Power!

[pyemaster]

Likewise! Thanks for the link, watts are beyond my limits of comprehension right now, I'm only just remembering amps!

I've been thinking I needed to work out amp draw to calculate amp hours?! This is bloody confusing...

Owen

[Growler]

Likewise! Thanks for the link, watts are beyond my limits of comprehension right now, I'm only just remembering amps!

I've been thinking I needed to work out amp draw to calculate amp hours?! This is bloody confusing...

Owen

try THIS

[pyemaster]

That's brilliant!

So, if a tablet/phone draws 2 amps, two 20W LED lights 4 amps and a portable speaker 1 amp (7 amps in total), this total multiplied by 12V (because it's a 12V battery) equals 84W. This, multiplied by 6 hours (maximum time used per evening) amounts to 504 watt hours?

So this would take a 120w solar panel 4.2 hours to charge this amount? Can it be as simple as that or am I totally way out / missing something

Owen

[pyemaster]

Okay fellas, for those interested in maybe sorting out a similar solar setup, after exhaustive research this is how I'll be doing mine:

Power calculations...


Smartphone

2600mAh battery, 5v charge = 13wh

Tablet

4450mAh, 5v charge = 22wh

Bluetooth speaker

2200mAh, 3.6v charge = 8wh

LED light

18w (for four hours of use) = 72wh

So...

Scenario a) Total charging phone / light / speaker = 93wh

Scenario b) Total charging tablet / light / speaker = 102wh

Scenario c) Total charging phone / tablet / light / speaker = 115wh

Considering I'll probably be using the solar panel for camping mainly in three seasons (March - October) and mainly in West Wales, the irradiance figures for Swansea (for a 100w solar panel operating at 75% efficiency to account for losses in the system and capture process) are:

February - 100kWh/Sq m
March - 166
April - 264
May - 342
June - 356
July - 353
August - 298
September - 203
October - 116

With these as an average then, a 100w panel should be able to provide enough power for all my items in 8 of 9 months, and enough for lighting, speaker and phone or tablet for February.

November, December and January provide 67, 44 and 54kWh/Sq m respectively, which is still enough for a couple of hours of lighting and a fully charged phone.

The above is also calculated for 'worst case', i.e. in powering each item to full charge each day. Realistically the only thing needing daily charge would be the light, the other items could be charged every other day, as they are each supposed to last at least 10 hours once charged.

I've also measured the roof space behind my roofrack, which is 100cm x 80cm. A 100W panel fits perfectly in this space, and I'll fit it on a hinge and catch to angle it perpendicularly to the sun ray angle when in camp. I could now go on about MPPT controllers but I'll leave it at that.

Hope this helps someone!
Owen

[budweiser]

use wind power, forget the solar panels

[AlexKzn130]

Okay fellas, for those interested in maybe sorting out a similar solar setup, after exhaustive research this is how I'll be doing mine:

Power calculations...


Smartphone

2600mAh battery, 5v charge = 13wh

Tablet

4450mAh, 5v charge = 22wh

Bluetooth speaker

2200mAh, 3.6v charge = 8wh

LED light

18w (for four hours of use) = 72wh

So...

Scenario a) Total charging phone / light / speaker = 93wh

Scenario b) Total charging tablet / light / speaker = 102wh

Scenario c) Total charging phone / tablet / light / speaker = 115wh

Considering I'll probably be using the solar panel for camping mainly in three seasons (March - October) and mainly in West Wales, the irradiance figures for Swansea (for a 100w solar panel operating at 75% efficiency to account for losses in the system and capture process) are:

February - 100kWh/Sq m
March - 166
April - 264
May - 342
June - 356
July - 353
August - 298
September - 203
October - 116

With these as an average then, a 100w panel should be able to provide enough power for all my items in 8 of 9 months, and enough for lighting, speaker and phone or tablet for February.

November, December and January provide 67, 44 and 54kWh/Sq m respectively, which is still enough for a couple of hours of lighting and a fully charged phone.

The above is also calculated for 'worst case', i.e. in powering each item to full charge each day. Realistically the only thing needing daily charge would be the light, the other items could be charged every other day, as they are each supposed to last at least 10 hours once charged.

I've also measured the roof space behind my roofrack, which is 100cm x 80cm. A 100W panel fits perfectly in this space, and I'll fit it on a hinge and catch to angle it perpendicularly to the sun ray angle when in camp. I could now go on about MPPT controllers but I'll leave it at that.

Hope this helps someone!
Owen

Wow it's a lot more thorough than wat I figured out, well done mate, I'll use ur post as a point of reference

[budweiser]

it is very good, i was thinking to do something similar on the 3l

[LClark007]

Thanks for such good information. I'd considered that a solar panel trickle charges the main batteries, I wonder if it could be used to charge a portable battery pack in the same way. I need this for my work. I reckon a decent jump pack would do you. If I am a technician, all my tools are in my car all the time and I have everything when someone calls me. I had an old solar generation that helped to get rid of some troubles for many years and now I want to buy a new one. I hope that I helped you.

[Leo Stolenberg]

Hi! Well, this is a pretty interesting solution, I have a similar situation