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I know this can vary from area to area, but in general how long does it last in your campaign?

I generally have used 1d6+2 days for most areas. Areas with solar or wind power would last longer? If nuclear plant is powering area I have generally used 1d6+2 weeks.

Would like to hear some other thoughts and ideas.

Also, I'm not to hip on how long Internet, cell phone and satellite commo would last without human assistance. I do know that orbits deteriorate and need adjusting form the ground.

All this is depends on if there is any damage at the power centers due to fighting or Zombies bumping into the wrong panel/switch.

Thoughts? Comments?

I'd would say anything from 24-72hrs before you'd lose power most places. Even with extensive wind/solar in an area the issue is that most grids are pretty extensive, so once the traditional power plants cut out, the whole grid would go down. You'd still have things hooked to the grid trying to pull power, but not enough inputs in to the grid to power them. It wouldn't matter if you are 200yds from some big 500kw wind turbines that are spinning full speed. If there is 10MW of power input to the grid, but there is 20GW of drain, the voltage on the grid is going to be too low to power anything. Now if you could isolate the grid in your area so that only the immediate area was attempting to draw on the generation of the local renewables, you could have a working grid...but with the big regional grids we have today, the draw would just be too big.

Nuclear power would go down as soon as conventional power plants. Most/all nuclear power plants cool their reactors using power off the grid, not self generated power. So as soon as enough conventional power plants went off line that grid voltage dropped too far and the grid started shutting down and brown outs, emergency cooling would kick in on the nuclear power plants and they'd go off line.

IIRC most cell sites, internet data centers, etc generally have reserve power for anything from 12-72hrs without human intervention (like refueling onsite generators and stuff). So as soon as the power grid went down, supposing bits you are using to connect to parts of the internet had backup power, and most do, the internet itself would go down in parts starting within about 12-24hrs and it would be completely dark within 48-72hrs at the most beyond that.

Satellite com would be down as quickly as the powergrid/internet. Satellite com relies on base stations on Earth to pass messages around, it isn't simply satellite to satellite back down to another satellite phone.

Figure EVERYTHING is effectively dark within 1 week, and most likely within just a handful of days.

Of course there would be some pockets of power. Some buildings, especially some houses, have solar power and some have battery backup with solar power. Once the grid goes down they'll go in to independent generation mode, so at least when the sun is up the building would have power, and if there is a battery backup the building would have power 24/7 depending on how the battery backup is sized.

There are also some street signs, road markers, street lights (not many of those, but a few. My office about half of the parking lot lights are solar powered) and some other stuff that is exclusively solar powered with battery reserve for night time/overcast conditions.

In general though, the world would be dark within a few days.

azazel1024 Thanks for the info. So, a good random roll for total power failure (save few exceptions as mentioned) would be my use of 1d6+2 (3-8) days?

Thanks again

Not completely unrealistic, but I'd go with 1d4+2 days.

azazel1024 wrote:Not completely unrealistic, but I'd go with 1d4+2 days.

Thanks

1-2 weeks for national power grids. Small communities that have local power, maybe a week longer. But the big thing is, once the humans go, the power falls rather quickly.

It would depend on the kind of Wave in the game world. If it's a fast wave, like in the Rifter versions, one to three days of electrical power, a week tops. However, if it is a slow conventional wave where people start getting sick en mass then you could have power for longer. I'm sure the power companies have an action plan already detailed for the event of a pandemic situation (Read: Get the hell outta dodge!).

Thanks all for the input and comments.

There are also propane communities. They run on large tanks buried in the ground. It could last for a while with no people actually using the supply. It depends on where the community is and what season the wave happened in though (And how many things where left on). They are also typically in remote areas witch is a bonus. But it will eventually run out along with everything else that isn't solar, wind, or hydro. But even those systems require maintenance to keep running.

Thanks all

I was thinking for long term base of operations for power at a lake or river, would steam power make a come back? The need to cut wood and the smoke and steam cloud would give your position away.

Or the old water wheel rig at a water fall/rapid moving river could be constructed. Would not need the fire for steam, but not mobile as a steam engine could be. Plus, no noisy wood cutting and smoke/steam.

Either one could be use to recharge batteries as well as generate electricity.

Maybe even get some solar panels working as well.

Second point: You got your power source as above, how how many times may rechargeable batteries be able to be recharged? 12/24 volt vehicle batteries?

Of course this would have to be a very secluded spot with mild winter as the water source would not freeze.

More thoughts?

A properly running steam engine burning wood produces relatively little smoke. Look at how much smoke comes out of your chimney if you are burning dried wood? A little, but very, very little. If you burn green wood or high sap wood, then yes, you'll produce a lot of smoke. Some types of coal also don't produce a lot of smoke. Steam power is going to be somewhat noisy though. Steam clouds are only produced in open steam engines. Closed cycle steam engines produce no steam.

Batteries, it depends. Lead acid batteries can be "recycled"/reconditioned. It is not a super simple task, but the chemistry involved and "industry" to recycle lead acid batteries in to new ones is relatively straight forward. As for life span, a regular auto battery can handle 20-30% duty cycle a few thousand times. If you discharge them much more than that their duty cycle drops in to the hundreds or even dozens if fully discharging them. Deep cycle lead acid batteries can handle 70-90% duty cycles a few thousand times. Both are "time limited" within reason to about 10-20 years MAX no matter how little they are used and/or maintained. Generally much less with normal use.

Other rechargables, lithium ion and lithium polymere batteries typically can last around 500 discharges and/or 7 years under low use before you see capacity diminish significantly. That'll get you to around 60-70% remaining capacity. Double that before the battery is effectively toast (IE won't hold any charge).

