Remote Solar Server

[new2u]

I have been playing with this setup recently and though others might like to see it.

Its an Acer One netbook that runs a web server, ftp, and mysql 24/7 (bought from tigerdirect for $239.00 it has 160gig hard drive and 1 gig of ram. Runs XP home edition and WAMP.

It runs from an 85 amp hour Marine cycle battery from autozone. The battery is charged from (5) 15 watts solar panels connected in parallel for a total of 75 watts.

There is a charge controller of max 7 amp hours 14 volts continuous.

The Acer is connected to a 400 max watt inverter from walmart.

Photo Album HERE

What is cool about this I guess is that it can be as remote as possible as long as the solar panels are able to see sunlight. Although the panels do not put out alot of power they put out power even on cloudy and over cast days.

What do you guys think about this type of setup?

[dnix71]

I own a Mac. I wouldn't have a web server running Windows unless it was where I had easy physical access to it. Windows isn't secure on the web. There is plenty of Linux web/music server software now that wasn't there 5 years ago.

[rossw]

What do you guys think about this type of setup?

Well, as previously mentioned, I sure as heck wouldn't be running doze on it. Security is only part of the reason. Power consumption is another. (Yes, I'm serious - the same hardware running windoze takes more power than if its running something more efficient)

Second, I can't see why you would run from batteries to an inverter then back down to low voltage again! Double-conversion losses are expensive, esp for solar applications. Go get thyself a CAR ADAPTOR for your laptop. It will almost certainly be much less inefficient.

Third, there are much MUCH better machines available, that take WAY less power. If you just want it as an FTP server and webserver with sql (and presumably php) look at something like open-wrt running on a SLUG.

I have a bunch of machines running webserver, ssh, ftp, email and monitoring/alarm systems on re-flashed and modified Linksys WRT-54GL routers - they run directly off 12V DC (so no power supply and conversion losses) and take about 6 watts!

[brokengun]

I will back you up on that, I have a friend who ran slackware on his laptop and would get like another hour or more of battery life from using that compared to windows. It just cuts out the fluff with an OS like that.

Also, how do you get internet if this thing is out there remotely? Through some satellite modem or something?

[richhagen]

I couldn't read the specs of the power converter for the laptop, but if it is 12 to 15 volts or so, you could probably run the laptop directly from the battery and cut out the inverter losses.  If it doesn't run directly, and if your model allows it, try running it with its internal battery removed if it won't run with it in at 12V.  I got an ASUS netbook instead of the Acer, and it runs off of 12V and will run directly from a battery, although I added a couple of paralleled 7812's since I didn't know the limits it could tolerate on the input power if the 12V battery was charging.  Rich

[rossw]

Also, how do you get internet if this thing is out there remotely? Through some satellite modem or something?

Several of mine run using 802.11b (wifi) several miles, at multi-megabit-per-second rates quite reliably (and have done so for more than 8 years in many cases)

I have others that use a USB "3G" mobile dongle that works over the conventional cellular phone network, although speeds over 1.5Mbit/second are rare.

[Madscientist267]

802.11b capable of 1, Several Miles?, and B, MultiMegabit? and then C, MultiMegabit over several miles?!?

Where are they set up? Antarctica?

[BigBreaker]

Google cantenna and you will understand.  A tube looking beam shaper sends a very directional signal to the target.  802.11b tops out at 11Mb/s theoretically and note that's bits not bytes...

Someone built an optical transmission system with LEDs that can get similar speeds assuming the weather cooperates.

[TomW]

Well;

I am at least 4 miles from the AP I use for internet access. My ISP [I helped build it] uses several multi mile links. Some up to 10 miles LOS between tiny burgs out here in the sticks. And one thats at least 15 miles. High gain, directional antennas of course.

We had to pick and chose gear for higher power units but it can and will work. Seems as capable as my internal LAN on speeds but haven't tested the capacity since we installed it all and I forget the original figures.

Just real world, hillbilly, boondocks silo to silo internet. Hilly terrain here so we had to chose where the gear went carefully.

Tom

[Rover]

First off, it works right? and you used stuff you were familiar with.. kudos on getting it going.

Yeah there is a lot of things that I and some others would have done differently. I know the Acer One is a small 10" screen laptop.. unless yours is somewhat different. But I would definetly figure out what it watt consumption is (you can get a ball park from the AC adapter label, work out the amps and volts for the output).

That is pretty much what you are going to need from the battery / solar arrangement.

Initially I think I would just keep an eye on your battery voltage on a daily basis, and see what the trend is. If it keeps going down..well you know the answer.

(This is in lieu of a whole bunch of other recommendations)

[RandomJoe]

Sounds cool! :-)

Although I too would use something other than Windows.  But then I've been using Linux for over a decade, so easy choice for me!

