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Wireless Internet In An Off-Grid House
matt20 writes "This is an interesting article of a family living off-grid using solar panels. In such a setting, every watt adds up. The typical home computer and monitor use almost 150 watts. What is the best computer arrangement in such a setting? Here is what worked best for them. Anyone know what percent of our national power is used on computers? Should we be thinking wireless on laptops?" Even on-grid, this article raises some good points about power consumption and convenience.
With the number of devices in the home that now use DC power, I always thought it might save energy to have one large AC to DC transformer for the house, rather than having "wall wart" adapters for each device. Even when the device is off that wall wart is using energy(feel it, it's always warm). Why not have a more advanced transformer that could adjust for load, and run DC through wires to the whole house. Plus, no more problems trying to plug 2 wall warts into adjacent spots on a power strip!
This is why FM and TV broadcasting uses multiple-bay antennas... even the omni-directional ones. By directing less energy straight up (who lives _above_ a tower?!) and less energy straight down (who lives directly under a tower?!) they can send more energy out horizontally, extending their range. The same applies to wireless networking, just that it's at a higher frequency... and thus even more directional.
-T
recently my local news had a story about a household that used solar. they actually sell their excess to the electric company, to the tune of something like $300 a month. apparently it paid off the equipment in about two years, and now they just collect as profit!
The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
Anyone know what percent of our national power is used on computers?
Judging by the unavailability of this site, I'd say not nearly enough.
Is your browser retarded?
Efficient Computing & Wireless Internet
x b,00.asp
p n=2&s=1005&a= 24385&ap=1,00.asp This is an article at the Extreme Tech site and may be available for a limited time.
©2002 John Bertrand
A year ago, when we finally settled into our still incomplete solar powered house, we set up our trusty three-year-old computer. Then, having no landlines (electricity or telephone) we installed a wireless broadband Internet connection. So we were sitting pretty, right? Wrong.
In fifteen years of home computer use, we have never just left the computer on all day. But times and uses have changed. Our computer has become more and more of an appliance rather than a specialty tool. In our new home, it became apparent that we needed it available constantly for Internet research and e-mail. Yet leaving the system on, even in sleep mode, used too much energy. Our fairly typical desktop system draws 180 to 190 watts.
Flipping it off and on was too much of a hassle because of the almost 2 minute boot up each time we needed to check something. Besides, even turning it on and off as needed was a serious drain on our 1.2 KW PV system. Expanding our PV array (sixteen, 77 watt modules) was not an option because the present rack and wiring are maxxed out, not to mention the hassle of having to submit a new electrical permit application, complete with engineering stamp.
The Search
So I began researching notebook computers. Without a doubt, they would provide a much better energy use scenario. I wanted the lowest possible energy use in a quality unit.
I have always purchased desktop systems from smaller companies that offer good quality parts for the money. I could always make changes later if necessary. But notebooks are a different animal, since they are more or less a closed package. So it is very important that it has all the functions you will need.
For many people, the notebook can replace the desktop unit. So a 14 or 15 inch (36 or 38 cm) screen, 5 to 7 pound (2Ð3 kg) "desktop replacement" machine will work. For others, a really lightweight 3 to 4 pound (1.4Ð1.8 kg) unit with a 10 to 12 inch (25Ð30 cm) screen is fine, since the desktop unit is not being displaced, but supplemented and networked. The former will certainly save watts over a desktop unit, but with its built-in drives and large screen, will use considerably more energy than the latter.
For us, keeping the desktop unit for graphics-intensive tasks seemed desirable, since the screen is larger, and CRT monitors generally handle graphics better. So I researched what was available in the smallest of the Windows-based notebooks.
Our personal parameters included finding a highly rated, quality product from a well-known company (such as Dell, IBM, Gateway, Micron, Sony), long battery life, no built-in drives other than the hard drive (but with an attachable CD/DVD drive for loading programs, etc.), at least 256 MB RAM and a 20 GB hard drive, a touchpad pointing device, and a high quality graphics card that will not drop frames when playing a DVD movie.
I began looking more than six months ago. Because of their customer satisfaction record, I was somewhat predisposed to look most seriously at the Dell offerings, in particular the Latitude L-400. But it was weak on graphics and, having been on the market quite awhile, was not tops in energy efficiency. We came close to trying a Sony unit available from Costco for less than US$1,000, but it only had a 10.4 inch (26.4 cm) screen, older chip sets, and mediocre graphics. That finally kept it out of the running.
