Can a single survivalist in a post-apocalypse, post-EMP world have electrical appliances?

Question

EMP has wiped out every electrical circuit on the planet (Carrington event level). At the same time some unspecified non-persistent major disaster has wiped out everyone on Earth except her. There's no major threats to her, she's just living her life in solitude raiding supermarkets for canned foods, toiletries, and casks of water. And raiding other stores for anything else she needs to survive.

She is a survivalist, street smart, and she's managed to salvage some solar panels, a small wind turbine, and some car batteries.

How likely is it that, after some setup, she is able to come home to the luxury of modern appliances? Is there any way she can have lights in the evening? Light switches in the wall? Washing machine and dryer? Microwave? Fridge? Freezer? Hot water? Air conditioning?

I understand petrol won't last so generators are out of the question, and all high tech appliances with ICs will be fried, including solar inverters, charge controllers, and wind inverters, so I can't see her generating 110V wall power. But is there any way to get some familiar luxuries in this environment?

Answer 1

It's plausible to get a nice life.

First: Wind Turbine
Don't bother, unless you can raid an electrical parts store and know how to build the complex circuit from memory. You'll need a bridge rectifier and a boost converter minimum. And that doesn't have the electrical safety brakes to stop the thing blowing away in strong winds.

I have a half an electrical engineering degree and even I'd put it off till last.

Solar panels - the tyranny of MPPT
First - try to find a solar inverter in a box somewhere that survived the EMP. They may survive depending on packaging or orientation. That will make your life so much easier, basically this becomes plug and play.

If you can't You're not going to be able to get the most efficient use of your panels, but you can still use them.

Manually calibrating solar panels to run without an inverter
Try to get an analogue voltmeter from an electronics store. A multimeter in packaging and turned off and packed on the shelf will probably survive an EMP and is preferred, but analogue will do. You need to take some precise voltage readings from your solar panels at different orientations at different times of the day.

The panels on your roof are probably wired in series, trying to get as high a voltage as possible for an inverter, which is now completely fried. My 15 panels would put out ~300V DC / 0 amps open circuit, ~150V DC / ~8 amps if short circuited, and have an optimum max wattage somewhere in between, depending on the exact time of day and cloud levels. Your solar inverter will do a non-trivial thing called MPPT to find that optimal level.

In battery systems the inverter will have a charger, which detects the battery condition and converts the power to the optimal required for charging. My battery system needs 14.6V for the bulk of the day, and 13.7 when the battery charge level gets above about 80%. The battery charger will also cut the connection to the solar cells at night, as solar cells connected to batteries at night will drain power.

Without any clever electronics, you need to make sure that your solar system puts out these optimal levels for your battery. So by re-arranging your solar panels from serial to parallel wiring you can tweak those power curves. 15 cells put out say 300V in series, 15 in parallel will put out about 20V at a higher amperage. If you raid an electronics store for a big diode, or just have a switch you flick at night, you can stop the panels leaching power overnight, or during clouds. You'll need to make the wiring beefier too.

If you're getting close to the right voltage but are just a little over then changing the angle of the panels to the midday sun will change the power point. You're better off being under the optimal voltage (so it wont charge or charge slower than expected), than over (which will evaporate the acid in the batteries).

But before you rewire your panels, you need to think about your battery configuration. I'd suggest go for existing 12V camping stuff rather than try to drive your washing machine with a DC motor at 80V kinda thing, but you may need to think outside the box here.

Batteries
You're better off raiding an auto-parts store for fresh batteries than salvaging from cars. SLA batteries are ideal as they wont need topping up with demineralised water. Get as many 12V batteries of the same kinds as possible and wire them in parallel.

Lights
Incandescent bulbs will run on DC just fine, just if the voltage is lower they'll be a lot dimmer. Compact Fluros need a non-trivial circuit to run on DC, so wont work. This style of modern LED bulbs are amazing - they run from 250V down to about 60V at a constant brightness, AC or DC.

If you have these bulbs (or take them from the shop), your bulbs can run on as low as about 60V DC. However this may be a bit too high - these bulbs will fit in existing wiring and sockets and run on 12V. What voltage you run on depends on your most power-hungry appliances, your white goods.

Light switches will work if the power flows through them.

White goods I've seen a washing machine with a DC motor, so you could theoretically hack that to work, however you're better off raiding a caravan manufacturer or camping supply store for these. Some caravans have built in 12V washing machines.

Big, family-sized heat pumps (fridge, freezer, air con) are almost always AC and wont work. However DC models for caravans do exist and can be salvaged. You can also get camping fridges and freezers that can run on varying DC voltages. Often these camping fridges can run between 9V and 30V fine.

