

    https://theprogressplaybook.com/2024/08/13/win-win-octopus-energy-will-give-free-solar-covered-storage-sheds-to-french-farmers/



  • #2550
    graememk
    Moderators, Home & Garden Moderators Posts: 7,546 Mod ✭✭✭✭graememk


    https://www.boards.ie/discussion/comment/122861058#Comment_122861058

    More power than you think

    image.png

    blurry, but thats a 3 bay shed, The one in the article show a 7 bay. That is 7.2kwp on the roof, If it was done now it would be pushing 10 for the same size. And I could fit at least the same amount on that one. so 20kW on 3, on a 7 bay, easily 50kW Even more if it was designed to fit solar, (eg 3 rows instead of 2)

    Would not say no to a free shed, I think a lot are used for hay and straw storage.



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  • #2551
    the_amazing_raisin
    Registered Users, Registered Users 2, Paid Member Posts: 13,566 ✭✭✭✭the_amazing_raisin


    Next thread will be @graememk installing 200kWp of ground mounted solar and going for an NC8 connection, then living a life of luxury off the proceeds 😁

    "The internet never fails to misremember" - Sebastian Ruiz, aka Frost



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