A Small Gem
In November 2001, Dell introduced a new model, the Latitude C-400. It was much like the earlier L-400, but had updated processors (866 MHz or 1.2 GHz, running on half a watt), a new generation of energy-saving Intel support chips (830M), graphics adequate for DVD movies, both a touchpad and a pointing stick, and some other goodies I found desirable.
I watched the prices, including the Dell "refurbished" units. In January, after the Christmas rush was over, I kept close track and finally bit on a good offer. (Remember, if you buy on the phone rather than off the Net, you may be able to negotiate for even better than the current sale prices, but beware of the frustrating sales-speak even from reputable firms.)
This particular model best met our needs. The US$2,300 price is in the midranges, with basic economy models available around US$1,000, and corporate road-warrior models well above US$3,000. (Note: laptop prices continue to fall, so you may be able to do even better by the time you read this.)
In terms of energy usage, though, this model has to be near the lower limit. We measured usage with a Watts up? meter. The meter isn't extremely accurate when measuring loads drawing less than 20 watts, but it's close enough for general use. In any case, the C-400 uses just 15 to 18 watts when in regular use.
This figure, when compared to the desktop system, is cause enough for joy. But when we close the case, putting the system in standby (it goes to hibernation in 15 minutes, or whatever you want to set), the usage is too low to measure with this meter.
Wireless Internet
When it comes to broadband Internet service, there are three major routes and one minor route. Leading the charge these days is cable modem service from the cable TV companies. This is followed closely by DSL (digital subscriber line) service from the telephone companies. Satellite service from the two satellite TV companies has made inroads mainly where the other two services are not available.
Finally, in a few areas, ISPs have established fixed wireless service, which uses a line-of-sight radio link between their operation and subscribers. The radio signal is in the same frequency range as a microwave oven, and can be fairly characterized as a "microwave link." It conforms to the IEEE 802.11b standard used for wireless networking within the home or office, and is theoretically capable of 11 MB per second information transfer. A radio transceiver and small antenna are required.
We had a choice of going to Starband satellite service or Interlink Hawaii (local ISP) fixed wireless service. Starband was just becoming available with no track record, high upfront costs of more than US$1,500 (installation is less expensive in the continental U.S.) and a monthly cost of US$70. Interlink's fixed wireless service had been around for several years, had an installation package of US$500, and cost US$50 a month. Needless to say we went with the latter, which uses a Breezenet Pro.11 radio.
Overall, we have been very satisfied with the service. When our radio was failing after less than a year (it is leased and was used), they were slow to replace it. But otherwise, we have had mostly speedy surfing, with very little downtime. And being a local company, they are usually easy to work with. Power draw of the wireless system is 1 to 2 watts.
Over a typical day of turning the system on first thing in the morning, using it for about 5 hours off and on, with it in standby or hibernation the rest of the time (about 7 to 8 hours), the total watt-hours used is 84. That's equivalent to about 25 minutes use of the desktop system! If it is on standby, the C-400 comes back to full use in a few seconds. From hibernation, it takes all of about 15 seconds. That's very tolerable for an appliance.
Other Considerations
As a selling feature, notebook manufacturers try to maximize battery life, that is, the amount of time their computers will run on a single charge. Since we keep the unit plugged in so much, battery life is not critical, but it's still a good indicator of system efficiency.
Within groups of similar computers, the longer the--battery life, the more efficient the computer is. This comparison works best if independently measured, but manufacturers' estimated time is usually a good rough estimate. Just remember that this measurement applies within a given category of processor, screen size, battery size, and peripherals.
While it may seem good to keep the battery charged up, it is also good to let it cycle some. So don't leave it plugged in all the time. Unplug it every once in a while, and let it discharge fully before charging again. If NiCd is used, the battery should be fully discharged routinely (several times a month) and then refilled. If the battery is NiMH or lithium technology, it isn't as important to fully discharge the battery routinely, but it should be fully discharged once every month or two. Most modern notebooks use the NiMH or lithium ion batteries.
Keyboards are also a concern with notebooks. The great portability of a 3+ pound (1.4+ kg) unit is somewhat offset by a slightly smaller keyboard, not to mention a few keys in somewhat different places. I find the tradeoff to be acceptable. You may not. The larger notebooks do have equivalent keyboards, but not exactly ergonomically correct ones.
