Desert power (without lots of generators)

Desert power (without lots of generators)

Updates: LED lights, inverters and chargers are all much cheaper today. Use only LED light, no CFL or incandescent. This article was written in the 2000s and needs some updating.

You're way off the grid, but you want electricity. A number of camps set up a camp generator system. Center camp has a power grid built by the DPW. Most rental RVs come with a generator. But how much do you have to use it?

If you're going to have a big light show, or a radio station, or lots of amplified sound, then a generator is what you need, at least while you're doing those things. It's also about the only thing that will run a traditional air conditioner.

But can you get by without one, or running one minimally? It can be done, and not just in the Alternative Energy Zone camp (lots of great resources on their page), which is generator-free. Let's face it, generators are noisy, and they generate bad smells, and they use fuel and pollute the air. It would be nice to reduce them. At the end of this article, like Paul Atriedes, you will understand desert power.

If, on the other hand, you are in a big camp with big power needs, you may want to learn about the opposite end of the spectrum -- making a playa power grid.

(This article is for folks who go to Burning Man.)

Lighting

Of course, for lighting, many camps use fuel-based camping lanterns. You can get 16oz cylinders for them cheap at Costco, and many people bring a pipe that hooks them up to a larger propane cylinder, the same one powering your cooking gear. A full propane cylinder will run these lights for quite some time.

For electric lights, you will be amazed at how much less power LEDs take compared to incandescent lights. To my amazement, most RVs use wasteful 12v incandescent lights, and those can drain your RV battery pretty quickly. There are now LED replacements available for the standard car lights used in RVs and they can cut your power use. Get them.

Use LEDs at all times. They are more efficient than flourescent, and don't emit murcury when they break -- an they also don't break.

You can get LED lights for 12v lamps in RVs, and 115v LED lights if you use inverters, and nice bright LED flashlights and lanterns. The 115v lights are now found almost everywhere.

LEDs work well in flashlights because they focus their light tightly. That makes you appear to get more light for your power -- and they never break and rarely burn out.

Decorative Lighting

Of course el-wire, that glowing wire, takes almost no power, so it's a great decorative lighting tool. 12v drivers are cheap and plentiful and even a small battery pack will run them for a very long time.

Also consider LED based decorative lighting. LED rope light is more expensive than incandescent but it doesn't get hot and uses vastly less power. They also last much longer. You can get cheaper non-LED 12v rope light which is still better than running off inverter. One advantage of 115v LED rope lights and christmas lights is you can daisy chain lots of strings due to the low current.

Check out Forever Bright Christmas lights, which can be found in many stores at Christmas time. Here is an online store that sells them. They can also be had sometimes on eBay and other online stores. For example, their string of 100 lights is just 3.6 watts total. You can run that for a long, long time.

Battery power

You'll need battery power. Go to Costco or Walmart and get some of their Marine/RV deep cycle batteries. Only deep cycle batteries, which are meant to be drained deep, are a good idea for desert power. Strictly speaking, the Marine and Hybrid batteries, which can also start an engine are not as good as the dedicated deep cycles sold for wheelchairs and solar power systems. But they are cheaper and more readily available. But if you find good deep-cycles at a decent price, buy them, especially if you have other deep cycle uses.

The number to look at on a deep-cycle battery is its amp-hours. (Multiply by the voltage, typically 12v, to get the watt-hours, which is how much energy the battery stores.) If it doesn't list the amp-hours and say "deep cycle," it is probably not the battery for you. An amp-hour is the ability to deliver an amp for an hour. On a 12v battery, an amp means 12 watts. To run a 36 watt light for an hour requires 36 watt-hours, or 3 amp-hours from a 12v battery. Short electricity course: Watts = Amps times Volts. Watt-Hour = 1 watt for an hour.

Costco's 85 amp-hour battery for $44 is your best buy. The 115 a-h for $60 is also good. Of course it's very heavy. You will want a battery box or other plastic box to hold it while you travel, and secure it well so it doesn't tip. (Auto parts stores have these.)

(You can also check industrial battery supply houses for refurb batteries at even lower prices.)

Just one of these 115ah batteries, fresh and charged up, holds about 1.3 kilowatt-hours of power. In other words, it can run that 38 watt fluorescent for almost 30 hours, which may be all you need. It will run small amounts of the el-wire or LED lights the whole event.

You can buy 2 or more batteries, and then stop by an auto parts store to get 4 gauge battery cables to join them. only link them when they are all fully charged or fully discharged! Don't link a charged battery to a discharged one unless you know what you're doing. Don't link different types or ages of batteries -- the stronger battery will try to charge the weaker one (especially if it has shorted or bad cells) and the whole system will drain out much more quickly than you expect. This means that replacing one battery in a pair often leads to just ruining the good one.

