Andrew Croft wrote: ↑Wed Oct 18 2017 19:25 -
Thanks duncan. Do you reckon this would be easier to rig up than the turbine with similar results in output?. I do like the idea of bodging together a turbine though.
So go with a 20a regulator like the ones earlier in the topic then?. 30a would be better wouldnt it(future proofing) ? Am i right in thinking a higher amperage charge controller wont degrade the output of say one more suited to a 10 or 20 amp charge controller
I love electronics and tinkering but its a ballache to understand and retain. Ive electrocuted myself more times than id care to remember
Had to go and get the laptop for this one as too long to do on the phone.
When sizing, always choose a component that's at least 25% higher than the calculated peak power.
The turbine will certainly be more of a challenge to set up and I would take the opportunity, very few people have a chance to rig one up as they don't have access to the right type of water, where as almost everybody can set up a solar system
Watt for Watt, the turbine will give you more available power as it will run 24 hours a day, in the winter the turbine will give around 10 times the power of the solar.
Its relatively easy to work out what your solar output is likely to be. If we assume that the peak is 150Wp based on facing south panel for a G1 postcode, you can expect the following power per day ON AVERAGE.
Jan 15 Ahr
Feb 20 Ahr
Mar 27 Ahr
Apr 36 Ahr
May 41 Ahr
Jun 40 Ahr
Jul 40 Ahr
Aug 39 Ahr
Sept 32 Ahr
Oct 24 Ahr
Nov 18 Ahr
Dec 12 Ahr
For the turbine is a bit more complicated, if you went for a 10W turbine, assuming it had enough flow to run at 80% output 24 hours a day, =8/12 = 0.666 Amps*24hrs = 16 Ahrs per day. Assume around 10% losses (which is already in the solar calc) so around 14 Ahrs day.
a 150W Solar panel would give you around 10000 Ahrs a year, whereas the turbine about 5000 Ahrs, but December will be the limiting factor for solar.
Now how many Ahrs you need per day is the big question, that is always the tricky bit with working out how much power is needed, in fact its several questions.
What is the power and time of use of the appliances?
What is the usable storage capacity?
How long is the recharge period.
Lets say 100 watts for 5 hours per day with 24 hours between recharge periods.
100 watts/ 12 volts = 8.33 Amps x 5 hours = 41.7 amps.
For practical purposes, usable storage capacity is battery capacity/2 , so 50 Ahrs.
So you know that the required power is less than the capacity, so that's ok, but you have to generate 41.7ah in 24 hours to recharge, the solar panel would just about cut it in the summer, but has no hope of keeping up in the winter, the turbine not at all.
If the period between uses was 72 hours, you only need 41.7/3 = 14 Ahr/day, so the turbine would be fine and the solar ok apart from December.
You can replace the numbers above with what you think will happen to your system, if its daily use I would factor in a 50% margin on the solar to cover s**t days.
Go turbine, maybe buy one of those off ebay, get the rest of the electronics right and then see if you can build your own turbine
We are spring cleaning our warehouse over then next week or so, I will see if I can find anything useful for you.
China indeed.
