Burning Man Pages by Brad Templeton


My Home Page


Brad Ideas
(My Blog)


Burning Photos

2010

2009

2008

2007

2006

2005

2004
Aerial

2003

2002

2001

2000

1999

1998

Burning Panos

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

98-99

Burning Articles

Pano / General Intro

Burning Blog

What is BM?

Desert Power

Free Phone Booth
On-Playa
Making of
Instructions
Maps Voicemails

Star Map

Save the Man

The Irreducible

Thoughts

T-Shirts


My Subsites

Photo Pages

Panoramic Photos

RHF Joke Site

Spam

DNS

Charles Templeton Home

Ty Templeton Home

   
 

Burning Man Power Grids with Big Generators

Burning Man Power Grids with Big Generators

It's possible, even easy, to meet most of your power needs at Burning Man with low power devices and batteries. See my page on Desert Power to learn about that.

However, if you want to run high power things, like power tools, air conditioners and big lighting and sound, you may need a generator. Generators can be noisy, and smelly, and they're not very green. They're getting better, and quality RVs have pretty good generators, but they still have many faults.

Running a generator just to charge batteries with a low-current charger can be very wasteful. Such chargers don't draw much power, but the generator can only idle so low.

Portable Generators

The portable generators found in hardware stores are the wost of all. Loud, smelly and their power isn't very good. Your neighbours will hate you, beg you to turn it off. You also would not want to run things like a desktop computer or unprotected electronics on them. They are mostly for power tools. A newer generation of "inverter" based generators provide cleaner power. They tend to be a bit lower powered, but quieter. You can use them for spot power. The cheap generators may do 5,000 dirty watts for just $600, while the inverters will cost $800 for a

RV Generators

If you have RVs, you probably have generators. Most RVs have plugs on the outside that can be used to tap about 15a of power from the RV generator to run tools etc. You can run another RV's ordinary power needs from another RV, but should not run the other RV's AC, and probably not even the microwave. Some rental companies charge an hourly fee for generator use, and they all will burn 1/6 to 1/2 a gallon of gasoline per hour even when idle, much more when running the AC.

Still, you are already bringing the RV generator, and it's a quality one, so it may suit your needs.

Power Grid

Important note: This is ad-hoc advice on how power grids have been built at Burning Man. The advice here may or may not be in compliance with appropriate electrical codes. If you build a power grid, you want to have a skilled electrician oversee your project. This is serious stuff that can cause fires or death.

More advanced camps build a power grid with a high power diesel or biodiesel generator ranging from 25kw and up. If you build such a grid, you will place the generator somewhere its noise and smells will not bother anybody, and you won't allow any other generators to run in camp (with some special exceptions.)

A grid can be a good idea because the bigger the generator is, the more efficient it is, provided there is a modest load. Small generators are not very efficient at all, and burn more fuel for the same power. Large generators, however, idle at a higher fuel burn rate, so should only be used if you have real power needs 24/7. (Or they can be turned off when not needed.)

(It's not really a grid, of course, with multiple power sources, but we call it that to compare to the big power grid we're used to at home.)

You can rent such generators from a variety of companies. Several major vendors such as Cashman in Reno and Kohler in Las Vegas even do delivery and pickup from the Playa, though it's not cheap. Otherwise they come with a trailer that you can use to tow them to and from the playa. Diesel and Biodiesel delivery can be arranged on the playa. Your generator needs a fuel tank that will last it at least 1.5 days, as fuel delivery times are somewhat random.

Rental Terms

Typical generator rental companies will price a "week" as equal to 40 hours. (Because they don't open on weekends, however, they will often view pickup Monday and return day after Labour day as a week, or even pickup Friday and return Tuesday after Labour day as a week. Especially if you ask nicely.

