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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."
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.
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.
A Pentium M laptop with long battery life would be a good choice for its low-power consumption.
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
I've been that far into the boonies, and therefore can tell you you don't know what you're talking about. An axe and a box of matches is still a good idea, but a PC is also a good one. When you are that far afield, a computer with a net connection of some sort is one of the best communication mediums out there.
...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 ----
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.
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
or, he could get an iBook, which i normally get 5-6hrs out of w/ one battery.
just pointing that out.
You said "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."
Considering a 1000 VA UPS costs about $600 in my area and is only rated to operate for about 20 minutes, a 50W laptop would probably only operate for about 6 or so hours on it. For $200 you could buy a car battery (50 A-hrs at 12V), a battery charger, and a 100W inverter and operate for over 10 hours. Or a cheaper solution that I use is to get an emergency jump start kit (mine is 18 A-hr at 12V), and a cheap inverter. For less than $100 I have an extra 5 hrs of laptop time.
You also said: "Now... how exactly are you going to get on the net? Satellite? Pigeon?"
Fortunately, RFC 2549 exists for just this problem.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
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 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
I spent years living in a place like that. It didn't impede my programming at all. In fact, I believe it improved my software design skills, by forcing me to figure out exactly what I wanted before I sat down to write it.
I think the laptop would be the better idea. Gasoline is costly. If you could get one with a seperate battery charger, and get two or more batteries, you could leave the used batteries to charge at a friend's house or your work and swap them whenever you're out. I have uncertainties about being able to use the solar power for your laptop, depending on your setup.
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...
"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..."
For the laptop, they sell 12vDC->DC converters in most retail stores. buy.com and bestbuy both sell them. They come with interchangeable plugs where you can fit any model laptop onto it. Be sure to check compatability of the power adapter with yoru laptop before purchase.
As for LCD monitors, most also have external AC Adapters. All you need to do is find out what pin does what in the power connector. Then buy an approprieately speced DC->DC converter (just like the one for the laptop) and you might have to cut and splice the connector yourself.
unless the LCD monitor has an integrated AC Adapter (like the viewsonic VP171B) then this trick will work provided you are technically inclined to sort out which pins provide which voltages and how many amps each one requires minimum.
Please don't underestimate the power savings from going DC only. As long as you keep your main power lines high quality and short (from the solar pannel to your batteries, and from batteries to devices) then DC power can cut your solar pannel requirements down by 30-50%.
Two infinite things: your stupidity and mine. But I'm not sure about the latter. If my sig offends you, I'm sorry.
Let's put it this way. Running a gasoline generator 12 hours a day ran runs about $500 / month where a normal power bill is $75.
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 also suggest that you look at using only compact flouresent lamps for lighting.
Skip that, go straight for the replacement: White LEDs. A little more upfront cost, but lower power yet, and a longer life.
Why must everyone here be so high-tech? Lanterns, oil lamps, candles, etc. are inexpensive up-front, produce adequate light (at least for my liking), provide a perfect romantic atmosphere (as if most slashdotters know/care anything about that), and don't require electricity. Don't put 'em right next to a curtain or directly under overhanging wood and you'll be fine.
No, but it will be modded to +4, despite the fact that it is a really bad joke. I suppose there is no accounting for bad taste in a world without RTFA. ;P
I have no regrets, this is the only path.
My whole life has been "UNLIMITED BLADE WORKS"
It all, of course, depends on what you want to do. For the occasional weekend the atmosphere and set-up cost of fire-based light is great. For extended periods the cost of replacements and shipping (and the variable quality of the light, even with a good lantern) mean that even a standard electric bulb is cheaper and easier to use.
Florescent bulbs are a proven, mature tech, that work well. White LEDs are newer, with the costs of bleeding edge tech, but offer longer useful life and more flexible installation. If the submitter is planing on living in his remote home either would be worth a look. If he just visits then candles and lanterns may be all needs and his best solution. Any of these choices are worth considering over a standard incandescent: They offer no advantages over the newer tech, and all the disadvantages you pointed out.
'Sensible' is a curse word.