An introduction to electricity

If you know the ins and outs of electricity feel free to skip this section.  For the rest of us mere mortals I’ve written an introduction to electricity and concepts that are important to us.  To help us understand a bit, I’ll compare it to water going through a hose.  Warning:  This is a simplistic but sufficient explanation!

There’s three things that are important for us to know about:

Current

Electrical current measures the  rate of flow of electrons in a circuit and is measured in Amps.  In our water analogy, it’s the flow rate of the water.

Voltage

Voltage measures the amount of electrical potential.  In our water analogy, it’s a measure of how much water pressure you have.  For most applications, voltage doesn’t change much.  Common voltages for emergency power systems are 220/240, 110/120, 24, 12, and 6.

Power

Power is how much electricity you’ve used up.  When you see Watts or VA referred to on an appliance tag, it’s talking about Power.  In our water analogy, think of the total volume of water transferred.

Ohm’s Law

A fine gentleman named Georg Ohm discovered a relationship between these three measures.  Nowadays we call this Ohm’s Law.  Simply put, the equation is P = VI.  In non algebraic  terms, it means that Power = Voltage * Current.  The main thing to take away from this is that for any given load, as you reduce voltage your current goes up.

Putting it All Together

If you have an appliance that uses 1100 watts of power at 110V it will pull 10 Amps of current. If you run it off an inverter hooked up to a 12V battery,  it will pull 91 Amps.  YOWZA!

In our water analogy, think of your common 1/2″ garden hose.  The water pressure (Voltage) doesn’t change.  If we grab a stopwatch and figure out how much time it takes us to fill a five gallon bucket, you get a rate of water flow (Current).  If you swap that hose out for a 1″ diameter hose and measure the fill time now, you’ll find out that your water flow rate (Current) has changed even though pressure at the spigot (Voltage) and the size of the bucket (Power) haven’t changed at all. If it doesn’t make total sense yet, that’s ok … read on, we’ll have some practical application down below!  If it STILL doesn’t make sense after that, then ask in the comments or email me and I’ll clarify.

First, we need to think about what we want to use power for

Lights, heat, cooking, tv, fridge, power tools, all that stuff, right?  Nope, you need to pare it down.  Think about what you need to have power for vs what is just nice to have power for.  Heat, for example, isn’t a great use of stored power.  Lighting can be, but you can also get light from lanterns, candles, and the like.  Cooking can be done on a propane grill, camp stove, rocket stove, and other such things.  Here’s what I would use power for.

Short Term Appliance Usage

For short to medium term emergencies you’ll want to be able to keep your fridge and freezer going every few hours to keep stuff cold and frozen.  You may want to wash a load of clothes from time to time.  Or you want to use the Kitchenaid to process some food.  You get the idea.  The key here is to remember to be frugal with appliance usage because these things can eat up power like there’s no tomorrow.

Rudy’s Tip: During an emergency you can run your freezer or fridge for a few hours a day and things will keep nice and cold as long as you try not to open it too much.  Chest freezers are far better at staying cold, and so are full freezers.  The amount of time you need to run your fridge will vary based on the weather.  If it’s summer in Arizona you may want to forget this plan completely!

Lighting

I wouldn’t suggest running standard incandescent lights off of an emergency power system.  Using LED based lights can significantly reduce your overall power usage.  Look for bulbs and fixtures that are designed for RV use.  Using candles and lanterns for lighting is also a good idea.

Charging Batteries

You’ll want to keep batteries charged up as best you can.  You DO have a stash of rechargable batteries, right?  These can be used in lots of different things.  Flashlights, radios, GMRS type walkie talkies, you name it.  Don’t forget to charge IPods, portable video game units, etc to keep entertainment options open.

Rudy’s Tip: Some batteries can’t be safely charged on cheapo inverters.  Some chargers require a proper sine wave to function.  Most inverters have a modified sine wave.  More about this later, but keep it in mind…

Tools

Using power tools can seriously improve your effectiveness when you’re working around the house.  Using a circular saw to cut plywood to protect your windows is far more efficient than using a hand saw.  Well worth the power usage.  Be prudent, but smart.

