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Laptop vs. Small Desktop: Best Bang Per Watt?
Deagol writes "Tomorrow I take possession of a remote, wooded lot with a cabin. 15 miles to the nearest utility pole, my electricity options are limited to those I can generate myself, solar being my primary goal. I'm sitting here staring at my power meter, seeing my desktop & monitor draw about 250W -- a non-trivial amount to generate over a 8-to-12 hour workday. I'd be happy with equivalent computing horsepower (1.4GHz T-Bird, 512M RAM, though more is always better). Should I get a small PC with an LCD monitor, or should I get a laptop? Will laptops draw less power (in general), and if so, will losing the modularity and lower cost of commodity PC parts be worth it? I'd love opinions from those who have been in a similar situation."
Duder, if yr headed that far out into the boonies, you might as well pawn the damn computers and buy an axe and a box of matches. Seriously.
sig not found
I feel that my laptop gives me more bang for my buck. It draws much less power, and I can take it around with me. I like it much more than the cheap pc's we have at work (which would be a low power desktop) but LCD monitors are nice, but the quality of the lcd's on a laptop are just as good.
And I didn't know Ted Kaczynski was even eligible for early release...
-- @rjamestaylor on Ello
...that way you can always charge it up from someone elses sockets.
An infinite number of monkeys will eventually come up with the complete works of
are you going to do out in the middle of nowhere with a laptop? Leave the fucking computer at home and spend time actually being outdoors hiking or fishing. Read a book, spend time with your man or woman, anything but a computer.
Only the State obtains its revenue by coercion. - Murray Rothbard
I'd be willing to bet that the power savings from getting a laptop, as opposed to a desktop with a LCD, will be sufficient that you will more than make up the price difference by being able to buy slightly fewer solar panels and batteries.
Solar power is not cheap.
"The worst tyrannies were the ones where a governance required its own logic on every embedded node." - Vernor Vinge
The batteries in a laptop will give you the flexibility to work independently (for an obviously limited time) of your home's power source. This might come in handy if you have a solar system that has intermittent output or oyou have other high-draw electrical needs.
The big problem you'll face on solar is the ol' "It don't work when the sun ain't around." That means you're better off getting a laptop for a few reasons. 3 or more hours of battery life can be very handy and you can march around with it, meaning you could leave lights off at your desk and stroll over to the kitchen with your laptop, saving electricity in two ways, the lights and that stored in the batteries.
Another option is get a UPS for your desktop. You can run the machine off of that when the power goes out, night, etc. and they are relatively cheap...if you get a 4 hour one... and can power other devices. The laptop and the UPC will trickle charge while juice is flowing, so you can be pretty sure that when the sun does set, you won't miss a beat with your tech.
Now... how exactly are you going to get on the net? Satellite? Pigeon?
"Life's funny sometimes." "And sometimes it isn't." --Cat's Cradle
It should be obvious that there are more low power options in laptops than PCs.
However, be aware that some laptops are really just mobile desktops, in that they're fast, hot, and hungry.
There are plenty of good low power laptops out there. Just start by looking at battery life.
"Small PCs" are not necessarily better for power consumption than big boxes. It all comes down to the CPU and graphics cards, mostly. OTOH, I can attest that a lovely little Shuttle XPC with a big fat P4 will probably be enough to heat your cabin thru the coldest winter. Mine was like a hairdryer permanently on.
.sigs are for post^Hers.
There are many different alternatives. Yes, using a laptop is much more power-efficient, and you can get yourself power-adapters to convert DC to DC current to charge your laptop from a 12v battery car.
However, there is also a Mini-ITX form-factor system, to which you can find cases with built-in DC switching power supplies.
I think the solution is to stay native to DC current, and then convert as you see fit. So, all you need to have is a set of car batteries, connected to solar panels (for charging purposes), and you set-up some sort of power distribution & management system.
I'd love opinions from those who have been in a similar situation.
Error: division by zero
Try looking at what they have here: solarpc.
They even have a complete turn-key squeak system (it's at the bottom of the page): here.
You might as well get a laptop. Most of your time will be spent elsewhere than the cabin. In a multi floor house, you will benefit of the true portability of a laptop.
If you're just running 3-4 PCs, what's the point? Get a Belkin (cheaper) or APC (better Linux support) unit and get the same digits.
The person asking the question states that their desktop is sucking down 250W for PC plus monitor. My laptop (Fujitsu C2220 running Linux 2.4Ghz P4 and 512Mb) has a power supply rated at 100W and draws around 90W. Previously I've had Dell laptops that draw 60W. If you go get an Apple iBook instead then they draw only 45W.
Laptops make perfectly good computers, except as very high-end workstations/gaming machines. I have not owned a desktop machine for at least the last ten years. The small amount you are behind in terms of graphics processor or CPU is more than made up for by the ability to take the thing with you.
John.
The laptop has power conserving options and its own battery source. The laptop will give you more flexibility. Plus, you can take it on business trips to meet with other hill billies in the co-op. Imagine the waste of powering the desktop on and off.
Plus, Thoreau, you can take a bag of batteries over to your moms there and charge them up.
What will you use the computer for out there? Reply.
not sure how much sun exposure you have avaliable, but a laptop plugged into one of these has to last a fair while.
:-)
might even come in handy in new york next time the power goes out.
A Pentium M laptop with long battery life would be a good choice for its low-power consumption.
Come on now, a true nerd would build a steam engine to run his generator. You clearly have some wood around. Sure the conversion efficiency is only 5%, but think of the nerd points you'd get for posting pictures of your steam-powered computer! ;) And, if you are really nerdy, you could even try for a Stirling engine, which could also be run in reverse to cool your CPU.
