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Keeping Computers (And People) Warm In Winter?
Grimwiz writes "Similar to a few of you, I have some of my computers on a UPS. However, the UK press have recently been warning that power supply interruptions are likely this winter and I've been pondering about upgrading my power protection from those few machines to include a few key house components. In particular, I need to ensure that the gas-powered (but electrically controlled) central heating stays working. I have reviewed a few solutions, including Solar / Photovoltaic or purchasing a generator
but they seem to be hugely more expensive than my simple UPS solution, although they do provide a much longer lasting solution than running off batteries. (A battery solution becomes quite expensive if I require more than an hours backup.)
My power requirements for a quiescent house is about 4amps @ 250V, and I'd like to survive at least 8 hours. What solutions do you recommend?"
A warm jacket.
porn keeps me warm in the winter
will keep you warm in winter
Nothing for you to see here, Please move along.
Use a normal UPS to bridge the first few minutes in which you can comfortable start a generator.
21x twelve voltage batteries rated at 30Ah hooked up in series :)
-Foxxz
Its like, when you're thirsty, asking for a bottle of water or asking for iodine tablets. It would be better to have both.
It really depends on how long you expect your outage to last. UPS won't last for long, yet is crucial for small burps in the supply.
For example, what if your generator runs out of gas?
Oh, and drink whiskey. Lots and lots of whiskey. It makes good antifreeze for the blood :)
A fine is a tax you pay for doing wrong and a tax is a fine you pay for doing all right.
I have a small, 20 minute UPS. Once the battery could no longer hold a charge, I took it out and replaced it with a higher capacity VRLA battery that I got from work. With one LCD and one computer, I get about 9 hours of reserve time. The UPS does not get hot, even when the battery has been significantly discharged. I plan on doing this to two other UPS that I bought at a flea market for $10.
Vote for global prefs bug
so sticking batteries in series to 250v is not going to be a good move.
stick em in parrallel and hook up a 240V inverter.
32ah is a bit on the weedy side, around 110ah is standard and easy to find. over in the uk they tend to be called leisure batteries. dont use normal car batteries they are not designed to be run down - you will damage them
Well, 4A @ 250v = 1000 W, for 8 hrs is 8 kWh. That's a lot, and would probably be very expensive to maintain with a battery-based solution. I'd say a generator would be the way to go.
If you are going to need a generator occasionally, but don't want to pay the upfront cost, you might consider hooking your DC system (assuming that it runs at 12V) into your car and then using the car as a generator
http://michaelsmith.id.au
I run a benchmarking app and leave it on, and my room is toasty all winter long. Infact, if the window is closed, it gets too warm.
Candy-Coated Knowledge
If you have gas then you can get a natural gas electrical generator. Connected to the gas line, when power goes out some models will automatically ignite and provide power to the house, some require a manual ignition.
Another approach you could take is to take steps to make your household more energy efficient -- upgrade your insulation, get energy star rated appliances, change to flourescents -- all of those things we should have learned in school and keep learning about in the adverts that come with our energy bills.
You could look into alternative energy sources, but since cost is a factor, I won't go into details, except to say the up-front costs can be prohibitive.
In all honesty, a generator IS your best option if you want to keep running in a blackout. You may be able to poke around and find a used one for 1/3 the cost of the new article.
If that's still not an option, build a fire pit and stock up on wood...
We get natural gas directly from the wellhead.
The lease dates back to the 1940s and at the time it wasn't uncommon for the leaseholder to be able to use all the gas they needed from the well for household use.
The oil and gas company that has the lease desperately wants to change those terms.
The only downsides are:
1) Occasionally the well will freeze up in the winter. That's not that much of a problem because my oldest brother who also lives on the farm is retired from that same oil and gas company and can thaw out the well.
2) There are no odorants added to the natural gas and so it has no smell to tell you that you have a gas leak. I ended up in the hospital once because of that when a natural gas heater went out and let the room fill with natural gas.
You can get used to the cold, just like anything else. Hypothermia is an absurd myth perpetuated by the heating and clothing companies to sell you their expensive and unnecessary products.
Simple as that. The first option is cheap and effective, but makes a bit of noise, and will need somewhere outside to run it. The second option needs quite a bit of space, is expensive and requires a fair amount of other expenditure for charging circuits, inverters, etc. It also runs out after a while and there is nothing you can do then. If you use a generator, you can always put more petrol/diesel in, assuming you keep a decent stock.
Solution: Google for a 1500W generator (e.g.). Problem solved - next question please.
The majority of houses in the UK do not have cellars. The majority of those that did pre-1939 have since been bombed flat.
;)
As for the second component of your comment, isn't that stating the obvious?
Personally I'd go for photovoltaic supply as I've nearly succeeded in getting a Mini-ITX based server operating 24/7 on solar power via a bank of 6v FLT batteries.
For heating, being as we face no natural-gas outages just now, I'd recommend by-productive heating from your cooking sources after their normal use. The laws of thermodynamics can be useful when heating a house by this method
Ripping an new rectum in the fabric of spacetime.
You might want to talk to an electrician who specializes in backup power systems. There are safety and electrical code issues on how circuits are switched from mains power to UPS/generator power and back again.
Mea navis aericumbens anguillis abundat
It's quite likely that you don't need heat if your power interruption is only going to be 8 hours. During the Quebec ice storm we were out of electricity for 7 days. The house will stay decently warm for the first 2 days. It will be chilly for the next 2 and getting cold after that. But even after 7 days the appartement was still above freezing in weather that was always a little below freezing.