But 40 hours is not a lot. If you want 24/7 they will 1.5x or double the price. You probably only need spot power on setup days, and only need to turn on 24/7 on Monday morning and shut it down the next Monday morning while striking camp. If you need it to power setup/teardown tools it will be longer. You may find you can get by with a daytime-only phase, and shut it down from 2am to 8am (when air conditioning need will strike up.) Don't forget you almost surely have other generators for small off-peak needs. (If you plan to run electric fridges/freezers, you probably need 24/7.)

So work out your hours and make sure you negotiate the hours of use as well as the time with your rental company. They care more about hours as long as they have inventory. You may also find the monthly rate (usually including 160 to 200 hours) is a better deal. Bigger generators will not cost that much more than smaller ones, so if you can share with others it is a great idea -- but bigger generators do run a bit more fuel at idle. They are more efficient at higher loads.

3-Phase and "single" phase

Big generators can be run in two modes. One is called "single phase" and is similar to household power, meaning it actually has two phases, 180 degrees apart. This delivers 120v to neutral or 240v between the two phases. (If what I just wrote confused you, you may not be the right person to set up a power grid for your camp.)

Rarely on playa do people need 240v. RVs do not use 240v even though their plugs remind you of dryer plugs.

The other mode is 3-phase. With 3-phase power there are 3 "hot" lines and a neutral, as well as ground. The 3 hot lines are 120 degrees apart. Each will give you 120v to neutral, and any two will give you 208 volts. (Some high power equipment will run on 208 as well as 240v as well, but again, generally you never use this format.)

The big advantage of three-phase power is that most of these generators only put out 2/3 of their maximum power in single-phase mode! If you want all the power you're paying for, 3-phase is the way to go.

Your generator will also have a variety of power sockets on it. Some of these may be Hubbell "twist-lock" 50 amp sockets, which I will refer to as "tempower" sockets, because they are commonly used in the power distribution systems of contractors. These sockets often only provide juice in single phase mode -- they are disconnected in 3-phase mode -- so if you want to plug tempower equipment into them you may need to run single phase, even though it gives you less of the total power of your generator.

Power distribution

The hard part of your power grid is distribution. You really want to avoid running the power over long distances. To do so requires very thick, expensive wire. To not have such wire involves both the problem of voltage drop, where the voltage at the remote end gets so low that equipment gets bothered, and also the issue overheating the wire when combined with the heat of the playa.

You can use a Voltage Drop Calculator to figure out what the voltage drop will be at your maxiumum load on your wire. Code suggests keeping it below 3%, but in reality most equipment can handle more. Going really low could bother some equipment, and also means your wire is probably getting too hot.

There are all sorts of connectors used in power distribution. Some are standardized by NEMA, here is a chart of what many of them look like.

Standard "Edison" plugs

Your generator will have some standard household sockets, known officially as an 5-15 and often called "Edison" plugs/receptacles. The ones on the generator may have one of the pins look like a "T" because they are rated for 20A, instead of the 15A common for households. This is the 5-20R. You can plug regular 15A cords into them but must be careful not to put 20A loads on them if you do.

(If you do a fancier power grid, your distribution points will also have these receptacles so all this applies there too.)

If you plan to plug in high power devices, especially RVs, you need thick extension cord. Those 16AWG orange outdoor extension cords you often see won't cut it. Wire thickness is known as the gauge, and in the USA, it is measured on the AWG (American Wire Gauge) system.

If you want to run a full 20 amps, 12AWG wire is recommended on runs of 50' or less and 10AWG on longer. These extension cords are more expensive and can be found at Costco and Home Depot. They are sometimes called 12/3, meaning 12AWG and 3 conductors (live, neutral and ground.) 10AWG is even better, and good for up to 30 amps for 50' -- it's what you want for plugging in an RV over more than a short distance, and it's what the RV's own power cable is made from. You don't want to plug in an AC over 14AWG or smaller. (Higher AWG numbers are smaller wire.)

RV Plugs

RV plugs are their own special animal. Known as a "TT-30" they handle 30 amps, but use only one phase (ie. they have a hot and a neutral just like ordinary edison plugs) at 120v. It's rare to find rental equipment with the TT-30 socket on it. You will probably have to build it. Most RVs have a 25' power cord that comes from somewhere on the driver's side, usually the rear but not always. (Since you may not know what rental RV you will get until rental day, be prepared to reposition RVs or have extensions.)