- can take it with you
- can pre-charge the batter elsewhere when possible
- has built-in "UPS"
- is specifically designed to use as little power as possible
- if you later get a generator for the rainy day, the battery gives you time to start the generator without hibernate/shutdown
- if you want the comfort of separate keyboard, bigger LCD, real mouse etc, you can still get them for laptop too (and getting that 2nd LCD may give you dual screen as a bonus) and still use less power
Whilst I can't say much about power usage I can say that a few months ago, I decided that my big old XP1600+ beast had to go and that a quieter, more bedroom friendly solution was required.
:)
I chose a laptop over a small, quiet PC mostly so I could take it to Tafe, Uni, LANs, etc on public transport, which doesn't sound like it will effect you much.
The point is, that it is quite possible to get a laptop to replace your desktop, especially since your computing power requirements seem to be similar to my own.
Personally, I managed to find a nice looking (Mac design clone) laptop with plenty of power for my needs. I was set back $2,600 Australian dollars for a Pentium M 1.5ghz, 512mb RAM, 40gb HDD, Geforce FX5200 Go and a 15.2" widescreen LCD (just as wide onscreen as my 17" CRT, slightly less tall.) Expansion wise, there is the one PCMCIA card and the internal MiniPCI slot which came with an 802.11b card inside.
My needs were also based around portability, and being a thin and light, this notebook weighs 2.7kgs. However, since you'll not likely be walking to the nearest LAN party from that location, I do think a laptop designed for good battery life will obviously use less power. Between the slower hard disk, powersaving, speedstepping CPU and powersaving motherboard, you could be using far less power than all but the best designed MiniPC. Another advantage to the laptop is that you get a few hours battery life in case your power dies or runs out of juice. Perhaps you could even take it out roaming your property if you're into that kind of thing.
Think I've rambled on a bit, but hope it's been helpful.
Seems you'd just need to stop by Home Depot and pick up about about 792 100' extension cords...
Consider: 1700$ for a really nice laptop (Such as an IBM Thinkpad X31) which has good battery life (5ish hours) and meets your requirements, has APM/ACPI support, has the ability to down-clock the processor per your need, and draws -much- less power than a small system/LCD combination even without any real management, and no/few power cells needed (depending on how frequently you plan to join civilization, and how much you plan to use the computer).
Or: 600$ for the desktop/LCD combo, with no APM/ACPI, with minimal/no real power management, vs. a compact and portable laptop that can have function outside of the woods in real life in addition to its getaway use, and a shitload of solar panels (or just a few and a large number of car batteries to store the power over time - still a large expense).
I'd personally suggest, that, given your desires and requirements, that you go with a low-power laptop (such as a Fujitsu or IBM thinkpad X31 - I love my X30) and one or two solar power cells: however many it would take to continually charge a 12V car battery or two. That way it can charge while you're gone, and you'll slowly wear down the charge while you're there over a period of a weekend or so. If you go there less frequently, but for longer periods, just get one or two cells, and half a 12V batteries - it'll provide power for a desktop for a day or so, your laptop will be set (especially if you come with a 5hr charged battery at the onset, and you run off the batteries after the laptop battery is used).
Personally, though, I think you're bloody nuts. You've got a nice cabin out in the woods, away from modernization and electronics - what in the world are you thinking, bringing a laptop with you to compute while there? What about spending the time to let your soul relax, to do something different? Why not go out back and chop wood for relaxation? Why not read a book by the fireplace at night? Why not go hiking with a sack lunch, with no descriminate plans for the day?
To behave in such a way as you're considering, in such an environment, is a shame. It's no small wonder that our rainforests are being destroyed, the environment is being poluted, and people still don't give a damn.
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
Get yourself an IBM Thinkpad X30 from the authorizes IBM Ebay store. These are heavily discounted (overstock) NEW laptops with a full warranty.I recommend these for several reasons:
Very durable, small -- won't take up that much space in your cabin
12" screen, more than adequate for general purpose computing, plus the smaller backlight mean considerable power savings in the long run.
Get yourself a couple of deep cycle marine batteries. 1 to use, the other being charged.
Do you want to build your own windmill? Looks like fun project.
P.S. I don't know how remote your cabin is, but if you get yourself a Proxim/Orinoco WiFi card (these have external antenna jacks) and build/buy from a ebay a hi gain 2.4 Ghz yagi antenna, you might be able to hit someone's WiFi AP. It's worth a shot/ fun to try.
If you do by any chance get WiFI with this setup, update your journal and let us. It would be cool to know how you accomplished it.
--
3-5 hr battery life depending on usage.
Solar power is generated and stored as direct current. In order to use a desktop system, you will need to convert to AC, so that the computer's power supply can convert it back down to the proper DC voltages. This is a wasteful process.
If you start with a laptop, preferably one whose input voltage is the same, or lower, than the voltage of your storage cells, you will make a more efficient use of your power system.
-Chris
-- This sig is only a test. If this were a real sig it would say something witty. --
...due to going from 120VAC->12VDC that both computers actually use. If you get a desktop, the power supply does it, if you get a laptop the power adapter does it. Maybe the laptop will use less energy because there's no fan on the power supply but either way you are still going to lose a big chunk of energy due to the conversion. I can barely hold my laptop power adapter it gets so warm...that's got to be more than a few watts.
What you should do is get yourself a computer with a 12VDC power input. They sell power supplies that take in 12VDC and have standard motherboard power connectors (although the last time I shopped for one it was using AT connectors). They work well for computers used in cars and boats. A little more expensive, but they basically take the power in and put it right to the motherboard and components.