My recommendation: don't sweat 8 hours of power failiures.
That said, if you really need electricity, say to prevent perishable from going bad your best bet is a generator essentially because it's easy to refuel and keep going for days. You also get decent power in relatively small packages.
Who modded this informative? 250 volts DC is not the same thing as UK line power. (250 Volts-rms @ 50Hz.) This idea is as dangerous as it is useless.
What you need is an inverter. The cheap ones that you can get anywhere would work fine for your computers, but for your furnace you'd need an inverter of the caliber used in off-grid homes. (Probably more than you want to spend.)
Only in a Slashdot fantasy can a Slackware install turn into several hours of sex . . . . .
Your best method (but not the cheapest) is a hybrid battery (UPS) and Generator solutions. Generators for 4Amp@250Volts are not that large, or that expensive. (Well, this is all relative I suspect, but if you think a UPS is really cheap, I figure you can afford it.)
Get a large-ish UPS that can support this power consumption for, oh, 15 minutes. Make sure your generator is ready to work at any time. Power goes out, plug the UPS into the generator, and start it up. As long as you have the UPS (a kind of power cache) your generator can act up a bit, or run out of gas, and as long as you can get all that fixed in 15 minutes, you're power supply will be constant. If you're not sure if 15 minutes is enough, get a bigger UPS.
This is more of a large scale disaster scenario setup though. I don't suspect your power company would leave the power out, in the winter time, for more than 15 minutes. If they do.... you're not the only one in deep shit!
Now, WHATEVER YOU DO, do NOT run the UPS or the Generator back into the grid!!!!! If you're thinking of setting up something a bit nicer, like running your entire house off the UPS without any cares, you'll probably need to integrate the UPS (and generator) into your home's power system. If you're doing this, do it right, don't screw around with it if you don't know what you're doing. (If your laws are anything like ours, you'll need a permit to do this in the first place, and an inspection afterwards.)
Anyhow, this is the cheapest method I could come up with that would actually work pretty well, and I have it. Truth is, I don't really need the generator, but bought one for outdoor events and camping, and figured I might as well put it to (possible) use if it's around the house most of the time.
We need a Heat Transfer Protocol for the Internet to allow transfering it around. Probably HTP/IP because you wouldn't want to accept HTP datagrams from just anyone. In any event, in case of DDoS attack, a high capacity firewall would be a good idea.
One line blog. I hear that they're called Twitters now.
The temperatures in the UK are not extreme. If your house gets cold that quickly, I would suggest to upgrade your isolation material. Or you could always use some blankets to keep you (and ..your computers) warm.
My .02 euro
And people, as anyone knows who has seen "The Matrix", are a great source of power. Have a few kids, wire 'em up to your PC, and you're online forever.
What power interruptions? I think you are talking rubbish. If you aren't, then the press are. We are in a first world country with a decent infrastructure and it is extremely unlikely that we will have mass powercuts. Unless you live in the middle of nowhere and are supplied by one overhead power line, make sure your computer is on a UPS and stop worrying about it.
A latent existence
Honestly you're right - but I've found CRT monitors more effective at producing heat. Older, larger CRT monitors are basically small space heaters. A multi-monitor setup with old IBM 'powerdisplay' model CRTs will heat a dorm room VERY quickly.
See also this detailed article on what kinds of batteries might do the job. good practicle info.
"It is a greater offense to steal men's labor, than their clothes"
Having lived through 3 hurricains in 6 weeks, after Charlie my wife made me buy a generator, best purchase I made in years ( besides that new G5 17" imac). The only generator available was a huge 12000 watt unit for like $2000. I bought it anyway, more is better right. Well we were outa power for like 10 days total, but I had the genny running and was able to power the whole house, including the A/C. Man i loved watching Lord of the Rings in the a/c, on my entertainment center, while my neighbors were trying to find out when the next shipment of ice was coming into the area. Just Kidding, I had my neighbors over to the house alot. Then we went through the other 2, needless to say that genny is hard wired into the house pannel now.
I agree with the generator AND UPS solution.
I had a generator (can't remember which one now) that featured "clean" power output for electronic devices 5-6% distortion or something like that.
I had the place wired so I could use one plug to connect the genset to the house, and then switch certain circuits over from utility to generator power.
For heat, I used a Kerosene heater (place had electric heat). I'd not recommend this option if you don't have electric heating.
The PC was powered through a surge protector, a power conditioner, and then a Automatic Voltage Regulating (AVR) UPS. Overkill, perhaps, but I never had any errors, glitches, lock-ups, or data corruption (that I could tell).
Alas, I had to move and couldn't use the genset in my new apartment. On the plus side - I haven't had a loss of power that lasted more than 10 minutes in the new place.
Solar voltaics can provide backup, as can a micro-chp station. This old article talks about micro-chp, but basically when you are heating your house you get 1kW/h of free electricity. Connect this to a fuel cell, and when you are producing excess electricity then you store it up in hydrogen. When you burst it can be taken directly from the fuel cell without paying the national grid. Use white LEDs for lighting, a VIA mini-itx for your server, and your electricity bills will be only for your cooking and heating.
Phillip.
Property for sale in Nice, France
If space isn't a huge issue, you could consider using water tanks for their thermal mass. If you keep the house heated most of the time, the water temperature will stay constant even if it's not directly heated. If the power goes out, the water's thermal mass will slow down the cooling process considerably. Ditto the heating, if your power goes out in the summer.