NiCads are in the couple of thousand complete cycle range if charged and discharged properly (they are super annoying) or a few years (I think like 4-6).

NiMh are the best. Some of the recent chemistry ones can handle upwards of 1,500 full duty cycles before seeing a significant hit to their capacity and should last a minimum of 5 years and more likely 10-20 years of light use before the battery is "dead". The new hybrid cells can also retain charge for a really long time (much better than rechargable lithium ion batteries. Technically all lithium ion batteries are rechargable, but the button cells and "AA" type lithium ion batteries are NOT rechargable as they don't have an integrated charge circuit that prevents them from being damaged or overheated from charging. Rechargable ones have that built in to them...but it also causes self discharge at the rate of about 10-20% per month, non-rechargable ones self discharge at more like a couple of percent per month).

So long as you are cool with going low power, you can easily manage personal power consumption on very little.

As an example, my "backpacking gear" and portable electronics can easily be managed by a nice backpacking solar panel. The one I have my eye on is only around 2ftx1ft unfurled and can hang on the top of a pack easily. It has two AA battery slots in it and a USB out port to charge USB based devices (and can charge without sunlight drawing from the AA batteries in the battery pack). It can charge a pair of 2000mAh NiMh cells in about 6-7 hours of full sun.

I have an LED camp light that takes 4 AAA batteries and last 15hrs at full power or 24hrs at minimum power. I have an LED flashlight that runs on 2 AA batteries that lasts about 20hrs at full power and 60hrs at minimum power. I have an LED head light that lasts about 16hrs on 2 AAA batteries at minimum brightness and about 10hrs at max brightness. I have a nook simple touch that'll go about 40 days reading about an hour per day and has a 5.5wh battery in it. My cell phone has a 5.4wh battery in it and light use is about 5 days at 1-2hrs per day. My iPad 2 has a 25wh battery in it and that'll last about 10-14hrs of use or about 5-7 days with 1-2hrs per day. I also am looking at, but don't have a Steri pen for water purification. It can take rechargable CR132 batteries (which aren't common) and get 40-50 liters of water treatment out of them, or about 10 days of use for myself before needing to recharge.

So lets assume I am reading for an hour per day, using my cell phone for 90 minutes (off the rest of the time) and my iPad for 90 minutes. I also sterelize all my drinking, and for the hell of it, cooking water as well. Plus 4hrs of use of "lights", say 2hrs of camp light, 1hr of headlamp and 1hr of flashlight. That means I'll need to recharge my cell phone every 5 days, ipad 2 every 5 days, nook about once a month, camp light every week, head lamp about every 2 weeks and flashlight about every 3 weeks.

The solar cells will give me in effect about 5wh of power per day (two 1.2v 2000mAh cells charged to max per day). So I can charge the camp light (1.2v x 800mAh x 4) in a day with a little power to spare, the flash light once in a day, the head lamp in a little less than half a day, the nook in about a day or a little more, the cell phone in about a day, the iPad 2 in about 5 days (gulp) and the steri pen's batteries (3.7vx 900mAh x 2) in a little over a day. Really the only serious hog is going to be that iPad. If I use it a little less, I can easily handle the charging duties of everything else.

Heck, getting rid of the electronics...well lets keep the nook, great reference source being able to pack hundreds or thousands of books in something that size (survival guides, PDF atlases, etc...even if PDF viewing sucks) with awesome battery life, but keep the lights and steripen. That solar panel (foldable by the way) could easily provide for 3-4 people to keep batteries charge for everyone's lights and the batteries for the steripen charged up based on the water demands of 3-4 people.

Getting in to a "settled" life style and if you want the extra stuff, your power demands can sky rocket. Even then, if you have just a couple of CFLs or LED lights burning a few hours per day and some basics like maybe you want to run a small hot plate to heat things up/boil water occasionally you'll need a lot more power. That said, an 800w hot plate for 30 minutes per day is 400wh, and a couple of 13w CFLs for 3-4hrs per day is another 70-80wh. All you need is around 500wh to keep that up per day. With 5hrs of direct sun (about average most places in the world that isn't desert/equator and/or very high lattitudes in the winter) a 100w solar cell can handle that along with maybe a couple of lead acid car batteries (typical storage capacity of a car battery is roughly 400wh at 20amps (the slower the discharge, the higher the capacity), which gives you 800wh).

Now if you want electric hot water heating, televisions, computers, tons of lights, refrigeration, AC, etc the power demands skyrocket. Average single family home in the US uses about 1000kw/hr per month, or around 33kw/hr per day. You'd need about 6kw of solar power production to handle that most places (at 5hrs per day average, that takes in to account cloudy days, shorter days, longer days, etc). That is a LOT of solar panels. However, as mentioned, cut back to maybe just some basic electrical cooking (very basic) and a small amount of lighting, and a smallish solar panel and a couple of batteries can handle it. You could easily build a water wheel on a stream that manages at least 3-4mph of flow or a small dam with maybe a 2-3ft drop and and at least a couple of hundred gallons per hour of flow could easily managed several KW of power production. Enough for a lot of survivors if you keep power use low (basically just energy efficient lighting, UV water sterilization and maybe a bit of water pumping, for wells or pressurized water maybe), probably a group of 30-50 people.

azazel1024, Thanks a lot for that info.

http://www.straightdope.com/columns/read/2165/when-the-zombies-take-over-how-long-till-the-electricity-fails

This might be of use to you.