Speaking of cars, will you have one? Why not use that as the power source? Get a laptop with a ton of extra batteries and keep three or four charging from car adapters wired into the car's trunk or something. If you get a laptop with a mobile processor that sips power, you should have well more than enough power. I work with a Dell Inspiron 600m and I ususually get 3-4 hours per battery. I have two spares I can hot swap so it is easy for me to go an entire 9 hour day running off of batteries.
Also, how much storage do you need? Why not go completely solid state? You could boot from say a CD, load everything into RAM and then power down the CD drive. At that point all you need is a USB key or other flashram to keep your data safe and that should be it. No hard drive, no CD-ROM should mean a lot less power right? Those are both big draws on my laptop.
Those are just a couple thoughts I had...
- JoeShmoe
.
-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
If you start looking for low power CPU's, such as ARM's you can drop your power by a large factor.
---- Booth was a patriot ----
They also have sensational battery life. My old g3 pizmo w/ 2 batteries would last 8 continuous hours of word processing. And would do a week business trip of casual use without recharging. My TiBook and iBook get about 3 hours of casual use (w/ airport).
If you have no religious preferences about computing then the Apple will give better power performance. The G3 iBooks are coming in cheap now. Especially, refurbed. Then you can save money for the solar setup that is going to hurt more.
Consider a lot of the same factors for desktop or laptop.
If you can sacrifice a little performance, you will find that a system that uses a Transmeta Crusoe or a VIA Eden CPU will consume far less power than anything from Intel or AMD. There are a few nice Transmeta based laptops.
Both provide good x86 instructions and run XP or linux fine.
As well, going with a small (15"-17") LCD will be a big power saver for a desktop over a traditional CRT.
Use a lower RPM disk, or a laptop drive in your desktop.
On a laptop, if you can live with dual scan it uses less power than active matrix. If you can find an "organic" LCD like the one in the Gameboy Advance, they use the least power of any acceptable display technology I've seen.
Also don't forget to optimize those energy savings times to get the components to "sleep" after just a short idle time.
Cheers!
~8^]
I'm not sure if this will produce better power savings than a decent laptop, but it should save some 30% on power if you are going to use a PC.
I assume that you use solar power to charge up 12v batteries. Running that power through an inverter only for it to eventually get converted back to DC is hugely wasteful for a variety of reasons(A horrible power factor being one of them).
I just googled around, and found this page with a variety of DC/DC PC Power supplies, with a variety of supported voltages.
Now that I think about it, if you have the capability to supply the power supply more than 12 volts(ie: 24 or 48 volts), then that will probably improve your wattage even more(as well as improve your stability if your power is "dirty").
Pair this with a small, power-saving bare-bones PC, and I would imagine you would have a setup that would be comparable in wattage to a laptop. Perhaps even better, considering that you are still using gobs of power from the DC->AC->DC conversion when charging the laptop batteries.
Finding a DC LCD Monitor may be a bit harder, but I'm sure they are out there somewhere. If you are feeling adventurous, you could even modify a monitor for DC...
— darco
off my Powerbook 12inch power supply:
- Input 1.2 Amps.
- Output, 24V, 1.875 Amps.
Of course, a laptop will not likely draw the most power, the SATELLITE dish you need for the net connection... unless your bazillion acre lot has some GPRS coverage (yeah, right)...
Having lived on a 1000 Acre camp, I can tell you the DIRT is what will really drive you nuts, good luck.
A word about laptops. Most of them have two modes they operate in. While running off internal power, they run in a low power mode. This many times slows the CPU down and dims the display. Also while in battery mode the fan will run on various speeds on demand.
When they are plugged in they speed the CPU back up and brighten the display - consuming more power since it is available. I think I would probably recommend a laptop, and a few spare batteries. Then you can charge on someone else's power and bring it back home with you.
Since your laptop will use less power when running off battery you should always use your laptop on battery power. Then when you shut it off you should charge the batteries. Make sure you get a laptop with two bays.
If you go with a PC get a variable speed CPU fan with a sensor. Then it can slow down when it is not needed, saving you some juice. Since I am assuming you would be building your own system then evaluate the watt consumption of each component, and add it up getting a good quality (expensive) power supply that meets your needs without exceeding them astronomically. When possible use one component instead of two (Optical drives, hard drives, memory modules, etc.) Two will consume more juice then one (obviously) when you can get a single hard drive that is big enough to do the job.
Display brightness has a huge impact on battery life. Whatever you go with make sure your display is as dim as possible. Put your computer in a dark room.
Also, don't run SETI@Home, GIMPS or one of those other background processing systems. Those really increase your machines power consumption, as do games!
Another must have would be a good UPS with a power conditioner. Brown outs are very damaging to your computer hardware. Not that I doubt your ability to build your own power grid, but wouldn't you hate to loose your PC because of a brown out?
"Anything is possible with enough programmers, time and pizza." (Substitute caffeine for time as needed.)
Laptop Pros:
1) A very small form factor that is easily portable, and easily stored out of the way. My experiences with cabins say that this is good.
2) The built in battery is a very effective UPS which is good when you are dealing with unreliable power sources (solar, etc).
Laptop Cons:
However, laptops are designed to be power efficient when running on battery, not when plugged into the wall. Depending on exactly how the battery charging works, they could be very inefficient when running on external power (like some UPS's are).