Always a godfather; never a god. -Gore Vidal
Um, modern inverters have real-world efficiencies of %90+. By any standard that's marvelous.
Only in a Slashdot fantasy can a Slackware install turn into several hours of sex . . . . .
Each year during winter I migrate from a PPC chip system to an Intel based system for greater warmth. In summer, I return to the cooler PPC. Just like whales.
Seriously, you probably should investigate a natural gas generator, talk to a good electrician, and be prepared to combat a plethora of zoning (or similar in the UK) restrictions. Alternativly you could reinforce the floors of your house and consider lead-acid batteries but many of these solutions are solar oriented and not ideal for the UK in winter.
It's not easy being green.
You, on the other hand, apparently do not know that all the electricity that is actually used by the computer, or any electrical appliance for that matter, eventually turns into heat. This means that it is physically impossible to have an inefficient electrical heater. Which, in turn, means that you're an idiot.
I don't suffer from insanity. I enjoy every minute of it.
Maybe. His computer doesn't run on AC at all. You can buy 12 volt power supplies for some computers. Telecom runs their computers on 48 volts DC. (not all, but all the important ones)
Light bulbs don't care about DC. Small motors don't care. I suspect that he only has two devices that care: his fridge, and his furnace. Everything else transforms either doesn't care, or transforms the AC into something else anyway, so a good hacker could find that something else and make it work.
Warning, if you consider the above, don't just try things. You never know when you will discover the rare device that does care. Do some research first. The principals apply though.
If your gas furnace's blower and exhaust fans run on electricity, which I'm pretty sure they do, you're not going to get more than a minute or two out of a UPS. Those big fans push a lot of air and draw a lot of power. If you're really worried about staying warm, get a propane space heater and a 20lb tank. It will be enough to keep a room or two warm for a couple days.
Agreed about AC and DC, but here is one thing to keep in mind.
If you run an incandesent bulb off DC it will work just fine, and probably last a VERY long time compared to how long it "should" last.
I thought the UK ran at 240 volts, not 250. I thought South Africa was the only country that ran 250. I though most of Europe was 220 and Europe and the UK were going to unify their standards at 230. Anyone care to comment? BTW, Japan runs at 100 (the lowest, 250 is the highest) and I think Trinidad runs 110 (the USA does NOT, see below).
Of course the USA used to be 110 volts, but is now 120 volts, but so many Americans still don't know that. It actually causes problems with old tube radios.
Just because it CAN be done, doesn't mean it should!
You live in the UK, which tends to not have enough sun to make photovoltaic worthwhile. Either you need a positively huge array (and the one in the picture on the website you link to looks like it fairly covers all available space on the roof) or you need lots of sun and Britain just doesn't have that.
Your best (but polluting) source of electricity is a honda generator. You can buy them all over and I'd imagine a DIY outlet will have a few models to choose from. One member here mentions that he did quite well after a hurricane with one. Do not ever run one indoors. They create carbon monoxide so their exhaust needs to be away from the house so that it cannot seep in through a window, vent or other entrance.
You will need a UPS with a generator if you are running a computer, but you don't need one for equipment that may be shut off and restarted, like fans, washers, dryers, refrigerators, etc. You need enough battery life to be able to survive a power outage until you can get the generator running. So if your computer needs to run all of the time, make sure your battery will last long enough for you to wake up, put on clothes and go tend to the generator.
Insulation and sealing are the best non-polluting way to increase heat -- and you will save money on heating fuel all winter, so it pays for itself.
The more insulation you have in your walls and on the roof, the better you are. Be sure there is an air pocket that runs up your eaves on your roof so that you don't get mold on your rafters and shingles and you're all set. You want to add to your "R-Value" in such a way so that you can keep enough home heat inside to keep warm in any full-day power outage.
The homes I've visited in England have tended to be fairly drafty as compared to US homes. So look at your doors and windows and make sure they seal well when you close them. Windows ought to be double-pane windows, which hold in heat four times better than single-pane.
I don't necessarily recommend that you keep up the electricity lifestyle during a power outage. Turn off your computer, unless you need it for work. Use hurricane lanterns and "Coleman" white gas lanters with mantles to light up your home (they'll also add heat but not as efficiently, perhaps, as a real heater). Run up your heater on your generator until it is quite warm inside and then shut it off until things cool down just under bearable temperatures. Don't open any windows to moderate the heat and keep things sealed up as best you can. Don't use the television, save to get information about the power emergency (a radio is usually better anyway for up-to-the-moment information anyway). Run your generator sparingly.
And talk to your local MP and ask why your area is so ill-served with electricity. Ask if his district is not one of second-class citizenry if your power goes out as often as is predicted. Gather your friends and neighbors to help him think more clearly (if he sees you as a voting bloc, he'll think clearly) about the need to introduce a change in the system.
Gods don't kill people, people with gods kill people.
You can run a gas furnace off of the heat generated from the pilot light using a thermopile and a millivolt controller gas valve. I have heated my house this way in the middle of winter over a 3 day ice storm blackout.
It must be a hot water system. Just open all of the zone valves and eventually the whole system will heat up to the furnace temperature via convection in the pipes. The furnace will cycle between its low and high temperature, even with no power except the thermopile.
This is a standard type of system in the US. Not sure about the UK.
See http://hearth.com/what/gas/howgasworks.html for info on millivolt gas systems.
(I'm not affiliated with Xantrex.)
For the best inverters I know of, use Xantrex.
Get a bank of 12V batteries, like marine, or car batteries, and run it through something like this, or pop for the integrated solution like this.
Also take a look at those neat solar arrays.