Components to an emergency power system

There are three main components to an emergency power system that we need to consider:

Power Source

During a grid up situation we obviously have grid power.  If the grid goes down, our power can come from our power storage system, a generator, solar power, or any combination of the above.  Since the power storage system can’t replenish itself, we need a power source that can fill up the storage system and ideally also be used for a power source directly.

Rudy’s Tip: For me, a good generator fits the bill here.  I don’t have enough sun year-round to count on solar for anything but extra candy on top.  Things I look for in a generator are remote start, efficiency, and either diesel or propane operated.

Power Storage System

This isn’t an absolute requirement, but it’s definitely a recommendation.  You should have a way to store power for later use.  Generally speaking you’re looking at a bank of batteries with an inverter to convert DC to AC and a charger to top off the battery banks from our power source(s).  You need to know what you want to drive off the storage system in order to properly size it.  More about this later!

Rudy’s Tip: You should avoid using auto batteries for your battery banks.  Look for deep cycle batteries which will stand up to hundreds of charge cycles before losing capacity, vs tens for a car battery.  Your best bang for buck will normally be with 6V batteries designed for golf carts and the like.

Power Distribution

This can be as easy as a few extension cords and as complicated as secondary electrical wiring in the walls of your house complete with emergency lighting.  Go as hog wild as you want here.  I recommend using extension cords for most applications, but if you have an opportunity to run dedicated wiring it’s well worth having emergency outlets in every room.

Rudy’s Warning: Stay away from transfer switches that will switch your entire house between grid power and your own system.  It’s really easy to drain your storage without even noticing until it’s too late.  The average house has so many different things plugged into the house that we don’t even think about or notice.  This warning doesn’t apply if you are doing a major power storage system or if you’re doing whole house solar, etc, but if you’re doing that then you probably don’t need this how-to!  Feel free to email me or ask in the comments if you want more information on this!

Sizing your system

First, you need to decide what you’ll run off of your storage system vs what will only run when there’s an available power source.  For example, I would recommend you not try to run major appliances off of your battery banks.  Plug the freezer and fridge directly into the generator and operate them that way.  Major tools and such I would recommend doing the same thing with.

That said, let’s take a super simple system that my reader was asking about.  She wanted to be able to run her crockpot for ten hours a day, have some 24 hour lighting available, and a bit of extra just in case.    All run off of the battery storage system which is replenished from a generator.

First things first, we need to know how much power these things burn up.  This is easy if we’re provided with the power draw by the manufacturer, but if they only provide us with current draw we can calculate power as well.

For lighting, let’s figure she’ll want 10 bulbs.  If you buy CFLs you can get the equivalent of a 100W incandescent bulb that only uses 23W.  Fantastic.  So for lighting, your overall power usage is 230W.  Realistically you won’t have them all on at once but let’s be conservative and say we will.

Unfortunately the crockpot doesn’t tell us how much power it uses, but it does say that at 120V it will use 2A.  Since we know P = VI, we can calculate the used power as 120V * 2A = 240W.  Fantastic.

Rudy’s Note: Battery storage capacity is measured in something called Reserve Capacity and is defined as the length of time in minutes that the battery can power a 25A load without the available voltage dropping too low.

Since we know how long we want to power these loads, we can calculate the amount of Reserve Capacity (RC) we need for each load.  The formula used for this is RC(in minutes) = Run Time (in hours) * Wattage / 4.545 … the 4.545 is a conversion factor, just in case you were wondering.

Lighting:  24 hours * 230W / 4.545 = 1215

Crockpot: 10 hours * 240W / 4.545 = 1268

Total RC Required:  1215 + 1268 = 2483 minutes

If we go get a bunch of 12V batteries with a RC of 200 each, we’ll need 13 batteries total.  As always, we want to buffer this a bit, so call it 15 batteries.  Even a small system like we’ve outlined can be a large footprint and can start getting rather expensive.