You can get a 12V plumbed in water heater from camping stores, and a 12V constant pressure pump to pump from your tank to your existing plumping.

Electrical safety
You need to connect the battery into your lights and through your house. I'd suggest through the existing power box, although there are other ways.

Your existing fusebox (at least the Australian standard one I'm familiar with) is not going to like DC at all. The RCD wont be reliable, and the circuit breakers wont trip when overloaded. You'll need to rip this all out, and replace it with 12V circuit breakers. I've seen replacement ones that fit in existing fuseboxes for 12V, however you probably wont be able to find these at every electrical store, just any old 12V DC circuit breaker will do - basically a car electrical fuse box will do the job.

Connecting it all

• Cut your houses power main with pruning sheers or the like (you don't want to start a fire somewhere far away)
• Disconnect every electrical device and light bulb from your place.
• Obtain 12V fridge, freezer, lightbulbs, aircon, washing machine, hot water system from camping stores or caravan manufacturers.
• Set up your solar panels such that they provide, say 14.8V in the midday sun.
• Set up your batteries in a ventilated area.
• Put a night switch or a diode between the panels and the batteries.
• Run wires from the batteries to the power in in your fuse box.
• Connect it all.
• Measure voltage at light socket outlet. 14.8 into battery should be about 13.5V though house wiring at the socket. Turn light switch off. Insert 12V bulb. Turn on, tada! light.
• Install other 12V devices over time.

Answer 2

First of all, generators are not out of question. Running some lights, a wash machine, a fridge and a boiler to have hot water doesn't require that much power, and doesn't requires it continuously, apart maybe for the fridge.

So, a tank station can supply fuel for quite sometime when it comes to run a small power generator.

More importantly, having grown up spending the summer in a farm with no electricity, I can ensure you that one quickly adapts to living without those "luxuries": one can get warm water by letting a bucket under the sun, using a fire or even using some black paint and a hose, a fridge is not needed if you don't have leftovers to store (and with no supermarket around I doubt there will be leftovers), and a candle or a petrol lamp is enough for the night, much more easy to turn on than a power generator.

Answer 3

Even a massive EMP won't fry everything - electronics in Faraday cages will survive. That is everything with metal covering. I am not sure about microwave ovens, but they seem to be fairly well covered.

Anyway, hunt for older equipment (without electronics), and some aspects have been covered already. However, there are quite comfortable alternatives without electricity, and they are even better suited for gridless operation than trying to run a generator:

• Gas operated refrigerator (patented by A. Einstein) - a bottle of propane gas can operate it for years. Used mostly in camping scenarios. Find one without IC controller.
• Carbide lamp is safe, needs just water and carbide (and that stores well).
• Gas camping stove can be used for cooking (maybe even using the same bottles as the refrigerator). Slightly less comfortable than a microwave, but not by much.
• Gas operated portable water heater for showering. Or just do not shower that often during winter, it is not like you are going to meet anyone soon...
• Gas operated air conditioning exists, but likely uses IC controller. Might be difficult to set up. But instead of air conditioning, I'd suggest moving to a climate zone with mild summers and mild winters.

Answer 4

Camper Time!

Your heroine might want to consider investing in a nice recreational vehicle or camper. All this assumes you are able to obtain working motor vehicles after the events of your story. The heroine in the book Emergence found herself in a similar situation, and got herself a camper to tow behind her vehicle. These self-contained, almost-always off-line portable luxury homes allow a body to travel in the lap of luxury, with a wide range of built-in conveniences that are usually designed to work either with or without a power grid and a gasoline supply.

The RV is almost universally a gasoline-powered vehicle, so if you are worried, go with a camper and make obtaining an alternative-fuel truck a priority.

Fuel can include tapping into natural gas supplies and propane tanks, so "fuel" can be applied pretty broadly. If you've ever done much camping, there are many kinds of stoves and refrigerators that use "gas" directly, most have built-in toilets, and certainly campers can be very luxurious and have solar panels, battery systems, etc. Plus, campers are portable, so your nomad will be able to wander around when the local stores are looted out to get more supplies. Why abandon all the luxuries of home when you're on the road?

All the appliances in these things are off-grid type equipment, if you pick the right one. Do a search for campers and you'll be blown away by these luxurious monsters.

Answer 5

You have to look at the timeframe and the required power.

• I find it hard to imagine an EMP that kills all technology yet leaves even one human alive. What about components in metal shipping containers (Faraday cages)? Components in military storage bunkers? So assume that any desired parts can be found, they are just not assembled yet. Anything that was plugged into a power grid at the time of the event can be fried if you want that.
• You are correct that gasoline does not last very long. But gasoline is not the only fuel for internal combustion engines. Vegetable oil. Wood gasifiers.
• For that matter, break into a museum and get a steam engine.
• It will be a challenge to generate a predictable voltage which does not fry the appliances. Batteries as intermediate step might help here.
• For the really long term she will have to think about where she lives, and that affects available power sources. Hydropower? Wind? Cutting and burning wood?