If yours is anything like my Eee, the inverter is MUCH bigger than it needs to be, you may be burning a lot of extra power on its idle current.  Although I've never measured the really small ones for idle draw, so perhaps not...  Mine only pulls 10W while running.  Max draw is 30W, when running and charging the battery.

The Eee's adapter is 12VDC, so it's tempting to just run it straight off battery, but I'm worried about the daily trips to 14.2V or a touch higher - I'll probably just get a car adapter for it to ensure 12V.  I have my other 12V network gear (WRT54G, cablemodem, Vonage adapter) right off the battery, but their wall-warts put out 13.6-14V when running anyway.  The Eee's brick is a rock-solid 12V even unloaded, so perhaps it's pickier...  (And I don't feel like risking letting the smoke out just yet either! ;-)

I had originally bought a fanless miniITX-style PC to use for my off-grid server / data collector / etc and was happy with it (indeed that's what I'm on right now) but it pulls 25W and that's just for the computer.  Most of it is the lousy Intel chipset.  I'm giving serious thought to another Eee just for the 10W draw.

I had thought about the SLUG as someone else mentioned, but last I looked those are discontinued so none are available other than Ebay?  And I'm just too cynical to trust Ebay... :/  I may wait, though, as there is talk of some ARM-based "netbooks" coming out soon.  Those should be lower-power yet.  If their performance is decent, I may just go that way.  The thing I like with the Eee is even at 10W, it performs almost as well as I expect from any regular computer.  I've even played movies on it (encoded from DVD at a high bitrate) without issue.  That Atom processor is nice!

[aususer]

I agree with all other comment'ers - eliminate the losses of the mains transformer (aka. wallwart/plugpacks) and inverter - you are losing lots of power there for little gain.

1. Consider trying to get your Solar battery to replace the one in the netbook. A hardware hack (so attracts the possibility of bricking it) but the gain could be worth it. Add DC:DC regulation to be sure. Maybe you could hack an OEM replacement battery - remove the batteries and install a DC:DC regulator + wiring to your solar battery system. Slide it when you want solar and replace it with the "real" pack when you want to go mobile.
   
2. Turnoff or elminiate the backlight of the LCD it is the greatest user of power (everyone knows "darkening" your screen gets you longer battery life). don't just display "black" when not in use, get the bios to turn the screen off properly.
   
3. many netbooks (eg EEEPC) have a linux version - disable the X11 platform and you have a cutdown host that you can run mysql,apache,red5 etc on.
   
4. Windows NEEDS graphics therefore lots of power and cpu use for very little return think "clock" in the systemtray as an example) - avoid windows for this reason (ignore all the "don't use Windows for anything becuase I don't like windows" comments - there is always a way to secure a system - windows or not - Unix can be hacked too... just depends on how secure you make teh system overall...
   
5. Are SSD disks (memory-based "hard disk") more power efficient and a better consideration? I know (by feel) they generate less heat - so that might indicate less power - spinning a hard disk platter does generates heat/friction = work = power use.
   
6. Keep in mind - anything that generates heat requires power - this will include harddisks, USB devices etc.. call it "parasidic power"..
   
   

Finally... my 2 cents on wireless.. 802.11b (or n) is possible over long distances..

You will need a level of radiowave-focusing to get it (be it Cantanna, Parabolic Ant, Yagi etc.. check rfshop.com.au for examples).

You sacrifice a few things with directionality ie. directly affected by items like LOS (line of sight), rain, wind (blowing antennas out of microalighnment)... Think an analogy of a flashlight vs laser - laser must be spot on.. but if it is you will get a VERY long way - but 10Km is POSSIBLE in a dead-flat world and has been done by people.

[rossw]

you will get a VERY long way - but 10Km is POSSIBLE in a dead-flat world and has been done by people.

In 2005 the world record was 275km (about 125 miles).

A couple of years later, using heavily modified equipment, a couple of guys in Venezuela managed 380km (235 miles odd).

Both of these were done in real-world situations (ie, near spherical world!) but did use height (mountains) to help!

I ran wifi over 6000 metres for 10 years to connect home to my office, at speeds of several megabits. Until recently, I also ran an access point for my wireless customers (I run a regional ISP here in Australia) and using LEGAL power and mostly over-the-counter equipment, had perfectly stable, reliable and speedy 802.11b links up to 20km

(By "legal" I mean our maximum EIRP was +36dB(m) or 4 watts of radiated power, one end was a fairly simple vertical antenna, remote ends all used gridpack type gain antennas)

[DamonHD]

I agree with the above and I do run my no-name Linux laptop (with screen off, SSD memory card 'discs', Laptop Mode, adaptive speed settings and tuned software to minimise power use, etc) at least in part on solar:

http://www.earth.org.uk/low-power-laptop.html

I get down to about 18W at minimum activity though could probably do better with a newer CPU.

