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If you have a PTO (power take-off) on the transmission, look into these:

http://www.cumminsonan.com/cm/products/pto

Downside is you are using transport fuel for running equipment. Upside is you get more use out of what you already have, weighs almost nothing (compared to batteries) and takes up no space in the living area. Great option if you can swap out for a diesel powertrain.

If you don't have a PTO, look for a good quality inverter and battery system:

http://www.xantrex.com/

Another poster mentioned using golf car batteries. Cheap, easily available and (if maintained) will last a very long time. Downside is they are large and heavy, and outgas H2 when charging (so don't put them in the actual van). Maybe build them into something like this: http://www.stowaway2.com/hitch-cargo-carriers.aspx

..what's called a charge controller for your solar panels BEFORE it feeds into the batteries, and then you might as well just then complete the rig with a charger/inverter device (here, check out xantrex company, they have some info and a product range). That's the proper way to do a solar rig with battery backup. You get the solar input when it is there, you get grid input when you might need it, both sources go to the batteries, the batteries feed back to the charger/inverter and that goes to your circuit box. Then it is seamless and automatic, mostly just do battery maintenance once a month or something, top off with distiled water. Direct connection solar panel to device is only for the most low powered gadgets with a a very small solar panel. And the reason is solar panels are unregulated voltage, the brighter/sunnier, the more you get, sometimes over 20 volts on a panel (conversely I have seen half a volt from a full moon!). There isn't much lost in a modern system, don't worry about it. If you really just want pure DC, with zero grid ties at all, that is doable, look for "off grid" or marine or RV packages/systems and how they are designed. You eliminate the inverter part, but keep the rest. They come in multiples of 12, 12 vdc, 24 and 48 are the most common. You *will* need the appropriate charge controller though, to sit between the panels and the batteries, or you will cook your batteries. And you can get 12 vdc power supplies designed for mini itx cheap enough if that sort of machine would work for you instead of the atx desktop.

Xantrex has everything you need for the indoor part of your project, whether grid-tied (called "net metering" in Canada) or battery-based.

How does this converter box work with the battery-powered TV I used during the last blackout to get the latest news and information?

Do you have a car? Does it have a battery? If so, any inexpensive inverter should be able to power the box.

http://www.xantrex.com/ Pick one. I have the 1KW unit. It runs my computer, lights, fridge and TV. Keep a full spare can of gas handy.

No debut that you have to account for your local climate in figuring out how much power you get from your panels, but that bit about batteries and supper expensive inverters? That was true maybe a decade ago. It's nothing like that now.
http://www.xantrex.com/web/id/172/p/1/pt/23/product.asp

One box, sell the power to the utility when you aren't using it, buy it back when you need it.

• I took two cameras, my good camera, and a cheap(also small and light), $100 auto-focus point and shoot that I didn't really mind if it fell in the drink while I was fording a river trying to get a picture of friends swiming in the bowl of a waterfall (I skinned my leg, but the camera came out OK...).
• mono-pod. It's almost as good as a tripod for most pictures, and it can double as a walking stick and a baton (if worst comes to worst).
  If you really need tripod steadiness, then lean it against a rock or something.
• I second the motion for lots of memory sticks.... You never want to run out of storage for that one really good picture.
• ditto for spare batteries..
• a small inverter -- that can convert 12V to mains power... Good for charging while in a vehicle., etc.Also good if you're out in the middle of nowhere with nothing but a vehicle for a power source.

As many have noted, you'll need batteries for storage -- but, if you're willing to improvise and salvage, there there might be a reasonable supply of dead cars with batteries that you can use at most North American disasters. (with the appropriate infrastructure preparation).

In any case, wind and solar are a bit unpredictable. The last thing you'd want would be a couple of calm, overcast days when you really need that power. At the very least, you're going to need some sort of backup generator for 'emergency emergency' power -- although that might just be a vehicle engine alternator and long jumper cables, depending on just how much power you need for minimal critical operation (most cars can easily generate a couple hundred watts). The long-term generator capability of a vehicle alernator is a good thing to know in an emergency.

If you can put a 'hybred car' in your budget and are willing to risk the warranty on it's electrical system (or can get a development deal with the manufacturer), you might end up with an emergency transport system that doubles as an emergency backup power generator.

Xantrax, among other companies make power inverters that can take 12V (car) or 24V(truck) and turn it into mains (110VAC) level power at anywhere from 100W (plugs into a car's accesory plug and can power a laptop/cell phone, etc). to the Kilowatt range (would need a heavy-duty semi-permanent connection, but you could handle a bunch of desktop power-hog computers).

I guess that I don't have to say that, in terms of minimal power consumption, laptops are probably your best bet. If you're mostly looking at communications capability and light computing (( e.g. keeping a local database of known survivors & victims)), you can use low end (and even used) laptops. Ruggedized might be nice, but I'm guessing that you can find at least one or two intact rooms to put your communication system into (or just a semi-trailer), so a good, rugged storage case for transport of the machines would probably be far more efficient (and you could fit a dozen or so laptops into one mid-sized case).