A very close associate of mine uses Xantrex's Trace inverters with a system of LP gas generators, solar arrays, and battery banks to provide power to an off-grid site on a barrier island. When the sun shines (a lot of the time) the solar keeps the batteries charged. The inverter powers the camp from the bateries, and if someone plugs in a hair-dryer (or the sun doesn't shine for a few days) the inverter can turn on the generator to boost the juice, and refresh the batteries. The tricky part is regulating the temerature on the batterie bank. If it gets too hot, it'll "boil" the batteries and they won't be for shit until you fill 'em with distilled water and say a prayer.
mod up.
backup heating doesn't have to be the furnace... unless you got some very important stuff there in which case you should have a generator anyways.
world was created 5 seconds before this post as it is.
http://www.sunmachine.de/english/index_y.html
Not in full production yet but should be in a year or so. Once it is it'll be possible to have your own solar power station in your back garden.
35% efficient at converting heat into electricity and the rest of the heat is used for central heating and hot water giving an overall efficiency of 90% or so. If not enough sun, it can switch to gas powered generation.
Will it compete with a cheap petrol generator? Not in the short term. In the long term, it supplies electricity to the grid as well as heating the house, so not only does it reduce your bills, it actually earns some cash.
Deleted
A co-worker had seen the exact same thing happen in his last job.
I'm not familiar with what "VRLA" means, but unless the battery is sealed gel-type and rated for deep discharge and repeated cycling, I'd wouldn't use it.
Get your facts right. I don't know what coverage you're reading (the tabloid papers I suspect) but there is no power supply crisis forcast for this winter.
What has been commented on is our increasing reliance on imported power from the continent, and coupled with the decommissiong of several major nuclear power plants over the next decade if we don't act now there could be problems in the future. I don't think UPS'ing your heating system is necessary just yet :)
"But the government said the outlook for power supplies this winter was good and accused the union of "scaremongering""
Source: http://news.bbc.co.uk/1/hi/business/3751810.stm
An alternator produces AC anyway, no need for an inverter. Just a 10x (or 20x, if you are on 240v) steup transformer, and make sure the RPM stays stable so that it produces as close to 60hz (or 50) as possible. And dont run any electronic equipment directly off it - eg stick with lamps and motors (eg, the forced-air furnace would be fine)
For all the posters in this thread :
DO NOT USE HIGH VOLTAGE DC IN YOUR HOUSE.
Apart from the obvious issue with appliances, there's another reason.
Mains 240V AC switches are not rated for that kind of DC voltage - the arc from switching DC at those voltages will most likely destroy the switch. This arc is only brief with AC at 50/60 Hz as the arc will extinguish when the voltage drops to zero every half-cycle.
This is why switches are normally rated along the lines of "240VAC/32VDC"
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Actually, all switching power supplies take the input line voltage and rectify them to DC anyway. It is perfectly acceptable to feed them DC straight off. The DC potential needed would be equivalent to the peak-to-peak of the minimum recommended AC operating voltage of the unit. For 120vac, 60Hz, this would be 120*sqrt(2)=170v.
That's probably less than it would cost you to add a SINGLE additional battery to your system.
Here's how: Find yourself an old "horizontal" style lawnmower engine (anything over 2HP will do) and a car alternator - the bigger the better. Put a pully on each, string a V-belt between them and bolt them down to a thick piece of plywood or better, some sort of metal frame. Using the wire from a set of old booster-cables, hook the output from the alternator (which should be outside, of course) through the nearest convenient window (or drill a hole in the wall) and across your UPS battery (making sure it is the CORRECT POLARITY). When the power goes out for more than 20 minutes, go outside and start up the engine for practically unlimited runtime.
Even with a small car alternator, this rig will easily give you 12 volts at fifty amps. If you use a larger alternator, like the kind you would find on a truck, you can get 12 volts at up to a HUNDRED amps (= 1,200 watts).
I once put a system like this together for fun for under $50.00 CDN, ($30.00 for a beat-up old engine in the local bargain-finder and $20.00 for an alternator from the local scrapyard.) This is significantly less expensive than buying even a single extra battery, which would cost about $80.00. The thing would run for HOURS before needing refueling, and if I wanted longer runtime I could have just added a bigger gas tank.
Now, before you pack up your wrenches and head down to the local scrapyard, there is something you need to check: Does your UPS use a single large 12-volt battery, or does it use two smaller 12-volt batteries in SERIES for a total of 24-volts? If your system has two 12-volt batteries in series, you're going to need a 24-volt alternator. Where do you get a 24 volt alternator? Well, most Land Rover vehicles have 24-volt alternators, as would practically any kind of emergency vehicle, most military vehicles, and many large trucks. So, if you need a 24-volt alternator and can't find a Land Rover at your local wreckers, head to an INDUSTRIAL vehicle scrapyard.
For the load you initially described, (250 volts @ 4 amps = 1,000 watts at continuous use) you would need a sustained power INPUT of about 1,200 watts. Note however, that in reality you will probably NOT need 1,000 watts continuous output as your furnace blower will be cycling on and off as will the other loads in your house. The UPS's battery will cover the extra load when everything IS running and recharge from the alternator when it ISN'T. This means you can likely get by with a smaller alternator.
Overall, the solution I have described is ugly, noisy, and isn't likely to last through more than 100 hours of use. But it's also cheap, light (compared to a battery), easy to hook into the UPS, quite reliable, and works great if you only need a few hours of additional electrical power. If you're mechanically inclined, this is the cheapest and most effective solution I can think of.