For example, I know the external power supplies draw some power whenever they are plugged in, not just when they are connected to a laptop.
plus-good, double-plus-good
Someone brought in a current meter in my computer hardware class. A p-133 PC with HD, Nic, vga, CD, and floppy drew 40 watts. Throw in a 14" crt monitor and it drew nearly 175 watts. So a normal PC wouldn't be that bad, just go to a LCD display.
If this is a cabin, you're probably only going to be there on the occasional weekend. In which case get yourself a laptop and a gasoline generator. You can probably get by with one of the dinky little Honda EU1000's. Whisper quiet, stingy on gas and should run your laptop, charge your cell phone battery, a couple lights, maybe a portable TV and small frig (maybe not all at the same time). It won't run a full size frig or electric heater, but it's easy to carry. Around 800 dollars. If you need more power, a Generac 4,000 watt is quiet, produces clean power and should run most of the weekend on 5-8 gallons of gas (depending on usage). Lot cheaper than Honda's for the same amount of power and that will run a full size refrigerator, heater, TV, satellite receiver, whatever you want. Home Despot, around $750.00. It weighs about 150 lbs (on wheels), so you'll need a pickup or small trailer to haul it back and forth.
With any generator you have to look at the sustained wattage and surge wattage. Honda tends to advertise their surge wattage, which a generator can't maintain very long.
If you ever decide to live up there permanently, you'll want to look at either a big solar or combo solar/wind system. Figure on 15 to 20 thousand depending on the wattage you need. If you have a stream or spring, you're golden. Hydro electric is the cheapest and best, until the creek runs dry.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
If you really need a computer in the middle of nowhere, buy an Apple LapTop (iBook or PowerBook, first needs less power).
...)
Anyway, I'd suggest doing anything but use a computer.
Man, enjoy nature! (wildness, mountains, girls,
Tend to post comments only when drunk
I chose laptop, even though I do 3D rendering. Everybody here has told you they use less power, yadda yadda yadda. One of the main reasons I went laptop is in consideration of a few things.
1.) I move about once a year. I'm sick of lugging my desktop around. When it goes extinct, that's it for desktops to me.
2.) I wanted an LCD that'd do 1600 by 1200, and the cheapest I've found those is $1,000. My laptop was only $700 on top of that. (Yay for Dell.)
3.) When it's time to replace my laptop, this one will still be useful. I have 4 towers at home that'll never see the light of day again, but the laptop I bought back in 99 is still finding use as a web terminal. (plus, selling them is easy.)
4.) I'm no longer sold on the upgradability factor. By the time mid-range processors are 4x what I currently have, I've saved up enough for a new laptop. I'm not the type to drop $500 in a vid card for a few extra FPS. (Lately I've been gaming on my Game Cube anyway.)
5.) Extra desk space. Need I say more?
My current desktop has been promoted to 'server', and I send it rendering jobs to do once in a while. Eventually I'm just going to hide it in a dark corner somewhere.
"Derp de derp."
Now... how exactly are you going to get on the net? Satellite? Pigeon?
He should prolly stick to the tried-and-true bongo drum method. They've got better range than wireless, low power consumption (well, other than mechanized sticks, but he could just operate them manually on cloudy days), and complement the decor marvelously!
Don't forget to mention how this is accomplished. You will need what is called a DC-DC converter. They sell universal ones at retail outlets where you just pick which connector your laptop uses. It is ment to be powered off 12V DC (like a car or marine battery or alternator) and basically cleans up the source, and splits it into 12v,5v, and 3.3v rails.
If you use solar pannels with the standard laptop power supply, you are seriously wasting lots of electricity in the form of heat.
Also watch out. if you are going to go all DC (ie, no power inverters for AC) then you will want to make sure to keep your power cables from the pannel to the house short and thick. low voltage DC current isn't like high volt AC. Longer and thinner cables won't carry your electricity very well and will greatly reduce the wattage your solar pannels will provide to you.
Two infinite things: your stupidity and mine. But I'm not sure about the latter. If my sig offends you, I'm sorry.
According to the insurance industry, 50% of all laptops get stolen.
According to the naturalists I know, grizzly bears are extremely smart, and damn near unstoppable when they want something.
When the grizzlies look in through that window and see that shiny new glowy-apple Powerbook, you *know* they're gonna want it.
Just be careful out there, is all...
Eloi, Eloi, lema sabachtani?
www.fogbound.net
I've been trying to minimize my power usage for some time and have measured several different systems using a watts up meter. (Unfortunately filtered through my memory)
I think the newer eden boards are a little bit better than the C3 in a ordinary mother board.
I think my G4 powerbook averages about ~15 watts as well. (Charging is closer to 30 watts.)
The important note is that the laptops include the LCD monitor whereas I was running the desktops headless.
Also to cut down on energy lossage with either the small desktop or the laptop try to get a DC to DC power supply. From what I've read an inverter will sap another 10 watts.
Also if there's already some sort of battery or capacitor in the solar power setup don't even run teh laptop with the battery in - why waste any power charging batteries - just put them in every week or so to top off.
Same goes for anything else, anything that runs on DC power you should hardwire to avoid the redundant conversions.
A friend has a place far from anything. Has phone, but no power.
6 solar panels -> a number of truck batteries (and charger) give him loads of power. 19" TV from the 80's works, usually, til midnight.
Gas for stove/fridge.
A couple of the panels are from the 70s. 80% of their orig efficiency.
His best investment of late was a new inverter. THOSE have gotten LOTS better in the last few years.
LCD absolutely.
Laptop has a UPS :)
Laptop can easily be rigged to take DC (48V or 24V solar is common). So why go from DC->AC->DC?
Also, you may not WANT the computing power of a full desktop.