If you worry about gasoline going bad, remember that canned food won't last forever, either.

Answer 6

I believe others have answered sufficiently that yes, electricity is possible - and also have given conditions.

Your story's premise is of course very interesting in the sense that a lot of the conventions, limitations, values, laws, taboos, etc. of our current world fall away (which gives a lot of room to explore assumptions that we take for granted in our current world). So a lot of what we consider luxuries or necessities will probably also follow that route... The character has almost infinite resources both natural and manufactured, almost limitless access to housing, land, climate, geography, ... and freedom from all social constraints.

One of the things that may fall away is electricity. Agreed, today it is cheap, energy-dense, easily distributed, and a lot less polluting than e.g. wood fires. But in a world where you are the only human, have access to all the forests you could wish for and your hearth's smoke output is a drop in the bucket compared to natural processes, wood would make a much easier to use energy source (on the individual scale). Remember that in less population-dense, technologically less-advanced ages humans also liked to live in comfort and in fact developed a lot of techniques for doing so.

• heating/cooling/AC: apart from the wood-burning fire place, people lived in caves or other structures that made use of the temperature-leveling properties of massed earth, see e.g. wofati, Earth shelters and Earthships for modern incarnations. People in desert climates used evaporative cooling, and developed solar chimneys and other techniques to use convection to draw in cool air and expel warm air. Your heroine also has all the freedom of movement in the world and can move (permanently or seasonally) to almost any climate she fancies.
• lights: why any need to stay up late and not go to sleep as soon as the melatonin kicks in naturally? There's no deadlines or rush hour to beat, no TV shows to watch. What's wrong with fires and candles or watching the moon and stars?
• laundry: no need for clean or wrinkle-free clothing, who you're gonna impress? If you want something new or clean, why, there's probably some stores close enough by that have more than you'll ever need in a lifetime. Come to that, why not move to a suitable climate and forego clothing altogether (or for the most part)?
• Fridge/freezer: again why? One can get all the dry and canned goods one desires from the supermarket, hunt whenever the need arises, or just go out to the veggie patch and harvest what you need. Leftovers are simply returned to nature for recycling. That said, previous humans had to contend with seasonal changes, droughts, expensive energy expenditure. They developed techniques to dehydrate and ferment foods to preserve them (apart from vegetables and fruit, also meat (think jerky or pemmican) and dairy (cheese etc.).) They hauled in ice in winter and stored it in cellars or ice-houses for months. They used primitive evaporative cooling fridges. And yes, my grandma had a fridge that burned paraffin to cool (we converted it to electricity by replacing the flame with an incandescent bulb, I think it may still be in use somewhere).
• cooking: barbecue every day :-) (Well, cast iron skillets and dutch ovens also work well.)
• water heating: can also be done on a wood fire, or a simple solar setup. Or move close to a geothermal well. Or stop washing so much, as some people have done in modern times.

One resource that might give you a lot more ideas is permies.com ("Permaculture and Homesteading Goofballs"), which cover a lot of off-grid living necessities and luxuries. It is online, but I think Paul Wheaton and some of the other names behind it have also published paper books, which may come in handy once the internet is fried by your EMP.

Come to think of it, once the EMP fries everything, public water supply and sewerage treatment will cease to exist too, and that combined with all the dead people will be a real health hazard for a time. So an off-grid, self-sufficient homesteading lifestyle will probably look very close to what your protagonist will be doing.

Answer 7

You can't 'salvage' complex electrons after a major EMP event

Modern electrical appliances (anything with a chip) wont survive such an event anymore than they'd survive a flood or house fire. To begin with any devices you want to save would have to be off line (disconnected from the power grid) at the time of the event. And, depending on how powerful the event was that would only save simpler devices like electric motors and/or basic household appliances like heaters and toasters etc.

Virtually any modern electrical device not hardened to military standards would fail unless insulated from the event i.e. it needs to be placed in a Faraday cage - for civilians being wrapped in multiple layers of heavy duty aluminum foil should suffice.

The thing is retrieving devices like solar cells after the event wont do you any good. You need converters and batteries as well. Unless the devices your character finds have been off line at the time of the event and stored in a location that somehow shielded them from the worst effects they probably would have been damaged.

Your best bet is to make her/him/it either a 'Prepper' who as a precaution has stored equipment and supplies away in the event of emergencies, part of a military unit that had access to such equipment or a competent electrical engineer who can build basic devices from spare parts.