Another alternative is to buy a notebook with an auxiliary keyboard port. Then you can use a standard keyboard ordinarily used with a desktop unit. Most larger notebooks have similar ports for a mouse and monitor. Others have auxiliary ports in docking stations so a notebook can emulate a desktop computer.
Of course, not everyone is in a position to part with more than US$2,000 to save some watt-hours. But it was worth it for us. The cost of adding more PVs and related equipment to have our desktop unit available full time would have exceeded what we spent. Almost any notebook computer, with the ability to handle similar tasks, is far preferable to a desktop system for energy conservation.
As time goes on, more models will use the new energy-saving chip sets. Even the model we bought is now available as refurbished. (Usually they are returned within 30 days after purchase and like new.) I just saw one similar to ours for less than US$1,600.
Although I was researching PCs, Apple's latest notebooks are also quite frugal. I managed to get permission (not without a questioning look from the store manager) to measure one of the 600 MHz G3 iBooks, and it came in at around 20 watts.
Dessert
The rest of the changes to our computing scene may seem frivolous. Still, if we see the computer as an appliance, the handier the better. We added a D-Link wireless router (Model DI 713P, US$140, 7 watts) that gives us the ability to use the laptop almost anywhere in the house. It also connects the two computers together and provides good Internet security from hackers. (Incidentally, software can provide good protection also, but it's not as good as the hardware solution in a router.)
The setup of the router was very time consuming. I have read of others who have had an easier setup, and still others who have given up and returned the unit. So I have mixed feelings about it. Setting up a single computer would be easier, as would setting up with only a newer operating system.
The manufacturers need to provide more information than we received. Usually I like to exhaust my own resources before calling tech support, but I still spent quite a few hours sorting things out with both the router tech support and my Internet service provider tech support.
Energy-Sipping Computing
Everything needs to be on switched outlets for efficiency, preferably surge protected outlets. On one switch, we have the fixed wireless radio and the router, which have no internal switches, and the printer, which does have an internal switch (usually turned off). The notebook computer is on another, and the desktop computer and scanner (usually turned off) on another. So we can handle almost any combination of computing needs without having unnecessary equipment sucking electricity.
In spite of the less-than-satisfactory router experience, our new computer system has been a great convenience. After half a year of no computer availability in our off-grid home, we learned that our desktop computer was just too much of an energy hog to work for us in our limited-energy environment. Having cast about for a solution, I believe we found a good one with our 3 pound (1.4 kg) notebook computer. It draws only 15 to 18 watts when being used, and practically none when in standby.
We no longer have to feel guilty when using a very important appliance. It is handy anywhere we are in the house, anytime we need it. And so far, we have run the generator hardly at all. Aloha.
Access
John Bertrand, PO Box 811, Holualoa, HI 96725 caber@kona.net
Dell Computer Corporation, One Dell Way, Round Rock, TX 78682 800-915-3355 or 512-338-4400 csd@dell.com www.dell.com Dell Latitude C-400 notebook computer
Alvarion, Inc., 5858 Edison Pl., Carlsbad, CA 92008 760-517-3100 Fax: 760-517-3200 sales-north.america@alvarion.com www.alvarion.com Breezenet Pro.11 radio
D-Link U.S.A., 53 Discovery Dr., Irvine, CA 92618 800-326-1688 Fax: 949-753-7033 sales@dlink.com www.dlink.com D-Link DI-713P wireless router
Some Useful PC Computer Web Sites
Major Notebook Manufacturers:
www.dell.com www.gateway.com www.ibm.com www.micronpc.com www.sonystyle.com www.hp.com www.apple.com
Networking Info:
www.wown.com www.pcworld.com/features/article/0,aid,86935,tk,c
Internet Security Software:
www.zonelabs.com Zonelabs' Zone Alarm is a free download; the Pro version costs US$40. The free version has been highly recommended and has been used by the author. The Pro version has more bells & whistles.
Notebook Power Management:
www.extremetech.com/article/0,3396,a
Evaluations & Comparisons:
www.pcmagazine.com www.zdnet.com www.techtv.com www.pcworld.com www.practicallynetworked.com
Shopping/Price Comparisons:
www.pricewatch.com www.pricegrabber.com www.techbargains.com www.amazon.com www.cnet.com
I don't know the number, but the trend is disturbing. I would have naively thought that as
- computers get more and more computational power
- while their power requirements per computational power decrease
that the number of computers needed would decrease. Instead, the number of computers seem to be multiplying. Even I'm guilty of it; add a firewall here, add a web server there, add a NAS box in the room.I do appreciate your desire for a low-power consumption box. And I do appreciate that your computing solution only involves a single box. Good luck in your search.
