New, and have i got the right forum?

thinking about it, i think i might grab myself, 2 45Ah batterys, will add up to 72hours overal, and can alternate them, charge one for 1 day, and swap them every other day
can get 2 for around £50 i think from new from halfords
or free from scrappy, but might be best new, will last longer
so £50+£80+£50 = £180
for the panel, 2 battery's and the tunnel. Now i need to some how support this, make the all teh wood frames and the pvc with £220

How much do you think the wood will cost??

Thanks
Mike

 

does anyone know how long it will take to charge a 75Ah battery?, theres some for £45, but if i bought 1, it would mean the pump would be turned of for a little while, when i charge the battery?

 

It depends on the charger. A few hours max.

There's no need to cut power to the pumps if you have two batteries. Connect the batteries in parallel and then you can just remove one to take away to charge up, while the other remains in the circuit.

I.e. On the 2 batteries, connect the 2 positive terminals together, and the 2 negative terminals together. That becomes one bigger battery. Then when you take one off, the other is still providing power.

 

Thanks, i shall do that, i'll hed to the scrappy this weekend , to see if they have a a couple

But is it risky taking one out of a van? also should it say what V and Ah it is on teh battery?

 

Hello Michael, only just seen this and I wish you luck. I would like to add my 2p worth.
You say you want to pump around 500 LPH, to what height?
The reason is, that in order to make a pump sound better the makers will quote flow rates at 0 head. All pumps have a pump curve but you hardly see one for solar pumps as they are so small. Below is a simple pump curve.



Across the bottom is Litres per minute and up the left is height in metres. You read it by going up the side and across the bottom until you meet the darker line.

example. Look at the 200, follow it up, now look to the left, it hits the dark line just under 2m.

so that means this pump can pump 200 litres / minute to just under 2m in height.

now look at the 300, follow it up and again look to the left it indicates around 50 cm

now look at 4m (on the left and follow it across) it hits the dark line at 30 Lpm

so you now know that at 4m in height this pump will only pump 30 litres / minute.

I know you don't want that much water to be pumped, it was just an example of a pump curve and how to read one.
Now back to your pump, the 500 LPH is very likely to be the pumps maximum flow, so if you are pumping the water more than a few cm you will probably need a bigger pump to be sure.

Most solar pumps are not designed to run 24/7 if you do run it 24/7 it will not last that long, but I hope I am wrong.

As you will be running the batteries flat all the time, you should use leisure batteries, NOT car batteries. But for comparison.....

Just looked at halfords (other suppliers of car batteries are available)

found this:
Specification

• Guarantee: 4 Years
• Startup Power: 440 Amps
• Type: Calcium
• AH Value: 44
• Bench Charge: 4.4 Amps
• Dimensions (LxDxH): 207x175x175mm
• Reserve capacity: 80
• Weight (kg): 11.68

It costs £77 and needs 4.4 amps to charge it. (halfords item number 950303-0)
AND its only 44AH

Found this leisure battery.

Voltage: 12 Volts
Capacity: 90 Ah
CCA: 1000 A
Length: 258 mm
Width: 171 mm
Height: 220 mm
Cust. Rating:
Guarantee: 4 Years





Price
£79.95 inc. VAT
Standard Delivery
£7.98 inc. VAT

Call it £88, you still need two.


I found this article for you.

Leisure batteries and car battery's - what's the difference??

A car battery is designed to give out a large amount of power in a short space of time (starting the car) and then being quickly recharged. A leisure battery on the other hand is designed to store power and release it over a much longer period of time. Undoubtedly you can use a car battery in your caravan but it is unlikely to work very well in the long term.

Taken from HERE


In (my) conclusion:

Solar panels need a lot of bright sunshine to work to their given output, yesterday it rained most of the day.
Taking it that you need at least 5 amps to charge the battery, then lets say 2 Amps for the pump (total of 7 amps) You will need a solar panel that can supply at least 84 watts. As its not bright all the time, you will still need 7 amps, so the best option is two solar panels each at minimum of 80 watts. You also need a regulator.

I am not saying it can not be done, I am saying its going to be more costly than it first looks.

I really admire what you are trying to do, I would suggest you check out some more options. / Calculations.

Best wishes.

You may also like to try your own research on the following:

Deep cycle battery
Solar regulator
Solar panel out put
Tank / water ratio for fish
Solar pumps
12v pumps

 

Thanks alot,

Wow, a very big write up and a great read. This as completely changed my mind and view on how its going to work now then and i think after your reply i will have to rethink the whole solar system, because i have realised its going to cost me £320 just to pump a 13w pump 24/7, which is simply crazy! and this still means id have to charge them off the mains anyway, so im going to look for a new option, see if wind power is more suitable, and how much it will cost me :L,
The pump will have to reach about 8ft ( 2.5 meters) and pump around 1220Lph, so im going to have to look for a huge pump!, might also have to go back to the dutch idea, with the rack, and use my house electricity, although i did want it outside tbh :L

Thanks
Mike