To keep these charged, we’ll want to get a trickle charger that can keep them topped off while on grid power and that can be plugged into our generator for top off during emergencies.  We’ll need to have a power inverter to convert the DC power off the batteries into AC power that our appliances can use.  Power inverters have an input voltage (in this case we want 12V DC) and an output voltage (in this case we want 120V AC) and are rated for certain loads.  Generally speaking inverter specifications talk about peak and sustain loads, and they are measured in Watts.  In our case, we need an inverter capable of at least 500W, better to get one that’s bigger than that.

Rudy’s Tip: Get a charger that is a multistage smart charger.  This will prevent your batteries from being damaged by overcharging and will optimize the speed of charge.

Finally, you’ll want to size your generator appropriately.  We’ll assume that we want to run a fridge (600W) and a freezer (800W) off of it, charge our battery bank (800W) for a total of 2.1kW.  Buffer it a bit and you want a generator capable of at least 3kW sustained load.

To recap, to cover the needs of this system we need a good charger, an 800W inverter, a 3kW generator, and 15 200 RC batteries set up in a single battery bank.  Estimated street price as I write this right now is about $2500 for the major components, not incuding wiring.  Seems a little expensive to run a crockpot!  But you get the idea.

Rudy’s Disclaimer: This is not intended as a recommendation on exactly what you need to build.  You need to design a system to your own needs, and not to the needs of one of my readers.  I’ve intentionally left out technical details and in some places cut some corners.  You should research further before building your own system and potentially seek expert assistance.  The goal of this post was to get you thinking about it, and to prod you to decide if it’s something you really want to do.  That said, I’m willing to talk a bit more about this in depth if it’s something that you guys want … let me know!

We all want to have power all the time, and if you’ve gone without for an extended period of time then you already know how important it is to actually have power on.  We cook with it, we use it for light, sometimes heat, and for all around comfort.  That doesn’t even begin to cover things like entertainment, luxuries, etc.

How do I get power when the grid is down?

Pure off-grid solutions are out of scope for this post.  So I’m not going to talk about whole-house solar, wind, water, etc.  I’m going to talk purely about what is available to your average suburb resident.  Realistically there’s just three easy ways to get power when the grid is down.

Grid Power Storage

This is basically the concept of putting together a bank of batteries with a trickle charger, keeping them topped off via grid power when it’s available, and then using the stored power via an inverter to run whatever it is that you want to run.  This is a reasonably viable solution, but it has two major drawbacks.  First, batteries are expensive.   They’re heavy, and a pain in the butt in general.  Second, if the grid is down, and you run out of power, you’re done.  No more lights!

Small Scale Solar

You can use a few smaller solar panels to generate some power when the sun is out.  If the sun is out.  And if the angle is right.  And so on.  Solar power is somewhat complicated, requires some extra equipment, and by itself doesn’t have any method of storing the power that it generates.  You can certainly couple this with your grid power storage solution above, and use the solar panels to charge the batteries.  This can be a fantastic solution if you’re in a sunny area where you can be reasonably sure that you’ll have sun most of the year.  It’s not a very good solution at all if you live where it rains and snows a lot.   I’m sure you guys can figure out why…

Generator Power

I’m sure you all know what a generator is.  You can get them in all sorts of shapes and sizes.  You can get them with all different types of fuel types.  Overall, this is my personal preference for raw power generation.  You can get a fair amount of on-demand power with the generator running, and you can use the exact same trickle charger you use to store grid power to top off storage batteries.  Some generators can even charge batteries directly.  Fuel is generally not that hard to store, and it will keep for a while.  If you get a propane generator you can even use the same tanks you would use for your gas grill on the back porch.

Rudy’s Recommendation: My personal recommendation is a properly sized grid power storage (lots of batteries) coupled with a properly sized generator.  My preference in generators is diesel fuel with attention paid to overall noise reduction.