If you're really keen on the whole batteries/UPS/alternator modding-it-to-run-on-practically-any-source-of-pow er thing or just want even more reasons why trying to run it off solar power would be a terrible idea (at least where you live), I did a really interesting writeup on this for an anti-landmine technology competition a few years back. We made the whole reference design that we came up with effectively "open-source", so feel free to use it as you please. You can have a look at that here: http://www.intellicharge.ca/Downloads/Downloads.ht m The server has pretty serious bandwidth so it should be relatively /. resistant, but please don't rack up our hosting bill by downloading the full 1200dpi 114 MEG "print resolution" version unless you have good
Honestly you're right - but I've found CRT monitors more effective at producing heat. Older, larger CRT monitors are basically small space heaters. A multi-monitor setup with old IBM 'powerdisplay' model CRTs will heat a dorm room VERY quickly.
You mean like this?
Yes, they are all functional, and there is even one more screen you can't see in this picture.
coleman gas lanterns or stoves or heaters that run on liquid coleman fuel or unleaded gasoline "white gas" are not recommended for indoor use. You'll kill yourself with CO buildup as they are sucking O2 out of the air. They will even tell you that on the box. The propane fired ones are a lot cleaner and safer to burn indoors, and even then you should have some windows cracked. You can get adapters for around 10$ that will let you attach them to a 20 lb refillable tank instead of the expensive 1lb throw aways they come with.
I read that University dorms are having to be upgraded "spec wise" for electrical power because of people like you. You oughta be proud.
"Using an Inverter is a HIGHLY inefficient power source!"
Well, yeah, but since all of his computers and appliances and everything are designed to run off AC, you *need* an inverter to get AC out of your DC batteries.
Converting all his equipment to DC would be extremely complicated, not to mention prohibitively expensive.
DRM 'manages access' in the same way that a prison 'manages freedom'
VRLA is Valve Regulated Lead Acid...VRLA is better than a sealed lead acid precisely because it will NOT explode- it will vent if charged too fast.
VRLA is a teensy bit different from a standard gel cell in terms of charge profile, but they're close enough that it shouldn't matter much; I think the float voltage is typically lower. HOWEVER, you DO need to make sure you match specifications ( and not just "12v", get the specs sheet and look at the charge, float, etc voltages), and be aware that VRLAs are not particularly fond of heat; adding a tiny fan to the UPS enclosure would probably be a swell idea anyway as the buggers tend to run hot.
The REALLY thorough will check the charge current from the UPS. UPS makers are under pressure to get the battery charged back up quickly, and they may push the limits of the battery's charge current. It's generally C/20 where C = A/Hr capacity; ie a 20Ahr battery should not be charged faster than 1A continuous (a brief peak charge might be OK, and if so, will be specified in current and duration). Charging too fast will cause gassing, overheating- and past a certain point, like many other batteries, lead acid batteries of any type can go into thermal runaway, which is not pretty.
Adding in extra batteries into a UPS not designed for expansion will be trouble, on the charging side of the equation. If you've ever had a completely dead car battery and tried to charge it with a charger, you know what I'm talking about- the voltage drop is so great, the battery practically acts like a short and will cause the charger to overload. The same thing could happen with a UPS. A good sign is if there are battery expansion packs available for your UPS; use that as a guide for sizing.
Oh, and by the way, you may want to consider adjusting your UPS to use the proper float voltage (not for the faint of heart, but possible on some UPS's without soldering), and again, installing a low-speed fan to move some air through the thing and keep everything cool. Many UPS vendors coughAPCcough set their float voltages too high and thus cook the batteries, and the elevated temperatures don't help either; that all makes for a nice revenue stream, as they charge a fortune for replacement packs(which are almost always made up of standard-size batteries, and thus available much more cheaply if you're the enterprising type). Properly maintained lead-acid batteries should last almost a decade- yet most UPS batteries die within a matter of 2-3 years. It's pathetic, considering how much lead is in them and how most people probably don't dispose of the UPS's or the batteries properly.
Please help metamoderate.
"Dont put car batteries inside your home."
At least explain why. Wet cell batteries vent (explosive) hydrogen when charging. That's why when you jumpstart a car you make the final connection to ground (earth) away from the battery. Too much hydrogen floating around the battery that a stray spark could ignite.
Sealed gel batteries, which to not vent, are fine indoors. That's what most UPSes use.
DRM 'manages access' in the same way that a prison 'manages freedom'
I'm surprised at how many people suggested the use of batteries and an inverter. The ammount of batteries that you need to provide 8hours of 250v at 4amp would occupy an entire garage. It would be a magnitude cheaper to just buy a gas/diesel generator.
For God's sake, be careful if you use propane or any other type of heater that is not intended for indoor use. Burning propane generates carbon monoxide, which is deadly and odorless, so make sure that the heater you use is properly vented. New York City just passed a law requiring all residences to have carbon monoxide detectors, following the deaths of three women from co poisoning due to a faulty flue. A search of a newspaper database for propane heater carbon monoxie poisoning turned up 327 articles. Remember that in 1994, tennis star Vitas Gerulaitis died from a faulty heater.
get a propane space heater and a 20lb tank
Don't do this. Catalytic propane space heaters are meant to be used in open, well-ventilated areas, like outdoors. Used in enclosed spaces, a dangerous level of CO2 can build, which can be potentially lethal. This is especially dangerous in an outage situation, where you're likely to huddle in a smaller, well insulated room and close the doors.