Ideally, you could have an ARM computer or perhaps Intel/Apple might offer slower/lower power boxes. That said, are ibooks lowerpower than Intel boxes? The chips generally are.
My iBook (and I assume all Apple laptops) have an Energy Saver Preference Pane where you can control when the computer is put to sleep, when it dims and turns off the screen, processor performance, and if it spins the hard drive down during periods of inactivity or not. It has different settings for battery and power adapter modes, but you can set it to run in the same low power modes when it is on the power adapter.
I would suggest starting with a rough power budget and working from both that and the monetary budget to figure the best trade off. Firstly do you really need a 1.4GHz athlon worth of power - no laptop today that is low power really has that.
For the VIA EPIA type desktop systems with the right LCD displays you can get the power down to about 55W including monitor (thats a real configuration EPIA M6000, Keycorp K57H + 12.1" TFT display, 256Mb, and a disk)
Laptops take you a little bit lower and you get the benefit of the battery being pre-fitted of course. That means looking for real low power laptops - crusoe, anataur, maybe PIII-M as well as making sure they have good power control in your favourite OS and preferably suspend to disk so you can kill the drain entirely when its off.
The CPU is critical, you can get "micro" P4 boxes but they still burn the same power, just in a smaller space. Large boxes can actually use less power because you need less fans!
I can't believe a fucking troll has a 4, Insightful moderation that's lasting so long. Bravo, Sir!
;-) If the guy wants to use his freakin computer while he's taking a sabbatical in the boonies, big freakin deal!
Perhaps you should open your eyes and notice that not all of us sign up to your conformist 'everyone must be in a couple' bullshit
(And fishing is boring as hell anyway)
mogorific carpentry experiments
Listen,
Both a notebook and a desktop system suffer from the same thing: They both run on 110AC. Inverting your DC solar power to that will cost you 30-40% of your power. Converting back to DC (for your notebook/desktop) will cost you a second round of 30-40%. This is bad.
Find a method that can keep you at DC power, ideally as close to the voltages you need. Many of the mini-itx boards will have an option for 'dc power'. These will run on 12-15 volts, and will cost you more like 10-15% TOTAL. Plus, many of the mini-itx boards will consume far less power - - some of them as little as 15-20watts. You won't quite have the speed mentioned (1.7ghz), but close to it (900-1200mhz).
You could use a notebook & build a native DC supply for it - - but many of todays notebooks, regardless of size, draw MASSIVE amounts of power. My dell notebook draws 3.5amps@20 volts [70watts]. That's at 1.2ghz/512megs of ram/15" screen.
As others have pointed out, you'll need power storage. This can be calculated based on your consumption & number of panels used. You can lookup the typical number of solar hours per day for your region.
Solar panels cost around $1USD per watt. The charge controller & storage will also be somewhat costly - - do some reasearch, and purchase a few books on the subject before spending to much...
Not the fastest, but reasonable performance. I don't know how much electricity it uses, can't be much, makes little noise and barely even gets warm.
HenryJamesFeltus.com
I'm in the process of building (year #5, woo-hoo!) a totally off-grid home in (almost) the middle of nowhere. I've gone through this already.
The short answer is if power is all you care about, a notebook is better. My Sony TR1A consumes 13 watts of AC when plugged in at full-tilt according to my power meter, and display-off sucks just 5 watts. However, I care about more than power, like uptime/durability, ability to use off-the-shelf components, and being able to support some modest external hardware, so the actual system that stays on 24/7 is a VIA Epia 533 MHz box. It takes about 11-12 watts but can peak around 24 watts or so, plus a 15-inch LCD monitor which is pretty much never on, but consumes 16 watts when it is; so you're looking at about 30 watts with one of the lowest power desktop configurations possible.
Other odds and ends consume power as well. Inkjet printers are great (Epson C82 sucks 1 watt in standby, about 5 when printing.) Larger ethernet hub-like things are about 5 watts as well. (That'd be hubs, terminal adapters, wireless routers. nearly everything in my 3com officeconnect stack at my real house is 5W per unit.)
As far as power budgets go, it's the time the devices on that really gets you. An 18W average setup running 24 hours a day is 432 watt-hours, almost half a kilowatt hour. While I have a pretty substantial solar array (1 KW at the moment) during the winter I'm going to see maybe 4Kw-hours per day, so I'm burning nearly 10% of my capacity on just one PC.
So.... you can use your kick-ass system if you want, and if you limit it to one hour a day v. 24 hours a day, you'd be ahead.
BTW, my losses on the total system aren't bad at all. Inverters and batteries are pretty efficient these days. I'd gladly accept a 50% loss on storage and conversion, however, if I got 50% efficiency out of the panels instead of the sub-20% that's typical of solar today.
As with most things marine, the 'marine' classification doubles the price instantly. Better look for traktion batteries that are used in golfcarts and forklifts etc.
As always with batteries, you pay for better quality, and just because lead ain't cheap either.
You are not supposed to run these dry too, discharging till 50% gives a much longer lifetime.
This space is intentionally staring blankly at you
1. Use a laptop. A real one. The cheap desktop replacement with p4 and everything suck well over 100W. Get a light weigth laptop. You should be able to get something with p3-m that draws an average of less then 50W. I personnaly love my Thinkpad X20.
2. Use deep-cycle battery (used in boats and some RVs) they last 2-5x longer (both in number of months you can use them and in how long you can suck power from them before they're fully discharged) then car batteries so you won't need to replace them every 3-6 months.