Rgds

Damon

[Boss]

My day job as a WiFi installer has shown me that 10km is very doable. Using the proper gear helps and seven or eight years ago we did experiment with Yagi style Cantenna. These are very directional and difficult to keep aimed in the wind. For the cost a grill is better, Check out: http://www.pacwireless.com/products/point-to-point.shtml



Depending on the frequency being used a old satellite dish works well too. I cut off the LNB and braze a mast to hold a 5.2ghz Motorola Canopy

Looks like this this increases the gain by 18dbi, enough to triple the antenna power. We routinely install Dish mods to increase distance to 10 miles and more, if line of sight is there.

There is a new kid on the block that might be worth considering Nano Station 2 by ubiquity this manufacturer says 15 kilometers is easy, but I haven't seen it

Now this deal of using the old Linksys routers to flash with Linux is way cool,

 we have turned a $5.00 used router into a highly configurable access point comparable to a Cisco worth many thousands of dollars which unfortunately when Cisco bought Linksys they immediately reduced the flashable ram down to less than a meg to stop people from making these routers open source friendly. I am still waiting to find one on Ebay and have too many other irons in the fire at the moment. When flashed with Linux the Linksys router can be set to have different power levels on either antenna and use one for transmit and one for receive. Too many options for me to remember.

Linksys WRT54G series

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Linksys WRT54G version 1.0

Linksys WRT54G (and variants WRT54GS, WRT54GL, and WRTSL54GS) is a Wi-Fi capable residential gateway from Linksys. The device is capable of sharing Internet connections among several computers via 802.3 Ethernet and 802.11b/g wireless data links.

The WRT54G is notable for being the first consumer-level network device that had its firmware source code released to satisfy the obligations of the GNU GPL. This allows programmers to modify the firmware to change or add functionality to the device. Several third-party firmware projects provide the public with enhanced firmware for the WRT54G. See Third party firmware projects.

[rossw]

My day job as a WiFi installer has shown me that 10km is very doable.

Thats no longer up for debate. Plenty of us have already stated that we've been doing this for years.

Using the proper gear helps and seven or eight years ago we did experiment with Yagi style Cantenna. These are very directional and difficult to keep aimed in the wind.

Utter nonsense. If you are "using the proper gear" you will know that proper, rigid mounts are not optional. I have 26 element yagi antennas (in radomes) mounted on the top of hundred foot towers on top of mountains over here in Australia - that are regularly subjected to winds in excess of 140 kmh. They run links over 8Km and have never needed re-aligned in the 6 years the link has been running.

Depending on the frequency being used a old satellite dish works well too. I cut off the LNB and braze a mast to hold a 5.2ghz Motorola Canopy ....  this increases the gain by 18dbi, enough to triple the antenna power.

Whoa there buddy! First off, 18dBi gain is NOT tripple the power. The dB scale is logarithmic. 3dB is DOUBLE the power. 6dB is double that (4 times). 9dB is 8 times, 12dB is 16 times, 15dB is 32 times and 18dB is 64 times the power.

If I recall correctly, the Canopy was already +30dBm (1 watt) so you're poking 64 WATTS of RF out the front of that thing. I'd be very surprised if thats even LEGAL. It absolutely, definately is NOT legal in my country. Max legal power is +36dBm (only +30dBm in some bands, and I think that may also apply to 5.2 and 5.8GHz ISM bands)

As a "wifi installer" I would have expected you to know about power gain, and also to be aware of and sensitive to the legal requirements of installing and operating links in a safe and legal way. (set up your 64W unit and point it at someones house, in an day, they could get as much exposure as sitting in a microwave oven on high for over half an hour!)

Now this deal of using the old Linksys routers to flash with Linux is way cool,

 we have turned a $5.00 used router into a highly configurable access point comparable to a Cisco

Been doing it for years. I think I may have mentioned it earlier in this thread, certainly been discussed numerous times in IRC.

The LinkSys IS cisco and has been for quite some time.

unfortunately when Cisco bought Linksys they immediately reduced the flashable ram down to less than a meg to stop people from making these routers open source friendly.

I doubt they did it to stop people re-using them. I expect it was a way of reducing the manufacturing cost so they could increase their profit, and stopping people re-using them was just a bonus.

You ARE aware, are you not, that the WRT54GL is still being made, and still has the full FLASH and RAM, and can be purchased brand new with warranty quite easily? (I just purchased 10 more for another project. Sure beats waiting forever for them to come up on ebuy and having to deal with every different hardware version!)

There are also HUNDREDS of other routers readily available that you can reflash with one of a variety of linux specifically developed for this application? Check out open-wrt, dd-wrt, tomato etc. I've got a couple of Motorola wr54g routers here I've reflashed and several other one from other manufacturers. The linksys just happens to suit my needs because of its physical construction and ready availability.

[Boss]

Boy am I humbled.

This is pretty good information all around.

I hope the info that I provided was taken well, anyway.

I don't feel inclined to argue under these circumstances, which is counter to the boards design. But oh well, what can I say?

Conversation stoppers abound