This is a good point , it can work out better value for money to have a slightly smaller solar set up/battery capacity, and just run a geno as and when needed
Help with realistic view
- Thread starter Solardaveo
- Start date
This is a good point , it can work out better value for money to have a slightly smaller solar set up/battery capacity, and just run a geno as and when needed
Solardaveo
New Member
Sorry been away working a more accurate location to where we are meant to be is
- Nearest post code: G83 8SA
- GPS coordinates: 56.0317, -4.50533
Solar panels I found a guy selling them if bought more than 20 pannels the price drops to £109 a 5xx watt or 4xx watt for £100 pv , sounded ok there is a lot on eBay etc too but I’ve seen some can be crap china pannels etc too so learning to see difference would be needed lol
Otherwise I am open to advice
Generator wise I do composting and plan to expand my composter to a biodigester and harvest the gas which using my compressor I can bottle up , so can run lpg generators from that. Also do small scale petrol recycle from plastics etc so can do this as extras just cause I can do why not, also gasifiers seem to be growing in popularity to run generators etc small scale farm in Scotland runs a small unit which pulls home 49kwh a day just below the theeshhold so I plan to play with these too as a fabricator but before I apply these I’d like to make sure I am 100% from a solid source like solar , diesel gen on red d lpg generator
Also if I have running water and I can make enough drop from I will harness that too which can drop the need for solar at all but until march we wont know what woodland we lock down or what it has , so for that solar will be in my lorry to guarantee my power .
I plant to fill my lorry with everything we need and go set up solar /water /toilets etc and get on generator will carry my workload till solar is active so need to work out a system I can start buying that will work
All sound very exciting, keep us updated
Yea it's a good price, just about as cheap as you can get them right now
That's the important part !
Do let us know if/when you get that working , I would be very very interested
Will it get cold where the batteries are going to live? If so your best option are AGM batteries, they are much more suitable for use in cold conditions
Sorry to spam your post ?
Dagoth Ur Does Solar
Solar Enthusiast
I would suggest just taking a look at the modern state of lithium batteries- Lithium iron phosphate batteries aren't subject to the extreme runaways fires that get reported on in the news. Those are virtually always some lithium iron chemistry with cobalt in them.
You have some requirements such as not charging the batteries if they are at freezing temperatures, but really, the cost to kWh ratio is just miles above anything else. Not to mention the amount of cycles LFP batteries can take compared to lead acid.
Not saying to jump on LFP blindly, but I'd really be taking a hard look at them.
Aridom82
Learning addict
So for your location PVGIS spits the following:
For 24Kwp panels, 70º inclined, oriented to South, assuming 93% efficiency
Jan 603kwh
Feb 1137kwh
Mar 1729 kwh
Apr 2332 kwh
May 2441 kwh
Jun 2146 kwh
Jul 2190 kwh
Aug 2046 kwh
Sep 1711 kwh
Oct 1312 kwh
Nov 897 kwh
Dec 564 kwh
December is again the lowest production month, with 564 kwh, or 18,2 kwh a day on average.
May the highest production month, with 2441 kwh, or 81,3 kwh a day on average.
Let me know if you want the data for other inclination/orientation.
Solardaveo
New Member
wow that seems like alot of electric lol, i didnt expect that? am i see right that evenin december 564 by 30 gives 9.8kwh of electric ? and it only drops really for 3 months then is back up to above my 12kwh useage ? am i reading that right ?
if so how does all the surplus summer power being that 2441 would be 80kwh aday ? will all that go in the battery useable in the year where december etc falls right ?
if that correct would a 12kwh system do half that but stil averages out to giving over 12kwh aday ??
what batteries woudl be needed being that 12kwh aday is used do i really need a 48kwh system on a 24kwh array if most will be used and only stored to use in winter ?
il be back in the morning im really tired from work if this needs translating i am sorry lol
hwy17
Anti-Solar Enthusiast
Surplus that the batteries or charge controller can't absorb gets left on the panels and turns into heat.
Aridom82
Learning addict
No, 564 kwh produced in the month divided by 31 days is 18,2 kwh a day. 6,2 kwh more than your 12kwh daily estimate
I wish this was correct but it is not. There is not a battery big enough to hold all the power produced in the summer so you can use it in the winter.
For a 24kw system i would recommend a battery in the 60-90 kwh range. That can hold only the power produced 1 day in the summer.
The idea of having a battery is just to have energy for when the sky is cloudy for days. When the sky is cloudy the energy production is very low. For example if during the winter there is lets say 5 days when the sky is cloudy you would not have any power interruption with a 60kwh battery if your daily consumption is 12kwh. 12kwh of daily consumption multiplied by 5 days is 60kwh.
I have a system with 16kwp of panels and a 60kwh battery in my house. Now is late autumn and i heat my house using the power my system produces. But everyday is not the same weather. There are sunny days and cloudy dark days. With my batteries, even if there are 3 days in a row where the weather is clouded and my panels produce very little i am still using the energy accumulated in the batteries. And when there is a sunny day again, the panels produce a lot and charge the batteries at full again.