Your best bet for an emergency heat source is a fireplace. Wood is good, but propane is simpler to operate, easier to install, and lower maintenace. It's safer than a space heater because it vents exhaust gases outside and the tank (usually larger than 20lb) is stored outside your home. Some models have a fan to use convective heating, making them more efficient. This fan is usually small and lower power, suitable for a reasonably sized UPS.
It may cost a little more, but you also gain the aesthetic benefits of having a fireplace to use anytime, whereas the space heater is often an ugly looking contraption.
No, you're wrong. A perfectly efficient electrical heater would turn all electricity into heat. Ironically, *all* machines are perfectly efficient heaters over a long enough time scale - go thermodynamics! You're mistaking efficiency (percent of input converted to output) for efficacy, as another poster put it. A perfectly *effective* heater would do it instantly.
Further, once your computer reaches steady-state, it is in fact distributing the entirety of its heat to the room around it. It doesn't matter that the heat might take an hour to work its way out from the processor - after an hour, the computer will constantly be radiating its full heat content. For a 'real world' example of similar behavior, look at the sun. The energy being radiated from the sun right now was actually generated several million years ago in the fusion core, and has been working its way out ever since. However, (assuming that the sun's output is unchanging on the time scale we're looking at) the energy output of the sun is equivalent to the energy generated; otherwise, the sun would continue heating.
Basically, heat has to go somewhere. Once your computers' temperature has stabilized, the radiated heat must equal the generated heat; it doesn't matter that the heat being radiated takes time to radiate, only that it does.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
Actually, typical residential service in the US is 240V split-phase; the distribution transformer is center-tapped, and the center tap is grounded to serve as the neutral. Phase-to-neutral is 120, phase-to-phase is 240. Heavy-draw appliances, such as large air conditioners, electric ovens, dryers, etc. are usually run on 240.
Another system uses two of three phases on a 208V three-phase supply; phase-to-neutral is still 120. This is normally only found in apartments and commercial buildings.
Oh, no! You have walked into the slavering fangs of a lurking grue!
replace all your computers with Athlon XP boxes. if your heater cuts out, the computers will keep the house warm.
Finally something on slashdot that I know something about. We went through a major ice storm here(Oklahoma) about 3 years ago. If heat is what you are concerned with get a gas catalytic heater in the 20k to 30k btu range. We had one on hand still in the box and hooked it up and lit it about the time the juice went off. We expected to keep a couple of rooms warm but were pleasantly surprised to find that it kept the whole house toasty for the 2 weeks we were with out utility electricity. Make sure you figure a way to hook it up to your gas service beforehand. We used an airhose tee'd into the line going to the furnace. It won't pass anyone's code but if you get in this kind of shape the authorities will have their hands full with other things. The heater is pretty clean burning but there is no flue so you need to go outside once in awhile just to make sure you change some air. We did eventually borrow a generator from family living outside the blackout zone. Neighbors bought generators by the hundreds. Most got 5KW models. They were able to run part of the house at a time - freezer and refrigerator and some lights or furnace and some lights when that was a priority. 10KW should let you live quite comfortably. The generator we borrowed ran off the PTO of a tractor and was 13 KW. We didn't run the furnace but kept using the catalytic heater. That way we could shut off the generator part of the time and still keep warm. The generator was an older model that had brushes and the lights flickered some but some of the more modern brushless ones flickered too. The only appliance that seemed to take exception to it was the microwave oven. When we tried to use it it sounded like it would come off the shelf so it stayed parked for the duration. Real electronics mostly run on rectified DC internally so the flicker gets filtered out. Had no trouble whatsoever with any of those things. People warned that months down the road troubles could arise but we have seen nothing that seems related to the outage. The heater we had was around $150US and the 5KW generators were $500 to $600. I don't think I would consider trying to do what you suggest with batteries. Both heater and generator will cost almost nothing in maintenance if you never use them but batteries will go bad no matter what. You know your situation best. There was at least on fatality from CO from a generator during the time we were blacked out, so that is something to be aware of. Some of the generators developed carburator icing problems when run for hours on end. They really weren't made for quite that kind of service but there were few if any outright failures. redsilo
But it's extremly rare to find anything made for any voltage between 220v & 250 that doesn't work or cause problems.
Really other than things made for the US & other weird places, everthing made to run on mains for the last 50 years is to designed to run on any voltage between 220v & 250v wihtout a hiccup.
You're talking about 4 amps at 250 V, over a period of 8 hours. That's 1000 watts for eight hours, or 8 kilowatt hours. However, this doesn't cater for the power factor -- if your house has a power factor of 0.8, for example, batteries capable of providing that current for that period of time will run your house for about six and a half hours. So you'll need to bring up the batteries to 10 kilowatt hours to compensate -- either that, or (if it's an inductive load) buy a whopping great big bank of capacitors to bring the power factor back up to a reasonable level.
Umm you got it backwards.. Lets go to the facts..
Starting with some glossary terms..
Volts = Electrical pressure
Amps = Electrical current
Watts = Power
VoltAmps = Volts * Amps
Vars = Volts Amps Reactive.
Power Factor = Percent of Volt Amps that are Power scaled 0-1.
What's it mean?
If you drop a Capacitor on an AC line, it will draw current but not get hot unless it's not designed for the voltage, current, or polarity.
The current is said to be reactive. All of the current measured in VA is not Watts. The power Factor is zero. Volts * amps * power factor = watts. Most inverters don't like a highly reactive load. This may dammage it.
A light bulb gets hot. It is not an inductor or capacitor.. It has a power factor of 1. Volts * amps * power factor = Watts.