3. Get a good marine-grade charger while you're at it. And, also, marine wind generator might be an option, especially if you're on top of a hill or on the shore or if there's a strong dominant wind. When a good wind is blowing they generate a lot more then a solar panel.
4. Try and find a AC/DC power adapter such as the IBM 22P9010 Thinkpad 72W AC/DC Combo Adapter. This will get rid of the huge inefficiency of running the power through an inverter to make AC to then have a transformer turn it back into DC. Note that the watt rating is because this adapter is good with ALL thinkpads.
5. Your lighting will suck more power then your computer anyways, invest in the most power saving DC lighting you can get, see a marine or RV dealer.
6. Pumps (say, for pressurized water) will drain your battery really fast. Air contitioner/heater, electric pipe heater (ie: you use a well that is not under the house and the pipe is not buried deep enough or pump from a lake and you're in a cold climate) will require a genset.
That's what I can think of, on top of my head. Basically, the Marine electricity folks have the most experience with clean DC electrical system, mostly from cruising sailing boats. RVs are also ok but they rely heavily on genset so they get away with 1+ kW/h of consumptions.
Also, when you switch to DC power, what you really want is an amp meter on the main circuit to know just how much you're drawing and a volt-meter on each battery bank(s) to know the charge level.
A marine deep cycle usually provides 90 Amps/Hr. @ ~14VDC nominal for 1 Hr. Full discharge is about 11.5VDC (this would kill a car battery in a few cycles) and full charge is around 15VDC. A 48W constant DC draw @ 12V is 4 Amps/Hr.
- you have daylight
- the river is flowing
- there is a breeze
If all of the above fail, you have 2-8 hours of UPS power (depending on how big and how many UPSs you get), and 2-3 hours of battery in the laptop (make that 4-6 if you get a spare battery). You could make it through a frozen, long, dark, and still Alaskan night with that setup. You'll be set...and still nerdy/* oops I accidentally made a comment, sorry */
I got AC power not long ago but lived thru a couple years of "self generation of household power." I am in the mountains of Colorado. This is a situation where nomenclature such as generators, power inverters, DC to DC converters, solar cells, storage batteries and stuff will soon become everyday terms.
I would suggest that for electronic devices, stay as close to DC as you can, meaning use electronic devices intended for battery power. It is far easier (and safer due to transients) to use solar cells to keep battery systems charged than using inverters powered by generators to power devices.
I suggest going the laptop route and find yourself a local electronic engineer who (like myself) has been this route before.
Enjoy the new place !
TG
If you decide to go the route of the desktop for this project (which is possible, but I still recommend a laptop with DC/DC power adapter) then here is what you need to get:
Start with an ATX or microATX case. If you choose microATX, make sure that it accepts a normal ATX power supply. You can buy DC-DC ATX power supplies online (but microATX ones are harder to find) As long as your microATX case takes the ATX PSU (i have one i bought for $30 online that does just this, I think enlight's microATX also does it) then purchase an ATX DC-DC power supply online. 180 or 200W should be enough. You may also want to consider a Shuttle Cube barebones with nForce2 motherboard. In this case you could probably still use the DC/DC power supply, but you would have to have it sitting external to the unit (in the back somewhere) Maybe paint it black so it doesn't look ugly, or put it in some sort of asthetically pleasing case of your choice.
- Don't go for the highest power CPU and video card. Select either AthlonXP (barton core only), Duron (latest core), Pentium3, or if you can get your hands on it, Pentium M processor. DO NOT buy a pentium 4 or P4 based Celeron you will seriously regret it. the newer AMD AthlonXP Barton cores have very good power saving features and if you don't overclock it, you will not be in so much hurt. In fact, it is possible with newer motherboards to underclock the chip and under volt it. I would definately consider doing this once you get your system up and running for the long run.
- Select a motherboard for your processor. if you are going with athlonXP or duron, I would recommend the nForce2 Ultra motherboard. Get the one with integrated video. You don't want a seperate video card taking up extra power. The integrated video is decent 3D with quality similar to Geforce MX series. NForce2 Ultra's dual channel memory controller should HELP make up for some slowdowns get for having a lower powered/underclocked CPU.
- With the nforce board (or other comparable board) you won't need addon cards like NIC or Sound. (hopefully your motherboard will be supported under linux with sound and NIC drivers) if you do need addon cards, use only your absolute minimum requirements.
- Buy LARGE 5400RPM hard drives. Don't go for 7200RPM, and don't buy small ones. If you want 160 gigs, don't go out and buy 4x 40GB drives. Just buy one. if a RAID array is required, then still try to stick with 5400RPM drives as large as possible. The larger your drive the fewer you will require in your system. Don't use a buncha extra drives you have laying around. Spend extra on this project and do it right with a single drive solution.
- This next step is a little harder to do with commodity equipment, but is possible. Buy fans that will adjust their speed depending on temperature. Most "temperature sensitive" fans are tuned so that in any real world circumstance, they are either full time full speed, or full time minimum speed. You won't find many fans that are tuned so they slow down when your PC sleeps and speed up when the temp rises due to CPU load. You need seperate logic to do such things. The simplest way to go is with a "fan bus" which has manual knobs on the front of the computer. You turn the fans down as low as they go when you get up and leave your PC idle. AVOID fans smaller than 80mm like the plague. Don't put active cooling on your motherboard chipset, insted opt for a larger heatsink on the northbridge, with quality mounting and quality heatsink grease. Also, opt for expensive but massive and large heatsinks for the CPU. Don't even bother with a 60mm heatsink, as it will cost you in the long run. I personally use 80x80mm alpha heatsinks (with copper inlay) with a 92mm fan that has a 92-> 80mm plastic fan "adapter" cone. This way you can buy LOW SPEED 92mm fan that uses negligable electricity rather than buying high powered high speed 60mm fans. Consider using a single 120MM case fan in the front of the PC running at 5 or 7 volts (you can do this by changing the wires on the MO
Two infinite things: your stupidity and mine. But I'm not sure about the latter. If my sig offends you, I'm sorry.