3) Consider replacing your Athlon Windows XP machine with a 386/33 with 4MB of RAM, running Linux of course.
4) Better yet, replace your computer altogether with an abacus.
5) Don't use a hard drive : They wastefully spins all the time the system is on. Stick with a 3 1/2" (or 5 1/4") floppy disk drive.
6) This one is a big one, but many people are not aware of it: Each incoming bit cumulates power into your system, to the point that a fast incoming stream with minimal outgoing can actually power your system purely by the internet connection. This is a tremendous power saving (or even GENERATING) tip: Go onto IRC into some of the hackers, and threaten those bisnatchis that you have a tremendous connection, and they can't possibly DOS you, etc. Soon they'll have all their clients ping you, and you'll be literally soaking up the wattage packaged bits. If you can keep this going overnight, your computer will actually start feeding power into your houses grid (MAKE SURE IT CAN HANDLE THIS! You may need a flux capacitor to ensure that it can modulate and store the excess).
For those unfamiliar with Home Power, this is a typical article from them. Their typical monthly magazine has an article about "Solar Guirrilas", or people who decide to put up solar panels, plug them into the "grid" (municipal power supply) and not get the permits for it. They also toss in a "I use solar panels and/or a wind turbine to make 10-100% of my own power, using/shunning batteries in the process" article that makes one think that such a thing is so great, why doesn't everybody do it? (The answer is in a very attractive tabular form that has a dollar figure at the bottom.) Recently, although I don't think it's always, they have had an article on how easy it is to convert your existing car to an electric one. As near as I can tell, it's a thinly veilled advertisement for one of their sponsors (and possibly an editor, sheesh I wish I remembered why I suspected that).
Okay, cynicism aside, because that's what slashdot's all about, Home Power is actually one of my favorite magazines. They help me think about what I can do in my day to day life that may have an impact on the environment. I'm not likely to blow $20k on solar panels on my roof, not likely to get a wind turbine that always needs maintenance during the worst times even after I get approval from my homeowner's association, and I'm not even likely to convert my car into a $3k worth of batteries beast that maxes out at 65mph. I did, however, convert all my light bulbs to fluorescent and blew the $20 on the programmable thermostats. I'm even considering one of those insulating spreads that you wrap around the water heaters. Now if I could blow $4k on my car and make it a battery driven beast that could handke 85 as I commute down Parmer Lane in Austin...
I dream of, one day when I'm rich off of my wife's stock options, building a house with solar panels on the roof and maybe a pretty, whirring wind turbine in the back yard while I contribute to urban sprawl.
To pre-emptively strike against a good slashdot myth, yes, solar panels will pay for themselves. They earn back the energy that it took to make them (and start to net negative CO2) after 1-3 years of operation, depending on if you're in California/Arizona or Vermont, and if you ignore the time value of money, can earn their dollar cost back in 10-20 years, depending on costs, location and care.
I can't load the article, but from the copy and paste here, it doesn't appear to say which one he got (he just mentions apple's iBook as the last machine he looked at).
I also just checked, and apples flat screen iMac has a max of 130watt power draw, which is quite impressive for a low power usage situation. I'm glad my college bought those to replace the macs, to counter balance the P4's they are putting in (in terms of power consumption).
Hardly. Buying your energy from a nuclear power plant will never net YOU, a homeowner, a net profit. Maybe if you live in the town that houses one you'll see something from their tax money.
;) But it does frequently exist, and a net zero or close to it for energy manufactured from a clean and renewable resource, for many, is maybe worth forgoing marble countertops.
If you aren't actually OFF the grid, most areas have a net metering program where you can sell excess power to the grid during the day and buy back power at night. This eliminates all the battery banks, a substantial chunk of the cost. If you furthermore design a home to be energy efficient to begin with, you can have an "affordable' solar system. I use quotes as it is undeniably a greater up front cost, but there is a return, though admittedly not much and it takes awhile to accrue.
If you ARE off the grid, then many people go with solar simply based on the economics of having a power line run to your home, if one doesn't already exist, can very quickly outstrip the cost of an entire solar electric system.
And for $1000 US or less, you can get solar hot water collection to at least augment your domestic hot water needs as well, with a definite payback period of less than ten years.