When you are done, you will have a nice power backup kit for your house in the event of a long blackout, too.

You may want to consider sealed batteries (SLA or AGM) which, as noted, are sealed and you can tip them without spilling, even install them sideways. That's a lot safer if you expect to be moving your batteries around a lot without mounting them (as in a car.) These are a fair bit more expensive, and tend to be sold in smaller sizes.

You will find SLA batteries in those little "portable power kits" with a handle and 12v jack. Very convenient, but typically only 15 to 20 amp-hours for as much as the 88 amp-hour non-sealed.

If you plan heavy drain -- 150 watts or more for long periods -- a single battery will not last as long as the amp-hours written on the outside. Consider having a bank of 2 or 3 batteries. Your stereo may say 200 watts but it probably isn't drawing that much at normal volume levels.

Here is a good page on 12 volt battery use.

A note on wiring: Your wires can only carry 10% of the power they do when using them for 110v, because the current is 10 times higher for the same power. Current is what matters. Be sure to use thick wire in any 12v circuits. (That's why jumper cables are such thick wire.)

Lithium Batteries

If you want to have a lot of watt-hours at a low price, lead acid is your likely choice, but today Lithium batteries have gotten a lot cheaper. They are much ligher and spill no acid. But they will cost you perhaps $300 or more for a kwh compared to $75 for deep cycle lead acid. They need alternate chargers, you can't charge them with lead acid chargers.

Your car battery

Your car battery is designed only for starting and lights. If you drain it deeply, you will shorten its life a lot. It probably has 30 to 50 amp-hours (2.5 minutes of "reserve capcity" is similar to an amp-hour on your car battery.) However, you can use it for minor stuff and it won't be the end of the world. I wouldn't drain it a lot with high power stuff. And you can run your car to recharge it, or if you have to do something high-power (like run a power tool on an inverter) you could start the car to do this.

If you want to do this seriously, you could swap your car battery for a "hybrid/marine" battery. If you do drain your battery, getting a boost at Burning Man is usually pretty easy, especially if you have your own jumper cables.

The car battery approach is a lot cheaper, and OK for spot power, running your computer or battery charger, but it's not a great solution for powering a camp.

Charging

You will want a charger. You need to charge the batteries before you go, and immediately after you get back. (If you leave a lead-acid battery below full charge for a long time, it will go bad on you.) You also may well be able to recharge them on-playa.

Chargers in the 15a range are fairly cheap and can be found at many stores. I just bought the Vector Smart Charger which is about the best price for one that can do 40 amps. They have a 35 amp model for $75 which is probably a better buy because you only get the full 40 amps into a big battery which is mostly empty. (These are affiliate links, but you can also hunt for the product elsewhere.) These products now have the Black & Decker name on them.

Your charger can recharge in the desert. If you have a generator, you probably will run it some of the time (to do air conditioning in the hottest part of the day in an RV, for example.) During that time you should recharge batteries, and the more current you can get, the more effective it will be. This is definitely true if you are running the generator just to charge your batteries.

If you don't have your own generator, chances are your neighbour will. I've never seen anybody who wouldn't let you plug a charger into their generator while running. (One possibly upside of the older, "semi-dumb" automatic chargers is that they can be left on and connected. Whenever the generator fires up, they will start recharging. Computer-based chargers need to be turned on independently.) Consider bringing a small dolly to make it easier to move your heavy battery pack over to your neighbour's power source.

Your charger will be handy outside Burning Man, of course, for maintaining other batteries, jumpstarting cars etc.

It's wasteful to run the generator just to top-off the batteries, ie. if the charger is down to putting only 5 amps or so into the battery. (Your charger will probably have a meter that shows the charging current.) Your battery can handle not being topped off during the week in BRC.

My old camp, the Embassy, runs with a giant cart with over 1000 amp-hours of batteries on it. For a few hours each day, a much more industrial charger is connected to the cart while a generator runs. Then there is quiet, smell-free power all night long. The wireless internet network at Burning Man runs partly off this, if you have used it.

Many generators also have a 12v charging output, usually at 8 to 12 amps. That may not be as good as the fancier charger above. Note that many RVs, when you run the generator, recharge the RV battery but also at this slower rate. (On the other hand, the truck engine in the RV usually charges the battery at a much higher rate, up to 80 amps while driving.)

Yes, if you don't want to buy a charger, you can charge your deep cycle battery from your car using jumper cables. Start the car soon after connecting (or you will drain your car starter battery) and be ready for a spark when you connect the final black clamp to your car chassis. You will get 30 to 40 amps from your car at idle. Wear eye protection and don't be naked. Have your battery in its box. It's not the ideal way to charge, and not a good way to top up, but if you have no other choice you can do this.

