Batteries for home solar/wind system

Your making the typical mistake that every non tecky person makes when it comes to lead acid batteries be they car type or deep cycle

If you deep cycle a typical car battery 10 to 20 times that will destroy it with whats called sulfation of the plates


If you deep cycle a typical deep cycle battery 100 to 200 times that will destroy it with whats called sulfation of the plates

Now if we take 10% out of a car battery and then recharge it we can expect a ~1000 cycle life

Now if we take 10% out of a deep cyle battery and then recharge it we can expect a ~1000 cycle life


Now we can see that 100 cycles is to low a life time to accept

However to get 1000 cycle life we need ten times as many batteries so we are back to square one roughly

Its when we compare the 20% to 50% discharge capasity of the battery we miight find a suitable ratio that suits the budget

We can expect ~500 cycle life for a deep cycle if we always deep cycle it 50%

We might get ~1000 cycles from a deep cycle if we discharge it 20%

If you go to most good solar power battery sites they will suggest to only take 10% of the capasity out from the batteries deep cycle type lead acid

Now lots of the guys figure that well the car battery is often half the price and can do 10% often just as well so they opt to use car batteries
How that works out I don't know

Really the problem is in terms of power 100KG of battery equals ~1Kgs of petrol

That shows that if 1KG (~1 liter) of fuel costs 1.50 euro and 100 kgs of battery costs probably 2000 euro we start to see battery power is very very expensive
Also it very fragile can short circuit and be wrecked and requires lots of specialist knowlege to use properly lots of maintance and TLC and requires deeeeep pockets

Really if you are going to do batteries then buy a bucket load of them direct from China or USA and save 50% of the cost as even with shipping cost equal to the cost of the batteries ( lead is really heavy crap ) and import tax it will still be much cheaper than buying from local rip off battery suppliers here

When I was in Spain I could buy a 60 Amp car battery in the Carrefour supermarket for 30 euros
Here often it s 120 euros and best prices are maybe 60 euros if you scour Ireland

The deep cycle are even more mad money

It probably still cheaper to go to Spain buy the batteries and ship them out from Spain than buy them here
or even go online and source them from Germany Holland Spain France Italy

Forget the UK they are another rip off SOB


But no matter what price those bandits in ESB charges it still wicked cheap compared to storing power in batteries

Thats why wind and solar power try to hook into the local electric power stations grid
They put power into the elctric grid and gain units and when wind or solar is low they draw the power back from the grid and hopefully they use less than they take out


The only way batteries can be made to half way economic is to try to get hold of the big huge batteries they use in the telecom exchanges

These are huge big banks of these big batteries they use to cover the power failure from ESB and can run the telephone network for several days if the power goes down that long

These are 1/2 ton batteries each one with two volts so you need 6 of them
Even though it big money to get each battery they seem to last for ten years and don't seem to break so easy like the small batteries

Might be able to get them second hand
I think telcoms opertors replace them every 8 years so there is still a fe years left in it

I think they are built from type glass so its bad story if one of them cracks as they got gallons of acid

Might also be issue to have a chemical polution certificate to own and store them in a normal house

But years later they would still be working when you sitting in front of the computer listining to sob stories from other guys why thier 10 batteries of deep cycle all clapped out so soon

sorry lead acid is so fragile and so expensive but the deep cycle sales rep will promise you the sun the moon and the stars and then sub section 5 cluase 3 is the reason why there is no refunds for faulty batteries

good luck with your choises

Derry

For a hobbiest wishing to get longest life cycle ratio the more batteries the better
For a hobbiest wishing to get cheapest cost the less batteries the better

catch 22
very hard to figure the facts without info on the input power from wind and solar

Often shipping costs from France are a lot less than from rip off UK

However if the batteries are in the north of Ireland then driving up and collectting them might be cheaper

Swings and roundabouts

I would just go aound to every car and truck place dumping old batteries and collect as many as you can for free or low costs

When some dont work or some wear out there is no dumping costs as dumps dont charge for batteries

Once you have lots of cheap batteries you can learn how to service them and you can be suprised how many fairly new batteries are dumped

Best sources of info for battery service solutions are the old fashoned ships radio training manuals which needed to service these batterries to send out SOS signals

Then with fact a few years later you can estimate the best solution better


My guess if the wind system is good and proves itself over a few years then going as foot passenger with suitable push cart or bike trailers to carry bateries off the ship or small car to France and buying a whack of the good batteries and comming back would still save you thosands compared to buying in Irealnd

Good quality batterris properly serviced can last sometimes 4 plus years


Also in a few years we might start to see carbon foam lead acid SLA AGB batteries for a good price and being much lighter could be much cheaper to ship than wet lead acid types

How many amps peak and average do you get from the wind power and from the solar power whats the peak and the average???

Derry