Not that payback is currently the best reason to go with solar. If someone hits a baseball into your panels, there goes your chance of payback for awhile
Interesting that I routinely deal with homes that will think nothing of spending thousands upon thousands of dollars to use Antique Jerusalem Stone on the floors, but mention Solar and the first question is, "what's the payback".
ok, someone explain this to me. For a site to get slashdotted, slashdot readers would need to click through to read the articles...but as a long-time slashdot reader, I know that nobody here actually reads the articles, so...what's really taking down all these web servers?
We did a study for one of my engineering classes recently about the power required to produce a solar panel as compared with the amount of power produced over the panel's lifetime. Turns out that manufacturing requires nearly 40% of the power the cell will produce over its lifetime. Kinda makes you want to look elsewhere, eh?
Photovoltaic cells have moved along from the 3 to 5 percent efficiencies of years past, although not by a large amount. A student made a presentation at my college's undergraduate symposium in the spring, and I believe he reported current efficiency standards of around 18%, with experimental (i.e. costly) cells being able to achieve rates of around 30%. I didn't get the chance to ask the student why the rates were so low, but I would assume it has to do with the design, materials, etc. I think the big jump from the ~5% range to the +10% range was due to the use of a different material (or combination of materials) - involving silicon I believe. Another thing to remember when looking at statistic on solar energy received by Earth is that although an extremely large amount of energy comes from the Sun and hits Earth, only a small amount filters through the atmosphere to a level where we can harness (i.e. near the Earth's surface to be used by photovoltaic cells). I think I recall a theoretical physicist talking about humans placing energy collectors near the Sun, in the future, that could provide all the energy we need, and that the collectors would actually be fairly small - somewhere on the order of several thousand square kilometers or something. Anyhoo, I'm sure you can find a lot more exact info with a few google searches, just adding what I recall.
I think the problem with current solar cells is they are hard to produce and less than efficient.
I had a dream the other day about algea that could convert solar energy into electrical energy. I envisioned giant ponds of green murky water with evenly spaced rods to collect the electricity the little buggers give off.
It's probably just a pipe dream, but considering our current biotech and genetic technology, is electricity producing algea possible? I mean we already have algea (or was it bacteria?) that live off of sulpher given off by thermal stacks deep below our oceans.
Consider this...
You can see the crystals on a solar panel with the naked eye. Very large, sort of wasteful. Can you see a single celled organism with the naked eye? Theoretically you could pack a whole lot more algea into a square inch that you could solar crystals.
This is just a question, it's been buggin me for the last few weeks, and if anyone has an answer please share.
--toq
my parents recently wired their home to use solar panels
the house itself didn't actually get converted over, however
all that was needed to allow normal function was an inverter
it converts the dc to normal line voltage
the excess power is pushed back onto the grid and due to recent legislation, they get paid for it
needless to say, the electric bill is down tremendously...
Base 2 yields only ARTIFICIAL Intelligence
Answering the originator's question about how much power is consumed by computers and the like, we did a study for DoE last year. Note that it excludes home computers, focusing on business use, but this picks up the bulk of power consumption. NTIS.gov will sell you a CDR of report PB2002-101438 for $47. A PDF slide set summary is available at:
http://www.tiax.biz/pdf/EIA-OffTelecom-TIAX.pdf
One interesting conclusion:
Commercial Office and Telecommunications equipment electricity consumption represents just under 3% of national electricity consumption, and a little over 1% of national energy consumption.
Note that the report was prepared by Arthur D Little Inc.; TIAX acquired the group that did this study.
Get a laptop and several batteries. plug the laptop in to power anywhere you can... hotels, friends houses, offices, wherever! charge up all your batteries and you're good to go. two batteries could be easily charged up throughout a day's use at the office and friend's houses. and one lasts for at least 3 hours. Weekends would be difficult, as would long programming runs.
Oh shit! I forgot to click "Post Anonymously"...
You mention 150 watts as if it's a large number.