A furnace motor may have a power factor of 0.8. If it drew 4 amps at 250 volts it's VA = 4*250 or 1000VA. The actual power draw in watts is 80% of tthe VA. Remember power = Volts * Amps * Power Factor or 250 * 4 * 0.8 = 800 Watts.
So in the above example in the parant, the load draws 800 watts. If it draws it for 8 hours, that's 6.4 KWH not 10 KWH.
Remember that inverters don't like reactive loads. The inverter may take the reactive power and dump it as heat depending on the design. That's 200 watts of reactive power. You also need to scale for conversion consumption. The inverter uses power. It is not a lossless process.
If you run large reactive loads, save your inverter by looking into doing some power factor correction.
With a reactive load such as a transformer or motor, the current lags the voltage. In a capacitive load such as a noise filter, current leads the voltage. It is possible to correct reactive load problems with lamp ballasts, motors and transformers by adding capacitors to the line. You want a capacitor that has the same VAR rating as the load you are trying to correct. In the above example, we have a reactive component of 200 watts. (800 true watts subtracted from the 1000 VA leaves the reactive component of 200 watts reactive) Adding 200 watts capacitive reactance will cancel out the inductive reactance load. This will reduce the load on the inverter. Now it sees a 800 VA load, not a 1000 VA load. Now the inverter sees a power factor corrected to 1. The motor still draws 1000 VA but now gets the 200 VA reactive component from the capacitor, not the inverter.
I hope I didn't loose too many in the dry discussion of what a VAR is.
Anyway, this is the reason on some power poles, you may see a bank of capacitors. It is used to correct power factor and reduce the amprage load on a substation.
The truth shall set you free!
I do grant you that solar panels are expensive. But it could be a worthwhile expense.
My approach is that everything that I want to keep running when the power goes out should run from either 12V or 24V. I have a 24VDC system. Two 12V batteries in series for 24V, and a third 12V battery which is kept charged by a DC/DC converter. (This was mostly because I had surplus batteries; 12V alone would be fine for many purposes. My earlier attempt was with a pair of 6V golf-cart batteries in series. These are capable of storing a lot of energy, and they last a long time if well taken care of, but they do consume water.) The 24V system is charged by a pair of large solar panels on the roof, which I got used on ebay. I'm a little underwhelmed though with the current that I'm getting out of them, so suggest you should get new ones with the best efficiency you can find. Today I was getting a peak of 3 amps charge current. That's only 72 watts, and it is not providing that much all day long, either. Consequently my "secondary" grid-powered battery charger is providing most of the charging. I have 2 computers running on batteries now, and together they draw about 4 amps continuously from the 24V supply. One is an Athlon with an Orion 24V ATX power supply, and the other is a fanless Epia 600, supposedly low power, but it is drawing a bit over 2 amps off the 12V supply (which translates to a bit over 1 amp off the 24V supply). The Epia has one of these, which gives me the flexibility to run from either voltage.
CRTs are line-powered but LCDs typically run from a lower voltage. Right now I have two big CRTs for my main system and they are power hogs, and generate a lot of heat. Some day I will upgrade, and I think it's possible to find LCDs which have wall-wart power supplies rather than built-in. I would bet some of them are 12V too. So then I will be set - I could do any kind of computing I like even during a power outage. A laptop is also a good solution, but those usually charge from less standard voltages, like 16 or 18. It's unfortunate.
12V lighting is easy, because RVers use so much of it. You can find 12V fluorescent lights, halogen track lights (but that's kindof wasteful), LED lights etc. In an extended power outage I would turn off one or both of the computers, and then the 24V battery would keep the 12V battery charged, and I could have lighting indefinitely as the solar panels charge the 24V battery every day. The kitchen has a drop ceiling with several 4' grid-powered fluorescent lights already. I added a 2' 12V powered RV light. It is well hidden above the translucent ceiling panels, and provides enough light to get by.
For my computer rack I made a panel with efficient switching DC/DC converters that supply 5V and 3.3V as well, for things that would otherwise have been powered by inefficient "wall wart" power supplies. Just consolidating all of those to a single source should save a lot of power. The panel has a bunch of these connectors. I use red & black for 12V, blue & black for 24V, orange & black for 5V and yellow & black for 3.3V. (I debated about whether to follow the PC power supply color convention, but the ham radio guys have already chosen red for 12V, and that doesn't match.) I plan to use brown for any other odd voltage that I may need later; I notice a lot of things running from 7.5V, for instance (hubs and scanners and stuff like that). I used some panel-mount holders like these to mount them on a rack panel. If you don't want to make your own p
Some APC UPS units have an external connector normally used for disconnecting the built-in battery for safe shipping or in case of fire. By replacing the internal battery with a wire-loop, the external connector can be used to conveniently hook up large batteries. (Watch the polarity!)
The SmartUPS 1400 model pictured is a 24 volt system, so 2 serially connected deep-cycle lead acid batteries must be used.
ups1
ups2
This setup worked great during the recent hurricanes and power outages in Florida. It kept my laptop, cell phones and flashlights charged during the outages, the longest of which was about 5 days. During prolonged outages you would want to turn the UPS off, and only run it for an hour a day or so to charge smaller devices, check the news, etc.