A small system for powering a cabin can be had fairly cheaply - under $5000.00 for a decent system (a very decent system), if you install it yourself. Most of cost will be in the panels and batteries. You won't be able to run a washer/dryer or anything large like that, but if you set up LED lights or compact flourescents, you can have a nice solution for the cabin, to provide lighting, run a small TV or radio, maybe a few small RV/boat appliances (they make appliances specifically for RV's and boats that run off of 12 or 24 volts) - plus a laptop.
If you have steady wind, a small wind generator or two could be handy as well, as long as you are in a clearing or can get it above the treetop level (just make sure to ground it for lightening strikes).
If you just need some quick and cheap power for lighting, a small solar rig can be easily cobbled together from a small panel or two, one or two small old UPS batteries (like the small desktop UPSs use), a diode (for reverse current protection of the panel), and some wire plus a fuse. I built such a small rig to run a flourescent light in my tent at Burning Man this year - ran great at night, charged it during the day - didn't spend a dime on the batteries, the panel was from a yard sale (think I spent $10.00 on it or something).
Reason is the Path to God - Anon
Not a bad idea!
Lets see, you should ideally keep your voltage drop under 5%, and this 250 Watt computer will draw about 2 amps of current.
120V * 95% = 114V, so we need to keep it above 114V, therefore we cant drop more than 6 volts total on the extension cords themselves (or 3 volts per wire, since the current is bidirectional.)
Thats 3V drop per wire at 2 Amps, so resistance of each 79,200 feet of wire should be lower than:
3V / 2A = 1.5 ohms
OK then.. we need three wires, each 79,200 feet and with less than 1.5 ohms per wire. That's 18.9 milliohms per thousand feet. Well, they do make wire that big, but you cant buy it at any Home Depot. So, we'll make the extension cords from the biggest wire you can get at Home Depot. Aluminum 4/0 wire, typically used for 200 amp service entrance condutors.
Unfortunately, using a single cable of 4/0 would drop almost 9 volts in each direction across this long a run at 2 amperes, so we're going to have to use ALL the conductors in an entire four conductor 4/0 cables for EACH conductor of your power cord to get the resistance low enough for your application. That will get us right at the maximum 6 volt drop at 79,200 feet out.
So, we need two 79,200 foot long 4/0 Aluminum SE-R cables, one cable for hot and one for neutral and we'll assume you'll drive a ground bar yourself since you're 15 miles from the 120V receptacle.
I think that cable is about $2.90 a foot last time I looked, so we need $459,360 worth of cabling. Probably best to buy in 1000 foot spools, but then you'll need hundreds of split bolt connectors and miles of electrical tape. (The good kind, not the cheapo electrical tape.)
Anyway, it is doable. Pulling the cable could be a real bitch. And keep in mind you're not allowed to suspend cables from trees anymore according to 2002 NEC. But then, you cant really use SE-R cable as outdoor extension cords, I'm just trying to keep this affordable for you.
Regards
If he's trying to escape the Boy Scouts of America, why is he going out into the woods? The BSA live in the woods! I wonder if there is a merit badge for Open Source Programming yet? Nah, stinky nerd tracking, maybe.
--Mike
You didn't just join a mointain militia, did you?
I lived for eight years without electricity and then about 6 months on an off-the-grid power system. The laptops are definitely better: 1) Yes they take less power which will make a BIG difference. The numbers may not seem like it now, but when you actually get it set up, you may end up going for a few days of rain, clouds, etc. and then your battery bank can bottom out if you have too much to run and heaven knows that the computer is a necessity. 2) For some desktop power supplies you may need a true-sine inverter. Regular inverters that convert from DC to AC make a simulated sine wave out of the electricity, but its really more of a blockish wave. Inverters like the Prosine 1000W are more efficient and will run your desktop if you have the battery juice left, but they cost significantly more. 3) You're going to need that laptop for the car-trip back to civilization.....
If you can't say something nice, make sure you have something heavy to throw.
Check out Ken Kifer's bicycle touring experience with a solar powered laptop.
-biff
I think overall you will like a laptop better. I have some isolated land wo power but use a 12 volt lead/acid battery for my electronic addictions. You can use a marine battery for lots of juice or a smaller battery (deep cycle) for less. A big marine battery will power your place for a day or two and charge up from your car if you just haul it along wherever you go. An inverter to produce 120 vac is convenient.
... if you have to hike a long way in then I think you will still want a laptop but will need solar power to recahrge it. I have found small 12 volt generators w/ 2 cycle engines you might be able to use there to keep a bigger battery charged.
.02 worth
Now
As far as laptop vs desktop I would definitely go with the laptop. I use a 1.2G Celeron laptop and it is very efficient. I kind of like the fact that when the charger is on the screen is brighter so I run it with the charger and eat up the power (still a lot less than a desktop)
just my
I have a "unabomber" shack out in the middle of nowhere, with no utilities to speak of. What you speak of is *very* doable with Solar power.
A few reflections on what I've learned.
* A PC, as you've learned, will usually consume in excess of 100W of power with the monitor on. Using aggressive settings on your power management software, a VIA EPIA motherboard, and a small LCD monitor you could probably get it around 50 watts. Such a machine is likely to feel slow.