If you're willing to use Linux instead of Windows/Mac, you can have some (most) of your machines netboot -- which cuts cost and power going to the user hard drives. Knoppix TerminalServer is really good for this sort of application because the OS disk is pre-compressed which saves on bandwidth and caching. If you want to provide local swap, buy a case of 356-512MB USB sticks from a clearance centre.
.. samnospam(sic) at bcgreen com for more thoughts.

Solar and wind generators will mean that you can always have at least some functionality even if there is no fuel at all available.. being able to use generators (even if just jury rigged from a vehicle) means that you'll have power generation available even on a calm night. Between the two you should be able to handle all but the most perverse post-disaster situations.

Nice. I've used the SW4048, so we're on the same page with that. Fried linesman is one thing, but I'm talking about measly 250W PSU's that fail, with literally flames shooting out the back. Think about where you have thousands of amps at 48V or higher available, the potential for destruction is much larger.

Creating a small line interactive only power converter would be an interesting problem. Personally if it was my system, I'd like to be able to power the house during blackouts, as well as condition the power during brownouts.

Have you by any chance used the SWCA communication interface for the SW inverter? It seems to contain a PIC in the DB25 shell, probably to convert whatever the inverter talks on that port to RS232.

Yeah the output waveform of the trace is interesting when the load changes, also as it syncs to a gasoline generator you can see it slowly change the phase.

It's nice to see someone else who actually knows about this stuff here on slashdot.

If you don't have a generator (and even if you do), power inverters can be real useful... These things can take 12Volt powr and provide 110 for things ranging from laptops to power tools. This means that they can run off of your car's battery and generator. Xantrex (formerly statpower) is who I know, but there are now many other similar suppliers of these things... They start at about $40, and can be found at places like Radio Shack. They're invaluable when you're mobile/remote/stranded or just plain out of mains power (to steal the british saying).

They range from a tiny 75watt unit that can plug into your accessory outlet, and should handle most chargers and laptops to units over a kilowatt that will probably need to be wired direct to your electrical system (presuming that it's even robust enough to drive the monster at full load).

Once you've got that, I'd also suggest a couple of jell cells, for running things that want mains power when you're in places like a hotel room with no power (you can charge them off of the vehicle power during the day). I wire mine with a 12-volt accessory plug (make sure to put a fuse on it). You can often get them out of small dead UPSs.

You can use them when you're mobile, and after you've placed your larger generators where they're most needed. I first came up with the idea in my tree-hugging days when I needed to charge a video camera battery at a logging protest and the only power I had access to was an RCMP vehicle.

If you haven't already thought of it: communications equipment, including hand-radios. I wouldn't presume that cell phone service id reinstated wherever you're going.

like sunny boy inverters, google for them

The sunny boy inverters would actually be a very poor choice, because they shut down when the grid power goes. They are designed only to add your solar input to an existing AC system.

I would, instead, suggest getting an inverter from Xantrex/Trace or from Outback Power Systems. These are also grid-tie inverters, but can support being attached to a battery system.

A different, and perhaps better (and definitely much cheaper) solution, would be to purchase 12VDC power supplies from Mini-Box and cobining this with a 12V battery system and charger.

FYI, here's a small primer on how large scale generation works: first there is a generation source, producing low (5-20 kV) voltage electricity, which is then 'stepped up' by a transformer to above 100 kV over alternating current. This is then sent through power wires to a substation which then 'steps down' the current to residential levels (there may be multiple transformers up and down).

The big difference is PV is distributed . This means a far more efficient, redundant, and secure grid. But it also mean less grid stress, because more power is generated locally. For example, normally my power comes from my roof (distance 20 ft). Sometimes some of my power comes from my neighbor (dis. 500 ft). Occasionally some my power comes from the shopping mall (distance 3 miles). When the insolation is low some of my power is imported from 2 states away (600 miles). Say the weighted average distance my power travels is 1 mile (down the same wires it would have before). Now compare that to the centralized infrastructure we currently use which 90% of the time its traveling 600 miles! Transmission efficiency is improved and grid utilization is reduced.

For the 'grid' is a misnomer - its NOT a two-way street

And that the EROEI is quite different when you consider solar taking the major power role.

We've already shown it to have a better EROEI than fossil fuels, even when favoring the fossil fuels with less stringent EROEI calculations (i.e. not counting embodied energy of equipment). If PV has a EROEI of 15 (minimum), and since the fuel/sun is a free resource, its energy output can replicate itself by x^15. Hardly a problem

(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.

(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.

(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.

(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.

Get as many Submarine StandBy Batteries as needed to run this for the expected period of time. (months, years...)

Now you have the Rack powered with no external wiring!