Conserving Power While Boondocking, Part 2

Following up on our previous post about Conserving Power While Boondocking — another major way to extend your power supply is to understand where the power goes.

The built-in battery monitor won’t help with that. You will need to install an accurate amp-hour or watt-hour meter that measures the amount of power being consumed in real time.

A good amp-hour meter with a digital readout (made by Xantrex, Bogart Engineering, and other companies) requires some installation and money, but for those who frequently camp without hookups it’s well worth the investment.

With a real monitor you can see what each light and appliance is consuming, and identify the big users so that you can avoid them or upgrade them. Right off the bat you’ll see that your RV furnace is a huge consumer of electrical power, so you might want to consider an extra blanket on the bed or even a catalytic heater (which uses no electricity). Incandescent lights (on older Airstreams) are also big consumers, so if you don’t have LED you should seriously consider upgrading the most-used interior bulbs or entire fixtures.

boondocking

Studying power requires you to understand just a little bit about how electrical power is measured. The amp-hour meter will measure the 12 volt DC power coming off the batteries (or going back in when charging) using amps. Constantly drawing one amp from the batteries for an hour will total one “amp-hour.” The meter will keep track of amps going in and out at any given time, and also keep a total of the amp-hours used since the battery was last fully charged.

(If you want to think of the power in terms of watts instead, just multiple the amps by 12. But for the purposes of this discussion we’ll stick with amps.)

A typical Airstream trailer comes with a pair of Group 27 batteries (that’s a physical size, not power capacity). They might each be rated at 85 amp-hours capacity for a total of 170 amp-hours. But because you should only discharge them to half of their total capacity (for longest life), your net capacity from two batteries is really just 85 amp-hours.

The furnace pulls about 7-10 amps while running, depending on model, which adds up to a lot of power when you consider how long it runs on a cold night. It’s one of the biggest DC power consumers in the trailer. That’s why setting the thermostat lower on a cold night will help a lot.

Just two nights of furnace can easily drain the usable capacity of the standard pair of batteries in an Airstream trailer. By monitoring the electrical “cost” of running the furnace with the amp-hour meter, you’ll understand what’s happening before the power goes completely flat.

boondocking

Why do trailer batteries go flat even when you’re not using anything? An amp-hour meter can help you understand “parasitic” loads on the batteries. Several devices draw small amounts of power even when they are not in active use, and that’s what we call a parasitic load. This includes the circuit board in the refrigerator, the propane leak detector, the stereo, the circuit board in the water heater, etc. All of those little parasites add up, and it’s not uncommon for them to total an amp or so of constant draw.

A one-amp parasitic draw means all of your useful power will be gone in about 85 hours—just three and a half days—even if you aren’t using anything else in the trailer at all! This is why Airstream provides a STORE/USE switch to cut power to most systems when the trailer isn’t being actively used.

With the amp-hour meter you’ll be able to see the exact parasitic draw and get an idea of how it combines with your routine power usage while you’re camping. Soon you’ll understand why there are so many posts in online forums from new owners asking why their battery was dead after just one night of running the furnace.

boondocking

If you frequently run out of power when boondocking and you don’t want to spend the big bucks to get a generator or solar panels, the easiest and cheapest option is simply add more battery capacity. There are several ways to do this, and the best solution depends on the layout of your Airstream. Usually people find a spot toward the front of the trailer (such as under a couch or in an external storage compartment) to install a bigger battery bank.

At the same time it’s an opportunity to upgrade to Absorbed Glass Mat batteries, which last longer and are safer than ordinary “wet cell” batteries. Going back to the electric car analogy, more battery power is like going from a Nissan Leaf (with an 80 mile range) to a Tesla Model S (230 mile range). Suddenly your “range anxiety” is greatly reduced and you can actually go places.

The larger battery option is less costly than a “quiet” generator or solar setup, with the advantage of always working regardless of sunshine or fuel supply. For most people, more battery capacity and better conservation are enough to get a few extra days of boondocking.

Knowledge is power, and in this case more power is mostly a matter of more knowledge. You’ve got options to explore. If you find yourself addicted to the off-the-grid lifestyle, congratulations! It means you’re enjoying your Airstream, and that’s a good thing.