I hope i explained well, let me know if you have any doubts.
One issue with december production is if the loads are during the day, it will absorb the energy, and not feed the battery to recover.
It depends on where the 12kWh is in the day.
Solardaveo
New Member
thats awsome
thanks, haha so i under calculated my mother thats not a bad thing so you heat using electric ? if you dont mind me asking how come you dont use a log burner or such ? , you have a 16kw solar system thats like 40 400w panels right ?. and a 60kw battery bank do you use deep cycle or li for the batteries ? im guessing deep cycle with over double ?are you in the uk sun light too ? , so are you saying based on your system in winter you dont even need to use a generator to get power ? cause the amount of panels you have is able to exceed your usage on a sunny day ? whats your daily use kwh ? is it less than my -12-15kwh a day can you share your stat graph at all lol if i am not too cheeky i wish we could all talk in person there is somuch to ask haha i know location wise that our systems woulr differ but its a really cool comparison eh and learning ,
wondering if like you i could save say 8kw of solar pannels (24 to 16kw) and use that money on more batteries would be a better option and based of them stats further up it over produces on a 24kw system right
somthing like this i guess
fleabay batteries
so i dont like li batteries but there said to be so expensive cant people use thses ? ive seen a vid someone uses his ev to power his house so cant this just ourtright be used ? ev battery
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Aridom82
Learning addict
Yes i heat my 170 square meter appartment with two mitsubishi kirigamine air conditioning units (they do heating too), and i also have two wood pellet stoves installed but these days i rarely use them. When the war in ukraine made the price of gas and pellet skyrocket just before the winter one year ago i had to pay a lot for my heating so i decided to put my money to better use and transition to solar energy.thats awsome
Yes i have exactly 16,43 kwp or 31 panels 530 watts each. I use Lifepo4 batteries. I am not very familiar with the deep cycle ones.
Aridom82
Learning addict
I am in north Italy. With my system i dont need to use the grid power or a generator most of the time. My solar production exceeds my daily usage but i dont mind having an oversized system because i keep finding new things in which to use my energy.
Now that i am heating the appartment with electricity i use around 20-25 kwh a day in total. 15kwh for heating and the rest for the utilities (lights, cooking, hot water, freezer, computers...)
In a sunny day in November my 16,43kwp of panels produce around 50 kwh.
Aridom82
Learning addict
According to the same calculator, a 16 kwp system on your location will produce around 12,1 kwh a day in December on average, the lowest production month.
I myself like to oversize the system a bit. In your situation i would go for a 20kwp system.
Unfortunately i am not familiar with these type of batteries, i only have lithium.
There is a section on this forum dedicated to batteries, if you post a question on it i am sure you will find somebody that knows more than me about it.
Reality check: between your low winter sun angle, overcast skies, and snowfall? Is that even feasible at any price?
I suspect there's not much solar up there. When you drive around the neighborhood do you see many panels? What do the locals think/do?
I suspect there's not much solar up there. When you drive around the neighborhood do you see many panels? What do the locals think/do?
Solardaveo
New Member
Every 5th house has panels most range from 4 to 12 but I believe they stil use the grid
Some farms and bigger houses have up to 30 panels but yes a lot do have them here we even have solar farms on field using over 500 giant pan els
Be aware of 'averages'. Today (being dull and rainy) in sunny East Anglia, I got 1.5kWh from 6.6kWp of panels. This time of year is not good without grid backup and/or sizeable batteries - preferably both.
Solardaveo
New Member
when we talk sizeable batteries i read that we cant store more than 5 days electric without havign to use it ? so if thats true what good would more batteries do ? my origional though was that more meant more storage from summer for winter, but i learn that apparently not true, ?
thus i will be getting 16kwh id have almost 5 from your count eh , have you looked at angles? you can make an adustable angle frame for the pannels if ground mounted which help ALOT , when in winter you can change the pannels angle and double the gain well adjustment monthly
grid wont be avalible to me which is why i plan to use my gas generator from my gas or my petrol from my byproducts , etc unless i have running stream then im golden, but yeah backups i will have but not in means of grid ,
Not true. Don't believe everything you read on the Internet
I was feeling very smug the first time I used my batteries, knowing that I was using up Chinese electricity from several month beforehand Here are some real life figures from last December - this is for East Anglia too = much further south than Scotland.
From 6.6kWp panels...
- Worst day (early December 2022) = 0.4kWh. Yep zero point 4
Several other days were around the 1kWh mark.- Worst week (early December 2022) = 17.4kWh.
So, if you have 24kWh of panels, you'll be looking at best 4 times that amount = worst day 1.6kWh, worst week 70kWh, give or take a bit.
Of course. But that is largely irrelevant when it's very cloudy - luminescence is not very directional at all when it's dark clouds and rain.
HTH.
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