Some rough figures:
Room with 3 incandescent lightbulbs: ~180 watts
32" television: ~250 watts
Microwave: 1000-1500 watts
Stove: ~2000 watts
Oven: ~3000+ watts
Window A/C unit: 750-1250 watts
Central A/C for a 2000 sq. foot house: ~5000 watts
Central A/C for a 4000 sq. foot house: ~9000 watts
So running your computer 24 hours a day would take approximately as much power as running your central A/C for maybe 20-30 mins/day. If you live in a hot climate, raising the temperature on your thermostat by 1 or 2 degrees is going to save you more power than getting rid of the computer entirely. And certainly much more than shaving 20-50 watts off your computer's power usage by using "low-power" components.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Many of Apple's computers give off little enough heat that they do not require cooling fans, and those that do have fans still run cooler than most PCs. I would guess that this means they consume less power than most PCs (less heat coming out = less power going in, yes?). I'd also guess that the PowerPC being RISC rather than CISC helps a bit; that should mean the processor is less complicated and more efficient.
As someone else pointed out, LCD displays consume less power than CRTs.
Would not a G4 iMac then be perfect for this situation?
$x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
$x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
I grew up in a 12v DC household.
We had a bank of half a dozen (or more, it varied) old automotive batteries in parallel which were charged by an old (1919) DelcoLite generator whose original 36v coil had been rewired to produce 18v. We ran it below optimal RPM's to get about 14v. It had sat in a field for 30 years used for target practice before we got it and rebuilt it with an air-compressor piston (connecting rod cut and extended with a pair of bolts welded onto it), an aluminum pot with the bottom bashed out of it as an air duct for the head, a Land Rover instrument panel, and an old motorcycle carburetor. We primed it with gas but it actually ran off kerosene.
We could run for about a week between charges until we got solar and then we only cranked up the generator about every 6 months or so when the cloud-cover had been too heavy.
All lights were ordinary 60w bulbs but anything with a motor was either designed for RV's or rewired. (Fridge was kerosene then butane).
All computer equipment was laptops and portable printers (12v or less).
I made a few bucks on the side for quite some time designing 12v adaptors for laptops that took more or less than 12v and making them fit inside in whatever space the manufacturer had left over!
The soldering iron I used for this was a piece of broomstick and a twist of coat-hanger wire holding a real soldering-iron tip which was wrapped in a heating element salvaged from an incubator.
And I really did have to walk/hitch-hike 20 miles to school every day in the pouring rain (or boiling sun)!
But that's another story...
Linksys PCMCIA 10/100 ethernet card
Power:
5V 260mA, 60mA sleep mode
3V 180mA, 30mA sleep mode
Linksys PCMCIA 802.11b wireless card
Power:
5V or 3.3V
275mA TX, 225mA RX, 20mA standby
Or to put it simply, when operating, the wireless card operates at up to double the power requirements of the wired interface, while giving a maximum of 1/10th the speed. (That's a very optimistic maximum, as well.) There are a few added power drains for wired networks, such as powered hubs and switches, but I'd have to go with the wired net, every time.
In the stupider days of my youth, I was disassembling a phone that was still hooked up. I was holding the piezo ringer element between my thumb and forefinger when it rang - for a full second, my entire body was buzzing, and I absolutely could not let go.
When I was finally able to rip my skin from the piezo, a very clear thumbprint was burned into the thin metal.
Moral of the story: Don't play with phone network devices while they're still plugged in...
Indeed you could... the hard part is storing enough energy for a few hours with small enough loss/expense to to profitable.
:)
There's a plant at the twin lakes resivoir which pumps water uphill at night and generates power during the day.
They have much nicer bathrooms than are avaliable at the nearby national forest campsite, too
--
Benjamin Coates
Recently, although I don't think it's always, they have had an article on how easy it is to convert your existing car to an electric one.
I've spoken to a few people that have done it, and are very happy with the result. They are faster than conventional cars, apparently because the electric motors give more torque. Here is one home conversion that does 100mph and cost £6,000 to convert. Running cost works out at £0.018 per mile.
I'm not likely to blow $20k on solar panels on my roof
Expect prices to drop. There are companies like BP pouring millions into research. Current solar technology is maxing out around 20% effecient, and uses rather nasty substances to make, so the hunt is on for alternative fabrication materials and methods (eg here).
I did, however, convert all my light bulbs to fluorescent
There are new energy efficient light bulbs that run on under 20 watts, are blindingly bright, but best of all now cost less than (afaicr) a couple of quid.
I'm even considering one of those insulating spreads that you wrap around the water heaters.
Essential. Also look out for micro-CHP coming soon (CHP = Combined Heat and Power). CHP is in wide use today in large buildings. Converting electricity to heat or vice versa is very inefficient, and you can get a max of 40% return. By producing both at the same time, you can get 90% return on the energy you put in.