Conserving Power While Boondocking

One of the most concerns of RV travelers who have begun to stray from established campsites has to do with energy usage. They’re always worried about running out of battery power, a version of the “range anxiety” that owners of electric cars often have.

That’s a legitimate concern, because once the batteries run out of juice, everything in the trailer goes off: refrigerator (even when running on propane), heat, light, water pressure … even the hitch jack won’t go up or down anymore. If it happens to you, you won’t forget it.

It’s a pretty traumatic experience to have the entire trailer—your home and security—go dead.

The battery life problem is two-fold. First, many owners really have no idea of how much power they are using at any given time (the built-in battery monitor is pretty inaccurate). Second, the batteries typically have just enough capacity for an overnight or a weekend if you aren’t running the furnace a lot.

Airstream provides those batteries because most people don’t use their trailer away from shore power for longer than a night or two.  Yes, despite all the discussions about “boondocking” you may have seen online, and all the blogs written by hard-core off-the-grid travelers, the reality is that most travel trailers go straight to a campground and get plugged in. Problem solved.

Boondocking Anza Borrego

 

 

Boondockers require more. After a while, a minority of owners start to pine for something more in their travel experience, and that inevitably leads them to the need for more power, more efficiency, and a better understanding of what’s going on.

Learn how to cut back on power; that’s the first and best way to get more boondocking time out of your batteries. Cutting back on use of electrical power gets into the same skills that boondockers need for water and propane conservation. You can do simple things like taking shorter showers (the water pump is a big energy consumer) and doing less dishwashing, switching to LED bulbs if your trailer didn’t come with them, setting the furnace temperature lower, etc. Conservation takes a little effort and a little practice, but it pays off immediately.

There are other ways to conserve as well. If you have an inverter, use it minimally because it’s a fairly inefficient way to power your devices like laptops. The inverter turns 12 volt DC power into 120 volt AC power, which then gets turned back into DC power by the “power brick” attached to your laptop. In each step, some energy is wasted—and even when there’s nothing attached to the inverter it is constantly consuming a small amount of power. Switch it off when you’re not using it.

More efficient devices are needed for boondocking. A laptop can pull 60-100 watts, which is a lot when you’re running on battery. Using a tablet instead of a laptop cuts that power requirement to 10 watts or less, and it can recharge off a USB outlet, which means you can skip the inverter — or recharge in the car while you’re driving.

In hot weather, bail out of the trailer by late morning when things warm up, and try to stay out as late as possible. This cuts down the length of time you’ll need the vent fans, saving about 24 watts per fan used. That power is put to better use after sunset when the temperatures start to drop.

Sometimes it’s easiest to relocate your power consumption to another place. In other words, if you’ve got to log some laptop time, consider relocating to a coffee shop and using their power (and wifi). Consider trying the campground showers to cut use of the power-hungry water pump in the trailer. Instead of running the inverter to watch a movie in the trailer, consider going into the local town to see what’s playing.

A lot of people hate conserving because it makes them feel deprived, but if you take a different perspective you may not mind so much. You may find that the steps you take to conserve open the door to opportunities for new experiences.

Battery Storage

Reader Jim L. wants to know:

“How is it best to handle batteries on the winter? Do I take them out? Store in my cold garage? Do I put a charge on them all winter to keep from freezing? Do I add water in the winter when they are not used? Do I store them on wood rather than concrete? HELP!! Before cold winter comes to Tennessee.”

Thanks for asking, Jim. It’s that time of year for many Airstreamers to think about winter storage. From your question, we’ll assume you don’t have an electrical outlet near where you keep your Airstream during the cold months.

In this case the best approach is to remove the batteries from the trailer and store them somewhere that you can keep them plugged into a device designed specifically to maintain batteries. We’re not talking about a typical battery charger here, but a dedicated battery maintainer. You can keep the batteries hooked up to a charge maintainer all winter without fear of overcharging. They are easily found in auto parts stores or online.

battery

You should add distilled water to the batteries anytime they need it (after first disconnecting the charge maintainer). The water will mix with the electrolyte in the batteries and won’t freeze as long as the battery is kept charged.