Inverters

If you have 110 volt gear, you need an inverter. In the last few years these have gotten super cheap. You can find them anywhere. Fancier ones will have fans and a lot of power. A 400 watt inverter, which will handle most things you are likely to power (though not power tools or a microwave) can be had for $25 at costco these days. You can even get, for not that much money, inverters at 700 watts, 1000 watts or even 3000 watts. These could even run your microwave oven -- but not for long.

Inverters are not perfect. They waste about 5 watts even when not powering anything, and add about 5% to the wattage of devices you run on them, so turn them off or disconnect when not in use.

(If you buy an ammeter to measure current, check to see if your inverter still draws power when its switch is off.)

Power Factor & the Kill-a-Watt

For many of the inverters out there, you may have to learn about "Power Factor." With AC power, some things you plug in use the power in an out of phase way that bothers some inverters and generators. They look like they are using a lot more power than they are, which can cause the inverter to refuse to operate. The main culprits are electric motors, like those found in air conditioners, but many of today's fluorescent lights -- the efficient lights I told you to use -- will have a bad (low) power factor, and your inverter may not run them.

The answer is to test things in advance, and possibly look for an inverter that will do the job. You can measure the power factor (as well as many other things) for your loads by getting a cheap "Kill a Watt" unit. These units are found in the big hardware stores and are a great thing to have when both planning your burning man power and using it. They will tell you how many watts your devices are learning, the power factor, the quality of your power and much more. The big thing you can do is plug in your stuff and run it for a while to find out not just how many watts it uses at any given moment, but the kwh over the long haul. That will let you figure out how much AC power you must deliver.

12v devices

A lot of 12v devices are out there to run right off your batteries. Blenders (This site has all sorts of other stuff, too). Battery chargers for your cameras and other devices. (Yours might not but a number can be found.) Computer power supplies that run of 12v (for car or airplane) are handy enough you may wish to get one, it's more efficient than using an inverter to power your 110v power supply.

You can buy 12v cigarette-lighter sockets, multi-way splitters etc. at Radio Shack, Fry's and other stores.

You can also get fairly cheap converters that convert 12vdc to other common DC volatages to power your other electronic devices that need 6v, 9v etc. These will be much better than using an inverter.

More and more stuff out there is ready to run on 12v, which is great for you. However, using 12v power for heat (coffee makers, electric blankets, oven) or refrigeration is just plain silly. Find regular fuel-powered devices for heating and cooking. Electric is not greener on the playa.

Solar

It's not worth it to buy solar just for Burning Man. It's not even green.

The best price for solar panels is on eBay. You will want a charge controller too, those are under $30.

Still, a 42 watt panel like I got for $150 (a very good price) still only delivers about 300 watt-hours in a day of Black Rock sun, something the 35 amp charger can do in under an hour (into a discharged battery.)

Solar stuff bought just for burning man or camping is "false green" because it takes a year of output from solar panels to build them. Solar panels are only green when used full-time, with grid-tie.

However, no question that if you already have solar, Black Rock is a great place to use it. Just make sure to tilt it to match the angle of the sun (40 degrees from horizontal, pointing south,) that makes a remarkable difference.

If you are using solar, to be green you must put the panels back into an always-used grid-tie solar installation when done, and probably took them from there. Do not buy solar just for camping unless you want to crap on the planet.

Cooling

OK, a 1500 watt air conditioner needs the generator. But you might want to look into getting an evaporative cooler, known as a "swamp cooler." These will cool in an open space with just 100 watts (and possibly much less,) and so can readily run on batteries. They work better the hotter the air and the lower the humidity. In other words, there are few places they work better than the Black Rock Desert. They do use water, but just a few gallons to run in the hottest hours per day. They cool people, not rooms, so are good for shade structure or tent, or RV with windows open.

Swamp coolers can be found at most home appliance stores, and cheap at Costco. Swampy sells them as well as 12 volt coolers but the 12v ones are meant for cars and so not as efficient as you would hope for a tent. However, they have a new 12v model, which, while not cheap at $267 seems extremely low power -- you could run it all week on one battery.

You can also look into misting fans, which act doubly by putting some fine mist on you to cool you directly.

For refrigeration, most people rely on the fridge in an RV in their camp. Those run on propane. A real fridge could be run but needs a pack with serious batteries. Those 12v fridges they sell are a waste of time, they take too much current and ice from Arctica does a much better job.

Of course, a cooler full of ice, with a backup freezer full of dry ice, can easily last you 5 days if you handle it well. Then go to CampArctica for more ice.