RVs will come with an adapter to let you plug the TT-30 into an Edison receptacle. That's OK up to 20 amps, but use a 10AWG extension cord for this if you have to go a long distance, 50' of 12AWG is also OK. You will probably find you can't run the AC and microwave at the same time, but that's not a big problem for many folks. Make sure the adapter is in good shape and well seated because thin edison blades have been known to get very hot, and even melt in these adapters if current stays around 20a.

You can also buy RV extension cords which are 10AWG and have TT-30 plugs. These can be found at most RV supply stores, and online. Alas, most RV rental companies don't rent them, though we should encourage them to. Try Camping World or sometimes eBay.

Big RVs with two ACs have a special 50 amp plug. These are rare and probably not worth supporting in your grid. They do it using two phases, and even have adapters to let them plug into two TT-30s at once. They do not try to get 240v. If they must plug into just one TT-30 it means they can only run one of their two ACs. They will whine but unless they want to kick in lots of money, say no.

For plugging in RVs, you can go two ways. One way is to build distribution panels with TT-30 sockets in them. Another is to build special splitter cables that have an L21-30-P plug on one end, and split it out to 3 TT-30 receptacles. The L21-30 is a 3-phase, 30 amp twist-lock connector that is commonly found on power distribution boxes and on some generators. More details on this are below. (You can make special cables from other plugs with 2 or 3 phases in them to power groups of RVs, too.)

Tempower/Spiderbox/Lunchbox/Gangbox

Generators are often rented to construction contractors who refer to the equipment as "tempower" or temporary power. For this, they start with the 50A Hubbell CS6364/65 connector, which gives you 2 hots with 50A each, for a total of over 10KW. You can readily rent 6AWG 50' and 100' "tempower" cables with these plugs on them, and you can also readily rent distribution boxes known as "spiderboxes" which will pass through the tempower cable and provide a variety of 20A Edison sockets. (They also often provide a 240V twist-lock plug but this has no neutral so will only get you 208v on a 3 phase system or 240v on a single phase system -- never 120. Some people have modified spiderboxes they own to add other types of sockets including ones with neutrals more suitable for getting 30A power to RVs.)

You can run Tempower boxes/spiderboxes off 3-phase if you wire up a tempower receptacle to take 2 of the phases, just remember you can't get 240V. This won't help you plug in RVs for full 30a power, though. And you may be wise to decide that 20A is enough for all but the biggest RVs.

Camlocks (Camlok)

For very high current, power is no longer run in bundled cables with a neutral, hot and ground in the same sheath. It's better to run it with individual conductors. Your generator may come with 1 or more sets of female camlok sockets for the 5 individual wires of 3-phase -- 3 hots (black-red-blue,) one neutral (white) and one ground (green.) The most common camlok style is series 16, and this is often just referred to as a "cam" or "camlock."

Chances are if you're doing a big grid, your main power bus will consist of thick wires plugged in with camloks.

(At 2AWG and thinner, you can often get cables with 5 wires together in "banded" form, which is to say loosely bound with bands to make it easier to handle.)

Your generator may also come simply with bare lugs, and your rental company can provide pigtails to let you attach camlok females to them. Working on the raw power bus is dangerous, and should be left to a licenced electrician or other qualified party under the NEC. This is stuff that can kill you or others.

You can plug in very thick wire into these, including wire known as AWG 4/0 (4-ought) which can handle as much as 400 amps. 4/0 wire is very heavy -- a 100' single conductor will be about 90lbs. You need it for long wire runs or heavy current. So running 100', which requires 4 of the 4/0 wires and a ground wire will weigh over 400lbs. You will easily be hauling 1000lbs or more of gear to the playa.