The stories you may have heard about storing batteries on wood instead of concrete are old myths based on batteries made in the olden days. You can read much more about winterization, batteries, and proper maintenance procedures in The (Nearly) Complete Guide To Airstream Maintenance.

battery-cover

 

Top 9 Airstream Accessories

You’ve got a new (or new to you) Airstream—what upgrades should be first on your list? Alumapalooza 7 attendees learned about these favorites from Rich Luhr, author of Airstream Life’s (Nearly) Complete Guide To Airstream Maintenance and Terry Halstead, an ASE certified master mechanic and Airstream factory-trained service tech.

“This is by no means a comprehensive list,” said Luhr. “There’s probably five hundred more things that we could add, and not everything on this list is for everyone. These are just a few great upgrades that you might want think about having, and see if they fit your lifestyle.”

1. A cordless drill

“…so you don’t have to kneel on your hands and knees in the mud to put your stabilizers up and down,” said Halstead. Use it with a Camco 57363 Leveling Scissor Jack Socket, available on Amazon for about $5.

“It’s a really great timesaver.” Luhr agrees. “Whatever brand of drill you choose for this purpose, make sure it’s 18-volt or stronger.”

2. In-line water pressure regulator

In-line water pressure regulator
In-line water pressure regulator

“Airstream trailers come with a built-in pressure regulator, but that does absolutely nothing for the hose,” said Halstead. “This goes on the spigot at the campground to give protection to your hose. I’ve personally been to a couple of campgrounds over the years that have had a horrible amount of pressure. So this little ten dollar device will save your $30 hose.”

[NOTE: If you have our Ultimate Water Hose you won’t need a regulator at all! The Ultimate Water Hose can take up to 360 psi without damage.]

The regulator prevents bursting by reducing what could be 120 psi on the spigot end to about 50 psi on the trailer end— and you won’t further reduce your water pressure inside. “Don’t forget to put this on your checklist so you don’t drive off and leave it at the campsite,” added Halstead.

Another pro tip from Luhr: “Put your water filter on the trailer end of the hose in case the hose itself might be a little bit contaminated.”

3. Range hood LED

Your newer Airstream came with a Baraldi, “the Italian sports car of range hoods,” said Halstead. “They look really great, and they work really great, but they do have one minor thing that could be upgraded”: the lights above the stove are halogen.

Range hood LED
Range hood LED

“Those do two things,” he said: “generate a lot of heat, and use a lot of power.” “Fifteen watts,” added Luhr. “That’s a fair amount for one light when you’re boondocking.” Simply pull out the bulb and replace it with an LED—problem solved. “That will cut your power consumption about 90% off those halogens,” said Halstead. “You can find them in various places online and at RV stores,” said Luhr. “Good LEDs aren’t cheap, and cheap LEDs aren’t worth it. They usually have a very short life. Ten to fifteen bucks is pretty reasonable for a good-quality LED of this type.”

4. Voltage monitor

“These are really simple, and they do a couple of things,” explained Luhr. “Just put it into any outlet in your Airstream when you’re plugged into shore power, and it will tell you the voltage that you’ve got available—which is super important. It’s quite possible that the electrical pedestal at your campsite has a wiring problem, and that can actually be hazardous to your health.”

Voltage Monitor
Voltage Monitor

There’s a reason we need to worry about the voltage coming into our trailers. “We know that it’s supposed to be 120 volts,” Luhr explained. “Rarely is it actually exactly 120 volts; there’s a tolerance. Your appliances are going to be fine plus or minus ten percent.” Drop much below that, though, and you’re at risk of burning out certain appliances—especially your air conditioner.

“Under-voltage is by far more problematic,” said Luhr. “Your air conditioner typically can go down to 105, but when you fire up your air conditioner that big compressor draws more power.” If your voltage meter shows 108 you might be okay, but keep an eye on it as it starts up; if the voltage suddenly drops down near 102 for more than a few seconds, “you’re going to very quickly burn out the motor in your air conditioner and you’ll be facing a big bill, either to fix it or replace the entire unit,” he said.