What should I use my stored power for?

Movie Night!  Just kidding.  I’d suggest thinking ahead about what you’d use your stored power for.  Lights are a good choice, cooking can be too.  I’d use generator power but not battery power to keep food in a fridge or freezer cold. Running your electric baseboard heaters is probably not the best idea.  Overall, you want to think ‘comfort’ but not luxury.  Also think about efficiency, etc.  Deciding ahead of time what you’re going to use it for is critical to proper sizing of a power storage system.

Rudy’s Tip: Even though I say to think comfort and not luxury, in an extended grid down situation cabin fever can set in rapidly.  It’s well worth using some fuel and generator power to let the kids play video games or watch a movie from time to time to keep spirits up and prevent people from going crazy.

How do I put all this together?

I thought you’d never ask.  I’ll have a post on Friday that discusses the details of a generator backed grid power storage system with a specific ‘How To’ approach.  I’ll talk about what to use it for, sizing a system appropriately, figuring out how many batteries you might need, the whole nine yards.

If only all zombies were this suave

I know, now you’re thinking … I know WHY I should prepare.  It’s blatantly obvious!  But what I DON’T know is what on earth I’m preparing for!  The answer to that question should also be pretty obvious.  We’re preparing for the invasion of the Zombie Horde!

Yes, I have a soft spot for zombies and zombie movies and zombie action figures and and and…. In any case, my wife puts up with more than she should!  I’ll try to restrain myself here as best I can.

In my mind, too many people are focused on the equivalent of a zombie invasion.  Whether it’s the end of the Mayan calendar in 2012, or an asteroid ala Armageddon striking the planet, too many folks are focused on the huge planetary scale events that toss us back to living in caves and hunting food with pointy sticks.  Don’t even get me started on the ‘Day After Tomorrow’ global warming crowd.

Don’t get me wrong, I love disaster movies just as much as I love zombie movies, or at least almost as much.  But I do think that preparation is a more serious issue and is something worth being a bit more realistic about than the latest Hollywood blockbuster movie.

I approach scenario planning a little more differently than some.  I try to categorize scenarios based on Scope and Duration.  This allows me to prepare along two different paths at the same time, as opposed to just trying to put away a year’s worth of food and water or whatever.  Scope and duration both get worse the farther along you get.  It’ll make more sense if you look at what these classifications are.  I should also note that these are MY classifications, and you should feel free to adapt them based on your personal bias and opinion.

Scope is really the reach of the zombie invasion.  How broad is the impact?  Who is affected by it?  For scope, I use the following classifications:

• Personal - Something that affects you and your immediate family.  Generally not something that touches people outside your family.
• Vicinity - I define vicinity as your neighborhood, town and, like the word implies, your immediate vicinity.  Note that your vicinity can migrate with you if you’re travelling, or you’re at work, etc.
• Region - This would be a metro area, county, state, etc
• Country - We all know what this is
• World - Hope you enjoyed Armageddon, though Deep Impact was more entertaining…

Duration is pretty straight forward.  I classify Days, Weeks, Months, Years, and Generations.  I don’t think this requires all THAT much explanation.

Taking a few examples, a power outage due to a storm would probably be a Vicinity scoped event that last a few days at most.  On the flip side, your house burning down would be a Personally scoped event that would take weeks or months to recover from.

Before you can categorize scenarios, you need to actually HAVE scenarios to categorize.  For your reading pleasure and convenience, I’ve listed a few at the end of this post.  However, scenarios are an intensely personal thing, and you really need to take a look at what could go wrong in your life and plan for those scenarios accordingly.  While many things are fairly universal, there’s always a few potential disasters that are unique to your own circumstances.

So now you have a list of scenarios with potential scope and duration defined.  Congratulations, this is your first list out of many.  Now what?  How do we decide what to prepare for first?