Your car is a self-contained habitation module. Given a supply of dead dinosaurs, it'll produce plenty of heat and electricity. Here's how to get them out of the car and into your house. I haven't actually set this up yet but I've been considering it for a long time. Give a think to this plan:
The electricity is pretty simple. Your stock alternator produces 14 volts DC at somewhere between 50 and 100 amps. After derating for alternator heating, and inverter losses, figure about 500 watts of useful continuous power, with momentary surge capacity of at least 2kW. Inverters that produce more than 100 watts or so should be wired straight in.
For the heat, you'll need a way to circulate the engine's coolant into the house and back. Pick up a "radiator flush" kit at the auto store. It's a set of tee fittings that install inline with the radiator hoses, and have threads for garden hoses to screw on. Pick up a radiator from the junkyard, and a bunch of hose that can handle the temperature and pressure involved. Plumb your new radiator in parallel with the existing one.
After filling the whole mess with coolant, doublecheck all your hoseclamps and start 'er up. As the engine heats up, the thermostat will open and both radiators should get warm. If you need to divert more flow to the external one, try pinching or adding a valve to one of the hoses. Put a small fan on your in-house radiator and voila!
Now the only problem is that Murphy's law guarantees a power failure will happen when your tank is almost empty. Diesel keeps well, but gasoline turns to varnish after a few months in storage, so if you're going to keep a few gallons in a spare can, change it out regularly.
(Please note: Make damn sure all your hoses and fittings can handle the temperatures and pressures involved. Check the coolant level after the bubbles work out. Keep an eye on engine temp if you choose to restrict the hose, and pay special attention if the engine's radiator fan comes on, which probably indicates inadequate coolant flow. Provide adequate airflow over the inverter's heatsink. Don't touch wiring with your hands covered in coolant. I'm not responsible if you blow yourself up.)
The cheapest solution is to go around, find and buy used diesel power generator.
Put it into a garage or cellar, connect exhaust pipes to outside, and finally get an electrician to connect it to house grid.
Ok - they are big and noisy when started, but I've seen such solution and it works better than anything on led batteries, which tend to go down in really cold weather.
I've a little confusion about exactly what you'd need a heater for when you say the cost of running a generator during the summer cooling season is $300 for a week, but other than that, I'll try and adress some things...
You mention all those things for 'survival' and 'mininum comfort'. And then you list things like a 19" TV and a computer.
First off, that's not survival. That's luxury. Surely you've seen books before. They're quite entertaining, and generally a bit more enlightening than watching CBS (or whatever people watch these days). They also don't have the irritating feature that causes them to stop working when there's no electricity.
First off, an electric-ignition furnace doesn't need constant electricity to keep it running, just for ignition. Get your house warm, and turn the generator off for a couple hours. If it gets cool during those several hours, fire it up again and start the furnace, and turn off the generator. If it is indeed warm there, I don't see what you'd need a heater for at all, and air conditioning is a luxury as well. Drink some water - it's good for you, cleans your body, keeps you cool, and doesn't consume electricity to produce. But then, if you're one of those people that have a fit when they start to sweat, I can understand your need there - for "survival".
Second, if it's cold out, you don't need to power a fridge. Take the food, put it in boxes, and put it -outdoors-. Diary products and meats will be fine, for the most part. You could also try putting it in coolers, along with some ice you've grabbed from outdoors. Conceiveably, it wouldn't be too entirely difficult to do without a fridge at all - like your grandparents did when they were younger (and possibly your parents, if you're 35+).
It's also not necessary to power a water pump in most scenarios to keep water pressure up. (provided that's the kind of well you're talking about - if you're refering to a sump well pump, that's another matter entirely...) The pressure in a line will remain sufficient to flush the toilet several times, wash your hands, and perform basic tasks a time or two in most houses. If pressure goes dead, just turn the pump on to do your thing, and then turn it off once youre done and the pressure is high again. Realistically, you could easily get by on little and infrequent power to the water pump. (My wife and I did just fine for 3 days when we moved into our last place without running water. We'd just asked the neighbors if we could use their outdoor tap, and got a ten or so buckets a day for things like dishes, flushing the toilet, and bathing.)
I'm sure you'd probably be surprised, but people 100 years ago did just fine during the hot, sweltering evenings without electricity. Before all these modern trapings, people were able to entertain themselves through the employment of their mind and bodies. They might sing, read, write, dance, talk and socialize, play cards, or any number of other things. You look at things such as TV as a luxury, but really, it provides little satisfaction compared to a high-energy social gathering - particularly one where you have to go through a little 'hardship' in order to have a good time. Maybe your neighbors' beer is warm - that just makes the 12 pack that someone manages to find in a store's freezer after the 3rd day all the more enjoyable. Years down the line, will you look back on the event and think, "man, I'm glad I had that generator", because it made you comfortable? Will you look back more fondly on the event than those that got together with their neighbors, sat around, and had a break from the monotony of modern life? "Hey, Bill. Remember 4 years ago during Frances when John got that cold 12 pack of shitty Miller Lite, and how good it tasted all the same? That was a great time."
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
Most gas furnaces require power to drive the fan, and a little power to turn on the valve for the gas (controlled by the thermostat).
During the prolonged power outage during the ice storm of 1998 in eastern Canada, we fixed up a workable solution. Roughly 24V DC from sealed lead-acid batteries was enough to switch the valve, and the hooked the fan up to a bicycle. A few minutes of peddling on the bike would heat the house several degrees, and the peddler similarly. A bit more detail is contained in one of the articles in Stories from the Ice Storm.
That being said, this may not be possible with modern furnaces. Also, your house, unless very poorly insulated, will stay warm enough to live for 8 hours. (Then again, my "very poorly insulated" might be your "adequately insulated".)