* My Apple Powerbook is very solar-friendly. ~15W during heavy use.
* Try to get everything you need built-in. Things like PC Card devices or external storage really suck down power. The built in devices tend to be engineered for better power management profiles.
* If you find yourself needing to network, wire it. Wired networks suck less juice (at all points) than wireless. And it goes a lot faster.
* If you want to listen to music, budget that into your battery system. A laptop playing a huge MP3 playlist is never going to idle the processor down. Luckily batteries are relatively cheap, so adding just one more battery will add several hours to your runtime.
* If your situation is like mine and you will have a lot of little construction projects on your cabin while you're out there, my power use went WAAAY down when I switched from corded power tools to 18V Ryobi cordless tools. Charging the batteries did not appreciably diminish my reserves, the tools were almost as powerful as those they replaced, and they were much quieter and a joy to work with.
* Don't mess with car batteries. They are no good for this application. At the very least, look at RV/Marine Deep Cycle batteries (12V). Better yet, look at 6V Golf Cart batteries (which you pair up in series for 12V). The Golf Cart batteries will be the ones you want during those overcast weeks.
* Look into lighting, appliances, etc. that run directly off of 12VDC. There are many web sites out there that cater to hunting cabins, homesteaders, RV's, etc. You'll pay more for these appliances up front, but it is much more efficient to run most of your day to day stuff off 12VDC as you lose a lot in the inverter going up to 110VAC. The computer, however, should probably run off 110VAC if for no other reason to ensure that you're getting a steady clean feed from the inverter rather than from your PV panels & batteries, which may surge if the clouds suddenly part or what have you (the inverter will buffer this).
Don't be so quick to dismiss wood! Take one 30' coil of steel tubing (auto store), used weed eater two stroke engine, make a bash valve, injector, and condensor (water cooled) and a few hours of lathe and mill work and some brazing. Add a used alternator, and some controls and add a deep cycle battery and a 1000W or so inverter ($100 online). Google will reveal the details. Now a cord of wood will not only keep you warm all winter but also run your PC, lights and a small fridge/freezer. Much more sensible than a solar/wind system :) :(
If I wasn't so dang busy helping my wife get her business off the ground I'd have mine built by now
90% of the wealth is in 2% of the pockets. Bummer to be in the majority.
One thing you should probably think about, particularly considering your means of generating power (solar), is how you're going to jack this thing into your power system. You'll probably want a transformer to have some AC power in this cabin, but that's an extraordinarily inefficient way of using electricity.
If you go with a desktop computer, the power supply is going to expect AC input. The laptop, on the other hand, is going to have a power brick and a DC jack on the laptop.
For optimum power efficiency, you should get a laptop and then buy a 12V regulator, and a car-lighter type plug. The wattage is important, in terms of power consumption, but the voltage is equally so.
The HP/Compaq laptop we use onboard (its a ze1210, which is a basic consumer model of a year or so vintage -- runs Athlon with PowerNow). Using the DC adapter, the strain on the ship's battery is noticable, but not huge -- much less than the radar, for instance. When we run it off of one of our AC plugs (we only have one, and we almost *never* use it, the transformer usually stays disconnected), its a huge power drain -- more so than our radar array.
So, definately a laptop. Wire your cabin for DC. And consider looking at boating technology guides in general. They probably most closely approximate what you're trying to do.
-Shylock
Statistically speaking, there's a 99.998% chance that my IQ is higher than yours. Get over it.
This is a no brainer. Go with a laptop. Laptops are designed to use minimal power. Mine only consumes 75W max from the wall. Much less if it's not charging a bettery, backlight turned down, not burning a CD, etc. Use a wired net connection since wireless cards use a lot of power. Don't forget if your power browns out or fails you're still golden if your battery is charged.
Some numbers behind Kriston's post.
The "highly efficient" Luxeon star white led will produce a mighty 25lumens/watt.
A boring hardware store compact flourescent will produce 55lumens/watt or better.
Some questions:
1: How long will you be in "the boonies"
2: Is Internet connectivity a necessity, or nicety?
2a: Is dial-up satisfactory?
3: Can battery or otherwise low-wattage/DC solutions do the job, or do you need AC power?
If you take into consideration that you'll be in an apparently stripped-down environment, you might be happier and more productive in the long run if you have a stripped-down computer to match. I lived in the country with a radically altered computer situation, with 28.8 the absolute BEST I could do, without springing for ISDN, and I found that a powerful PDA - as long as it had a typeable surface was enough to suit my needs. However, I didn't need to compile anything, host any databases, or do any kind of "9 to 5" (as you mention) thing with that setup.
Diesel (generator) is a great idea. Is it practical for your situation? Solar is also a worthy power factor to consider, but not starting in January :), nor February, and questionably March, as well. Pedal-power works in any light condition, and since you're in the country, your access to citified diversion is limited as well, so maybe a little treadmill or excercycle computing would probably benefit you. (As it would any geek!!
My suggestions:
8/16 Bit Wonder of your choice & TV (portable, handheld, console, whatever - can be modified to run on straight DC)
2nd/3rd Generation Palm/WinCE Device
Apple Newton 130 or eMate 300 at minimum,preferably 2100/2000U (WiFi/MP3/web server/etc. capability plus EXCELLENT power usage)
Psion or compatible device (Has keyboard and multi-tone display)
Modern, power-concious laptop (used Transmeta-powered devices are in the stream, now)
Standard, off the shelf laptop. IBM or Toshiba, if you're going to be out there for a while! (Maybe a Toughbook?)
I dunno.