Well, the good news is that if you approach preparedness in an intelligent fashion, you’ll find that by preparing for a couple of disasters, you end up increasing your overall preparedness level which sets you up better for those other disasters that you didn’t prepare for specifically.  I know, seems pretty self evident, but it’s worth repeating because chances are that list you have is pretty daunting and you might be wondering how on earth you can plan for all of that.

In a nutshell, you want to order your list by the likelihood of the scenario occurring.  So go back to your spreadsheet, add a column for likelihood, and sort by it!  Voila, there’s the order that you prepare in!  No, it’s not quite that easy, but you get the point.  The bottom line is that you want to be prepared for losing your job, or being out of power for a week, or being quarantined for a month because of the latest Swine-Monkey-Bird Uncommon Cold before you prepare for Halley’s Comet striking the planet.  Besides, you have until 2061 to prepare for that.  The zombie apocalypse is next month.  Art Bell said so!

I also think it’s better to focus on shorter duration preparations first, and build up to longer duration events.  It would be rather daunting to try to put away two years worth of food and water all at once, but it’s not at all that bad to go from two weeks worth to a month, or one month to three, etc.  Back to the whole ‘preparing for one thing prepares you for others as a fortunate side effect’ concept.  Similarly, focus on the basics first, then expand.  Be patient but persistent, you’ll get there before you know it.

Finally, and most important of all, you need to figure out where your personal “good enough” point is.  This is another intensely personal issue and you need to decide for yourself.  Some people will want to prepare for the next Ice Age, but I think they’re few and far between.  Be realistic, be honest with yourself, and decide how far you want to go.  And never forget that while you’re preparing to survive the zombie apocalypse, it’s not here yet and you need to live in the here and now, not always in the What Ifs.

Read that again.  YOU are responsible for your own well being.  YOU are responsible for your family.  YOU are responsible for your mother in law (Sorry guys…).   But there’s a critical problem here.  It’s not in style right now to be responsible for yourself.  The culture we have developed here in the United States has gone from a self sufficient independent life style to one that is a dependency oriented life style.

Look around your life today.  Chances are that most of the people you come into contact with on a daily basis are simply living their life on autopilot.  For most of them, things are going reasonably well.  After all, even if you’re “poor” in the United States, you’re rather well off in terms of how the rest of the world lives.  I don’t say this for self righteous reasons.  Quite frankly, I enjoy my luxuries just as much as the rest of you.  I like being able to run down to the grocery store and get some bizarre food item I happen to be craving at the time, or picking up the latest and greatest gadget at the local electronics box store.

Most of the people around you depend on The System far more than they realize, and chances are, so do you.  Therein lies a critical problem.  When things don’t go perfectly, and sometimes even when they DO go perfectly, those things we are dependant upon just aren’t there.   Or they’re late.  Or you don’t get as much as you might have hoped or planned on.

Maybe you lose your job, or maybe foul weather hits.  We’ll talk about WHAT we’re preparing for in another article.  Just assume for a minute that a Bad Thing happens to you.  Now what?  If you’re like most people in this country, you’re going to wait for the government to step in and help.  After all, that’s why we pay taxes, right?  They just HAVE to come help us!  Sure, they’ll show up.  Eventually.  Problem is, you’ll probably be up a creek until then.  Having worked for the government, they are SLOW.

Like I said above, it is YOUR job to be prepared.  You don’t need to prepare for an asteroid hitting the planet if you don’t want to, but taking an honest look at your life and deciding what sorts of Bad Things are likelier than not to happen is a fantastic idea.  But when I see supply problems at the gas station on the corner or the empty grocery store shelves after a winter storm it just reinforces the need to prepare.

At the end of the day, it comes down to a choice to take ownership of your future, and prepare for things that have a reasonable probability of occurring.  If you’re prepared when it happens you will be far more likely to ride it out in reasonable comfort or security.  If you’re unprepared, well, hopefully you don’t end up like these folks…

People seeking refuge in the Superdome from Hurricane Katrina