Solar led strip lights on steps?

[Mammoth]

Hi
I need help working out what size battery and panel I need to light up the steps to my spa,
I have built a box with the solar charge controler and a photosensor on/off switch. I plan on running a 5m length of led's totalling 24w. I am averaging the on time of 10 hours 24w/12v*10hr =20ah I think?
Should I need a 40ah+ battery and what size panel to keep it topped up each day.

[SunEagle]

Hi
I need help working out what size battery and panel I need to light up the steps to my spa,
I have built a box with the solar charge controler and a photosensor on/off switch. I plan on running a 5m length of led's totalling 24w. I am averaging the on time of 10 hours 24w/12v*10hr =20ah I think?
Should I need a 40ah+ battery and what size panel to keep it topped up each day.

First off you shouldn't discharge your battery more than 25%. So I would up size that battery to 75Ah min but 100Ah is better.

Next depending on where you live and how much "usable" sunlight you get on during the Winter months (could be as little as 1.5 hours) will determine the amount of solar panel wattage you need to replace those 240watthours per day you will be using.

So maybe 200watts of panel with an MPPT type charger or 300watts with a PWM charger.

[paulcheung]

When will be the 10 hours usage? in the day or in the night? That will help to determine your battery size.

[inetdog]

When will be the 10 hours usage? in the day or in the night? That will help to determine your battery size.

I am guessing that the reason for solar powered LEDs is that the spa is outside. In that case the lights would pretty much be useless during the day. Whether the usage would be all night, or just evening is a good question.
I cannot tell from the OP's post whether the 10 hour figure was what the existing photocell and controller combination provided as a default (or until the battery ran down) or whether that is actually what he needs.
It certainly does not make sense to run the lights long enough to run down the battery each night if the spa is not going to be used.

Maybe a DC powered proximity sensor would solve some of the problem.

[Mammoth]

the steps are off my deck down to the garage/carport the spa is in the middle.
yes i may be better to put some kind of motion scencor on them.: