Solar panel sizing for Bullet 5

[mchapman]

Hi,

Can anyone provide any suggestions as to the minimum size solar panel I could get away with using along with a Bullet 5? I am looking to use a 125 hour battery that would provide 3 days of battery power ( in conjunction with a 3 watt camera). I am located in North Carolina.

Thanks for any input,

MIke

[laser3]

I'd say perhaps a 20Watt panel should do the trick providing you get good sunshine atleast every other day or every 2 days if the sunshine pattern is less than that which i don't think it is then you may need something higher

[mohave_steve]

I have been researching the same question.

I was suprised when the "Solar Expert" I spoke with told me I needed a 600watt array to properly handle 3 Nanostations and a 4port switch.

While I still think he may have gone a bit overboard I did come to the conclusion that to keep remote stations running 24x365 does require alot more solar capacity than I originally suspected.

Start with the usable sunlight at your location on the shortest days:

http://www.advancedenergysolution.com/Resources/solarisolation.htm

In my area the shortest days have a solar isolation value of 2.01 hours.

I am hoping that I will achieve 70% efficiency in my charging/storage system. I don't know if this is realistic yet.

I have to allow for capacity to not only run the radios but also to recharge the battery after several cloudy days. If I were sizing for my area:

Load:
1-Bullet 4watts
1-Camera 3watts
Total 7watts x 24hrs/day = 168 watts/day

Charging/Storage capacity:
120watt Panel
2hours output on the shortest CLEAR days in winter.
70% Efficiency
Total 168 watts/day

Now I haven't allowed capacity to recharge the batteries after a few cloudy days. Perhaps 10% additional capacity would be ok?

I have not tried solar yet. I have ordered a panel for testing to compare real world performance with calculated numbers. If you can believe the calculated numbers then you would need about 200watts capacity solar to run your site.

[mohave_steve]

Well after doing all of the math for SE Washington I looked and saw that your solar insulation value is 4 in the winter. That would (as I understand it) give you the ability to support your site with a 100 watt panel. Or perhaps you could install a 200watt panel and email me the excess watts to run my solar site? javascript:emoticon(':D')

[rconaway]

Just move to Arizona and your costs drop signficantly.

Keep in mind the cost of controllers and inverters if you are using them.

[sunwize]

With a 7w 12vdc load (bullet + camera) and a Greensboro site figure 80w of array.
Your battery should provide you 7 days of autonomy with this load.
Let me know if your interested in a system solution.
Regards,
Bob

[WHT]

Lotta "page not found" on the sunwize web site.

[WHT]

http://forum.ubnt.com/forum/viewtopic.php?t=5894

[mchapman]

Thanks for all of the input. I think I will try out an 85 watt array with a nice size battery pack. It will be a great learning experience for me, although it could get a little pricey :)

Now if I could only learn how to use RadioMoble!

Mike

[mohave_steve]

I am picking up an 80watt panel and an 85a/h battery today. I am going to run a single NS2 for a week and log current draw, charge current & battery voltage. I think this will help me get a better handle on real world performance.

Over the next week we are expecting rain, snow and later single digit temratures. Between the cloudy weather, snow accumulation and cold temps I think this will be a good test of near worst case conditions.

I'll post my results.

[Wifi442]

I would take a look at this site and these calculations. I am designing my solar installation based on this method of calculating. The member "Sunking" seems to be quite knowledgeable

http://www.solarpowerforum.net/forumVB/showthread.php?t=1793

[kijoma]

hi,

it is normal to combine solar with wind power, far better chance of having one or the other that way..

[WHT]

I had a small 40 foot wind turbine...it failed about 5 seconds after the self-propelled lawn mower got tossed over the back yard 6 foot chain link fence. An F1 tornado can be such a pain in the ****.

[sunwize]

Did your solar plant install work out ok?
Regards,
Bob

[parkland]

Wind power is cool and useful, but my my opinion is that solar is better for this kind of thing as it has no moving parts, and remember that even overcast & semi overcast days the panels still pump out SOME power.

I sell solar stuff so I know a bit.

[dextercath96]

I suggest you to visit this link so that I can provide you the informations you need. http://www.sunpowerport.com

[Dave-D]

Sorry Dexter, but that 'sunpowerport' device you
list doesn't make much sense. It shows a 28W
solar panel and a 12V 12AH battery. Then it says
the battery can power a 20W light for 10 hours.

20W at 10hours is 200W-H, of course. But that
battery is 12V x 12A-H = 144W-H. And you should
never (as WHT pointed out) discharge a battery
below 50% of its rating; in this case 70W-H.

That means the lamp can be powered for 70W-H/20W,
or 3.5hrs. This doesn't even include the loss due to
the inverter, perhaps another 10% or 0.5hr. less.

In any event, a solar panel and battery that size won't
keep up with a daily load of a Bullet at 4W and a 3W
camera, total 7W. In a 24hr day, that's 168W-H. Two
dark days would require at least 250W-H of battery.
At 50% discharge, that's a 12V 40A-H battery. Dave

[WHT]

http://www.ubnt.com/forum/showthread.php?p=71889

sunpowerport.com....Hmmm, it don't pass my sniff test. Sorry
That's two hundred watts.

and....


That means is can collect 120 watts per sun day.
Where does the other eighty watts come from ????

[dextercath96]

Why don't you try it? There are no lost in trying. http://www.sunpowerport.com

[WHT]

Why don't you try it? There are no lost in trying. http://www.sunpowerport.com

MSRP: $695.00

Is not a "no loss" for a product that doesn't pass the sniff test.

I'll gladly redact my comments if the manufacture want to send me one to evaluate. Until that time, I'm not going to spend $695 for a eventual door stop.

[Vance G]

Besides, this device has all kinds of stuff you don't need, a case, an inverter (Bullets run directly off DC and with their wide supply voltage range are an excellent fit for a 12V solar system), pointless LED digital readouts (that consume part of the device's own power to operate - stupid), etc, etc, etc. All things that needlessly add to complexity and that can break.

I have a B2HP running in Southern Utah off of a Kyocera 65W panel and a 90aH AGM battery. It has been up continuously since I set it up (70+ days) through several snowstorms (we are at 168% of normal for snowpack this year) and many nights with temps. in the single digits.

Total cost of the solar components for this setup was under <$500 and it has much more capacity and is more appropriate for the situation than that briefcase will ever be.

Image attached so you can perhaps get some ideas for your own install. Battery + charge controller are in the Contico Tuff-Box buried about 2' deep (right side of mast with lid open) to keep the battery as warm as possible in the winter and as cool as possible in the summer.