Phillip.
Property for sale in Nice, France
Approximately 1 in 10,000 households and businesses in the US get their power from people other than their local government-approved grid. Given a population of 260 million, and assuming that one household or business exists for every 2 people, that's 13000 establishments within the US that aren't giving us money!
Now, since if these people would probably chew through $10,000 per year in electricity. That's $130,000,000 that ends up in other people's pockets!
The sky is falling on this industry and we need laws to prevent this!
In an off grid home, due to the fact the system mentioned in the article has a rating of 1.2KW, most items on your list of energy hogs are not supported.
In an off grid situation, the stove, water heater, and central heat are not electric. Most off grid homes do have a TV and Microwave. They are simply not on for extended periods. My parents RV is designed to be "off grid" It has 800 watts of panels and a 2 kw inverter with a 60 AH battery. The fridge (7 cu ft) is an energy effecient model. None of the lighting is incandecent. The heating and cooking is all gas except for the microwave. They often will park by a favorite lake somewhere for a week and not have to run a generator. They do have a gas generator for the few dog days of summer to run the AC, but running that is rare due to the high cost of operation.
The truth shall set you free!
Enron inspired my wife and I to have a 2.3kW grid-tied solar system installed on our San Jose,CA roof in Feb 2002. We entered a Net Metering contract with PG&E, such that we are only billed once a year, and our electric meter is a time-of-use meter that permits us to be charged less for off-peak usage. Our excess energy is fed onto the grid, thereby running our meter backwards most days during peak billing hours. Most of our consumption is off-peak, therefore we mostly sell energy at a higher billing rate than that at which we buy it back.
We had already installed a setback thermostat, replaced incandescent bulbs with CFL's, replaced a desktop CRT with LCD display and do most food reheating in a microwave. Our desktop is a Mac G4, which uses less energy than an equivalent desktop Pentium due to the nature of the Pentium chip set, and our other computers are Mac laptops, which are very efficient. No wall warts or other gear are left on when unused in our house. [ Note also that with any type of computer gear, all else being equal, the faster the clock rate, the higher the energy consumption, and the more waste heat that has to be dissipated somehow. If you don't like throwing your money away, for any given task use the slowest "suitable" system. No one should ever need 1.4GHz clock and DDR RAM to compose a text message! ]
The net result is that we will likely generate >100% of our electric needs in an average year, despite our electric stove, and using one or more computers and a TV or Stereo every evening. The installation has a 20 year warranty and will pay itself back in 15-20 years, unlike *any* other toy that I've ever purchased. No, it's not for everyone, and you have to take a long view to justify the expense, but it is quite practical in a reasonable climate, particularly if you have a more or less south facing roof.
Art
The "ideal" goal of any consumer products manufacture would be to list their device as having the lowest power draw so that you can plug as many of these devices into a single wall outlet. However, there is nothing in the spec preventing a manufacture from placing a higher current DRAW on the rating plate as it does not increase the fire risk to the consumer. OTOH, they must be able to DELIVER the power output on the rating plate. Of course, the more you draw the more likely you'll shorten the life of the product ( and see higher ripple if it's a power supply).
Now that's ideal, the truth about PC power supplies is that most of them are cheep pieces of junk. Unless you are willing to pay several hundred dollars for a 300W AT power supply do expect them to really live up to your expectations.
So, to the point of what your system is using, on average, is probably a small fraction of what is on the rating plates. If you average is even close to half the rating plates I expect that you are going to see high failure rates on consumer products. It's just not designed for that level of average usage. The only real way to measure usage is to measure the usage with a meter. And measuring AC power usage is a whole course in school. The simple answer is to find a quality RMS logger and a good meter, at least a Fluke 83 (probably better), to measure peak usage.
Same for running low on battery power. You can safely run the battery to exhaustion, then go find an outlet, plug in and hit the boot button. The machine will come back up exactly where it went down, all applications still running, without missing a keystroke. No lie.
And, the white iBook is *tough*. I've dropped it off a table onto an indoor/outdoor carpeted floor. The CDROM door popped open, but no crash or other permanent damage.
These features are what Apple should be hyping, not the "megahertz myth".
To a Lisp hacker, XML is S-expressions in drag.
Coolness factors, nifty things, and enjoyment, are what life is for. They are the whole reason that the financial bottom line matters at all: so that you will have money for spending on geeky things.
Solar panels are romantic.
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