“You read online sometime, guys who say ‘it’s okay, I run my Airstream off a 15-amp outlet, I do it all the time.’ Well, you can get away with some things, but I don’t recommend playing Russian roulette with your air conditioner, with your plug, with your cord. Watching your voltage is very important, and it doesn’t matter if you’re in a brand-new campground—especially on hot humid days when everybody’s cranking. So this is an item you definitely should have.” On a summer day, leave the meter plugged in and periodically glance at the voltage readout to make sure it doesn’t get below a safe level. The AC compressor could be cycling on and off, and each time it will draw extra power.

5. A rivet tool

“A rivet tool is a surprisingly easy thing to learn how to use,” assures Luhr. “Basically you just stick a rivet in, hold it tight, pop the handle of the tool a few times, and the stem of the rivet breaks off when you’re done. It’s so simple. It’s easier than a screwdriver, honestly.” Halstead said, “That’s actually an advantage of owning an Airstream trailer. The rivets are extremely easy to install.”

Rivet tool
Rivet tool

Do you really need to travel with a rivet tool? Luhr says yes, and here’s why. “Someday there will be a corrosion problem where the aluminum and steel frame meet on your belly pan, and it will rot out around the rivets and fall down and drag on the highway,” he said. “If you don’t have a rivet tool, that’s a major problem. If you have a rivet tool and some aluminum pop rivets it’s only a five-minute problem that you can fix yourself, right there by the side of the road.”

A rivet tool is handy for replacing popped interior rivets as well, and can save you a lot of money. “Missing one or two inside rivets is not a serious problem; it’s actually perfectly normal,” said Luhr (“especially after traveling over rough road,” agreed Halstead). With your handy rivet kit you can solve the issue yourself, no trip to the service bay necessary.

“It’s a no-brainer,” said Luhr. “There are 5000 rivets in the average Airstream. You should probably be able to replace one of them.”

6. A tire changing kit

…is another item Luhr feels strongly about. “Your Airstream did not come with any tools to change a tire. This is baffling to me. They give you a spare tire, but no way to put it on.” Luhr believes that a AAA membership is not a good substitute for knowing how to change a flat.

“Everybody should know how to change their own tires, even if they don’t plan to do it,” he said. “You may be physically unable to, but if you have the knowledge and you have the tools with you, then at least somebody else can change the tire. The alternative is calling for roadside assistance, which might seem to be a great solution, but you’ll be sitting by the side of the road for hours, in a place you often do not want to be,” he said. “Waiting to have someone come to change a tire for you is like hiring somebody to dress you. If you could just do it yourself it would be so much easier.”

“It’s not hard to change a tire,” Luhr said, who offers a tire changing kit in the Airstream Life store. “I sell it because I believe people need it, but if you buy all these items yourself you’ll spend the same amount of money. Just buy the tools.”

The basics are a torque wrench (essential for correctly tightening the lug nuts when you put the wheel back on); a breaker bar (used for removing the wheel); an extension, and a socket.

The complete tire changing kit is also packed with a safety vest for roadside visibility, a pencil gauge to check the air pressure, and a six page instruction manual that explains exactly how to change a tire. “If you read that manual and take the kit out and try it, you’re going know how to do this simple job,” said Luhr. “Then you just throw the kit in the back your trailer and never think about it again until the day you need it.”

If you choose to buy all the parts separately, “make sure you don’t skimp on the torque wrench,” said Luhr. “Cheap torque wrenches are not worth the money.”

“Remember, the torque wrench is for tightening,” added Halstead. “It is meant to be used in one direction, and it will let you know when you’ve reached the proper torque setting, usually with an audible click. If you use it to loosen the lug nuts, you’re going to throw off the calibration and it won’t be accurate after that. Bad things happen when you don’t torque the lug nuts correctly.”

7. MegaHitch lock

“Storage facilities are not safe,” cautioned Luhr. “I hear reports almost every month from people who have lost their Airstreams out of supposedly secure RV storage that had 24-hour management living on site, with video cameras. Just last month some friends of mine found out that someone had broken into their stored trailer and the thousands of dollars worth of their tools inside were all gone. Management didn’t even know—and it turned out that the videocameras were fakes.”

MegaHitch Lock
MegaHitch Lock

Cheap hitch locks provide zero security. “You can see a video on my website where they take about ten different hitch locks and defeat them all anywhere from between five seconds and two minutes,” said Luhr. “If you spend about $40 or $50 on a lock I guarantee a thief could break into that it within thirty seconds.” Thieves can’t break a MegaHitch.