Dry ice can be found now in a lot of places, even some gas stations and surprisingly my local Lucky's. Dry ice gives you a super-cold freezer, not a fridge. You can use dry ice to keep your ice for your cooler if you don't want to go to CampArctica's line too often.

Heating

Yes, sometimes it gets very cold in the desert. People run their RV furnaces but the fans in those will drain the battery fast. That's OK if you are getting a regular generator recharge as described above. Bring a warm sleeping bag or consider a catalytic camping heater, which can be run indoors and can survive without a fan.

When you need the generator

If you have your generator, aside from charging batteries and running the A/C, you may find it's worth using it to do short jobs, like a few minutes of microwave cooking, or running your power tools for an hour while constructing your camp or art. Short bursts won't be nearly so annoying to neighbours as hours and hours of smelly exhaust. But with today's inverters being so cheap, you may find you can run even these big devices off your battery pack.

If you're buying a generator you may want to do it locally. On the web This site has a really good variety to help you choose even if buying locally or elsewhere with Froogle.

Today's best (though higher priced) generators are "inverter generators." They are much quieter, and produce cleaner power you can trust your more delicate gear to. But they cost a lot more. You may be tempted by the cheap 5,000 watt generators you find in stores. These are good for job sites to run power tools, but not really suitable for a lot of your uses, and they are loud. Very loud. You will hate yourself. Your neighbours will hate you. They will attempt to sabotage your generator. Don't be tempted by that price. You can try to build baffles, and surround the generator with cars, but that will be more time and cost than just getting the inverter generator. And it probably won't work. Get either an inverter generator or a generator specifically designed for quiet operation.

Giant generator

If you have a very large camp and a serious need for power, such that you know you will end up with many small generators (RV and otherwise) in your camp, consider going the other way to renting a larger diesel generator and sharing it. You can rent these for about $500/week at many rental places, though you also need power distribution cables, etc.

Large generators are much, much better than a collection of small ones. They are way more efficient, and burn less fuel, make less noise and emit less pollution per kw than small gasoline generators. The main downside is a shared generator will be on for long periods -- you don't do the efficient thing of just firing it up when you need it.

Note that large generators are not better than small ones if you run them all the time at idle when there is no power demand. The larger the generator, the higher the idle fuel use will be, even if nobody is drawing power. So don't get more generator than you need.

Note as well that usual generators and temporary power systems do not have the special TT-30 plugs that RVs use to plug in. You will need to build your own RV power stations, or plug in the RVs to 20 amp regular plugs, which in some RVs means you might surge when the AC starts, and you can't do AC and microwave. (I think you'll be able to handle that.)

Make sure you make a very good connection, and don't use those cheap 14AWG or thinner extension cords to plug in an RV -- in the heat of the desert, you really can melt the plugs and adapters, I have seen it.

I have a special article with far more details about running a big shared generator.

Other things to bring:

Extension cords, both 110 volt and 12-volt. (The latter can be found at automotive stores, Radio Shack, etc.)

A very long (100' or more) outdoor extension cord to borrow power from neighbours who are running generators. This should be heavy duty (12AWG, sometimes marked as 12/3) if you are going to run any real loads over it.

110v power strips or splitters so you can plug in many things, or if you take power from a neighbour, don't take away their only plug.

A voltmeter, to check your batteries.

A timer, to turn stuff off. I have one that uses a photocell to turn lights on at dusk. But if you can, come around later and unplug your inverters as they do take some power, about 100 watt-hours/day. Beware some inverters draw power even when their switch is off.

Spare fuses for inverters, power supplies. Spare car fuses. You don't want to blow a fuse and not have a spare in BRC!

Basic Kits

12v kit:

  1. Costco 85 amp-hour battery ($48)
  2. Battery box or other box (auto parts store, $10)
  3. 12v "cigarette lighter" socket with clamps (~$6.49 at Radio Shack)
  4. Cigarette lighter socket 3-way plug (~$10 at Radio Shack)
  5. 12v gear. (LED lanterns, battery chargers, computer power, blender, etc.)
  6. Elwire driver and elwire
  7. Borrow a charger to charge, or get a charger, even a cheap slow one, and bring it.
  8. Optional: Computer adapter, DC-DC converter to power small devices.

If you know somebody nearby will be running a generator, haul your battery and charger to them when you see them do it.

110v kit

  1. The gear above.
  2. 400 watt inverter ($25 at Costco, and many other stores)
  3. LED lights from Costco or home depot (or the web.)
  4. Your 110v gear, and heavy duty extension cords and 3-way plugs

Test it before you go! Don't learn you don't have the right gear only after you get to that thing in the desert.