The $200 price tag “is a big expense,” Luhr admits. “And it’s heavy. But it works. If you’re keeping a $70,000 or $100,000 Airstream on a storage lot, $200 is not a lot of extra money. I strongly recommend it.” Halstead added, “Check with your insurance company. If you have proof that your trailer was locked with one of these, in most cases they’ll waive the deductible for theft.”

8. Tire pressure monitor

A flat tire can do lot more damage to your trailer than you might think. “It doesn’t just go flub flub flub and then you come to a stop,” said Luhr. “Often you have no idea that you’ve had a flat because it’s ‘way back there on the trailer as it starts to shred. It rips up your Airstream, destroys the wheel, creates a hazard on the road, and it leaves you with a thousand dollars of damage that could’ve been prevented.” While highly recommended, the TST tire pressure monitoring system is again, not cheap, but it’s the best. “There are many others out there that are frankly garbage,” said Luhr.

Damage from flat tire
Damage from flat tire

9. Portable solar panels

If you’ve noticed the items on this list have been increasing in price, you’re correct—and solar panels are definitely one of the most expensive Airstream upgrades. If you’re considering going solar but don’t want to make too great of an initial investment, portable panels are a good alternative.

Portable solar panels
Portable solar panels

“You can get anywhere from 40 to 200 watts; they fold up into a carrying case, they have their own charger, and they’re easy to use,” said Luhr. “Just plug them in, and they charge your batteries.” Luhr prefers the Go Power brand over Zamp. “They’re a little bit less expensive and the quality is excellent,” he said. “The 120 watt system comes with everything you need, and you can get a 7-way adapter that plugs right into your umbilical cable, no special wiring.”

If your trailer came with a factory-installed solar port that says “Use only Zamp”, the Go Power panels will plug directly in and work with it! Click here for more info on that.

What’s in a watt?

airstream light switchesWhen you turn on a light in your house, the light goes on. That’s simple. But when you turn on a light in your Airstream while on battery power, it may seem like you’re suddenly expected to have an advanced degree in electrical engineering.

That’s because managing power is one of the biggest challenges new owners face when they start roaming away from reliable campground electricity. Volts, amps, watts, and strange jargon quickly become part of daily conversation.

As Airstreamer said to me the other day: “I don’t know what any of it means, and yet I’m expected to know just to operate my trailer.”

Discussing electrical systems in an RV can be endlessly complicated, but let’s just keep it simple for now.

AC and DC—Your Airstream has two electrical systems, one for 120 volt AC power (just like the power in your house) and one for 12 volt DC power (from the battery).

Think of volts as a measure of pressure, like water pressure in a pipe. The higher the volts, the more pressure. North America uses 120 volts for ordinary outlets, and Europe uses 240 volts.

The 120 volt system in your Airstream is functional when the trailer or motorhome is plugged in. It powers the air conditioner, microwave, television, standard electrical outlets, and the refrigerator (when running in electric mode). It also goes to the power converter, which turns some of that 120 volt AC power into 12 volt DC power. This is used to recharge the battery.

When the Airstream isn’t plugged in, those circuits are off—in most cases. Why “most cases”? Because some Airstreams have generators which can produce 120 volts, and some Airstreams have inverters.

An inverter takes 12 volt power from the batteries and turns it into 120 volt power (the exact opposite of what the converter does). Because this will drain the batteries pretty quickly, inverters are usually wired only to a few things like TV and microwave, just so you can use them while you’re boondocking. You can’t run the air conditioner through an inverter because it draws too much power.

So how do we know much power something consumes? That’s where “amps” and “watts” come in. Every household appliance has a label printed on it somewhere that shows how much power it uses. For example, take a look at the power adapter for your laptop converter, or the charger for your tablet computer. In very fine print it will say something like this: “Input 100-240v~ 1.5A     50-60Hz Output 20v 4.25A max.”

That means this device can accept a range of voltage from 100 to 240 volts of alternating current (AC) at frequency of 50 to 60 Hertz. In other words, it can be used on both North American 120-volt and European 240-volt electricity. That’s nice to know in case we decide to use it in Europe, but we are really interested in the amount of that power it consumes.

This part tells us the rest: “~1.5A”. That means the laptop power adapter requires up to 1.5 amps. Let’s go back to the water pipe analogy. If 120 volts is the pressure, 1.5 amps is analogous to the diameter of the pipe. More amps means a bigger pipe, which of course can carry more water.

The total amount of energy consumed by this device is the product of the pressure and the diameter of the imaginary pipe. This device consumes 120 volts X 1.5 amps, which comes out to 180 watts. That’s the number we were looking for.

(By the way, if you’re wondering about the “Output” numbers, you can do the same math.  This adapter puts out 20 volt power for your laptop at a maximum of 4.25 amps, which is 85 watts.  The difference between 180 watts input and 85 watts output is lost mostly as heat.  That’s why the adapter gets warm when you’re using it.)

From light bulbs you know that a higher wattage bulb is usually brighter. That’s because it’s using more power. Watts tell us the total electrical consumption of anything, and we can use watts to compare different devices.

So why do we talk about 30-amp or 50-amp power cords? That’s the maximum your power cord is rated to carry on a continuous basis. A 30-amp power cord is really a 3,600 watt cord (120 volts X 30 amps) and we could refer to it that way but it’s standard to talk about it in terms of amps.

adapter

“Aha,” you’re thinking, “so a 50-amp power cord is really a 6,000 watt (120 X 50) cord?” No, because there’s a trick. 50-amp power in North America is supplied at 240 volts. So it’s really a 12,000 watt cord. I know, it’s not fair, but that’s the way it is. Now you know why the 50-amp cord is so much heavier: there’s a lot of copper in it to carry all that power. A smaller cord would melt!

That means an Airstream with a 50-amp connection has more than three times the power available to it compared to a 30-amp connection. Even if you’ve got dual air conditioners, you’ve got plenty of extra juice. Those air conditioners will pull up to about 4,800 watts at full tilt, leaving you with 7,200 watts for everything else. Our example laptop at a mere 180 watts is hardly even noticeable in the overall scheme of things.

Once in a while you may need to plug the Airstream into a regular household outlet, which generally provides just 15 amps at 120 volts (which is 1,800 watts). This is fine for keeping the Airstream charged and powering low-wattage AC appliances, like portable fans and laptop computers. But it’s a very bad idea to run the air conditioner on 15-amp power. It might seem to work, but long term it’s likely to damage the air conditioner’s compressor or cause overheating or even melting at the plug.

Now let’s look at the other power system in your Airstream. The 12 volt DC system is driven by the batteries, and it is responsible for powering everything else in the Airstream, including lights, water pump, furnace, “cigarette lighter” 12 volt outlets and USB outlets, fans, refrigerator (when running in gas mode), propane leak detector, stereo/DVD player, breakaway switch, etc.

By running most things on the 12 volt system, most power consuming appliances in the Airstream can be used anytime, which is convenient for roadside stops and overnights without hookups. Since the 12 volt battery is kept topped up by the 120 volt power converter, it will never run out of power as long as the trailer is plugged in. Only when the trailer is unplugged will appliances be working solely on battery power, and with a little conservation, battery power can last for days.

batteryYou might be wondering why we don’t have 120 volt batteries so that everything can use the same voltage. The reason is simple: 120 volt batteries would be extremely heavy and expensive. It’s much more practical to use a 12 volt battery, charger, and appliances—much like your car does. It’s also easier to design solar panels and generators that produce 12 volt power.

In the end, it doesn’t make much difference to most appliances. A light, whether running on 12 volts or 120 volts, will produce about the same amount of illumination for a given wattage. In other words, a 12 volt light that consumes 1 amp is about the same as a 120 volt light that consumes 0.1 amp. Both consume a total of 12 watts and both will be about the same brightness.

So a watt is a watt, whether that power is supplied at 120 volts, 240 volts or 12 volts. If you ever get confused about comparing power from your solar panels, generator, or the needs of various appliances, figure the watts (remember, volts X amps = watts) and you’ll have a fair comparison.

Rich Luhr is the author of Airstream Life’s (Nearly) Complete Guide to Airstream Maintenance,  available at the Airstream Life Store. There’s a lot more about Airstream electrical systems, including maintenance tips, in this 220-page book.