Your single conductor wires will provide your main power tree. You can split them using camlok distro boxes, or often just with "Y" splitters (known as two-fers and three-fers) which have one male and 2 or 3 females, and eventually reach distribution boxes ("distros") which will allow you to split to smaller, lower current wires and receptacles, and which will have circuit breakers to protect those wires and things connected to them. In general, you should not plug a thin wire directly into a source that can provide more current than the wire can handle. Be wary of "snakebite" adapters that will do this unless you will be feeding directly into a breaker. If your wire shorted, it could melt, and start a fire if it's near something.

You will be able to rent a variety of distros that plug into camloks at up to 600A per phase. You may also find "minicams" (known as series 15 camlok) which can handle up to 100A and generally are used with 1/0 to 2AWG wire. Providers rent distros with Edison plugs, of course, but also with tempower sockets, and the L21-30R or L14-30R 3-phase receptacle described above which allows you to build a Triple-RV cable.

Here for example is Kohler's catalog of distribution boxes though you will see similar things from other high-end suppliers.

Bates/Stage Pin

Another distribution system, commonly used in stage lighting, is the "bates" connector. Bates plugs are huge 3-prong, 120v plugs that run all the way up to 100A. They are an older system, without twist-locks or weather protection, and not quite as safe, but still allowed. The plus is they are simple and cheaper to rent. You can get distros that will plug into your camlok wires (even doing pass-through) and will have female bates receptacles on them. You can easily rent bates extension cables, including 4AWG ones which can handle 100 amps. (That's the same amount of power as the tempower cables which use two 6AWG wires at 50A each.)

Bates distros with Edison sockets (or smaller bates plugs) are common, and readily available from houses that do stage and concert lighting. They are often called lunchboxes or gangboxes. You can also build RV distribution panels that have a bates plug (or a tempower plug) and have TT-30 RV receptacles on them.

Placing your power grid

Ideally you want to keep your wire runs as short as possible, and as thick as possible for most of their length. You also want them to be similar in length if you can. People who are farthest from the generator (where distance is a measure of both actual feet of wire and how thick it is) will see a slightly lower voltage than those who are close. In addition, people on legs with high load will see a lower voltage. You can sometimes bump the voltage at the generator up a bit to improve the voltage at the far ends, but this runs the risk of giving too much voltage to any people who plug in very close, or right on the generator.

The large generators are much quieter per kw than small ones, and you can also get "movie quiet" generators which cost extra but are remarkably silent. You would not be bothered camping 20' away from them. Sometimes you will get one for no extra charge, and sometimes you order one and don't get it, so be prepared.

In any event, plan so that chill spaces and people's tents are not that close to the generator. Use the space around it for parking, or the showers, or whatever. However, you will need to have road access to the generator for the refueling truck throughout the event.

Most generators will have some Edison plugs on them, and you may decide to have some campers plug into those if you are not doing voltage tweaking. (If you do, tape them off with a warning.)

If you are doing a tempower style grid, you will have rented some 50A tempower cables in 100' and 50' lengths. You can put 5 or (maybe) 6 RVs on such a line, but if you do, try to keep it to 150' -- 200' at the most. If your camp is large, this may mean the right plan is to put the generator somewhere near the middle (with a road to it) and fan out the cables.

If you are going to use camloks and 4/0 wire, you can go quite a distance. In 2007 we built a 7-camp power grid that had users over 700' from the generator. Mind you, the wire to do this was quite expensive -- but cheaper than getting generators for every camp. Your generator may have one or two rows of 5 female camloks. You might wish to send out a power bus in 2 or more directions, and have sub-distribution points where you can then run tempower, or Bates, or RV breakout cables from appropriate sockets.

For your power bus you need 4 thick (2/0 to 4/0 depending on length) wires, but the ground wire can be thinner, as thin as 6AWG -- this will save you cost and and most particularly weight if you are hauling it about.

If your runs are shorter, you can use thinner banded cables available from rental outfits. These tie together 4 or 5 wires of 2AWG or 1AWG and are suitable for about 140A per phase for short runs of a couple hundred feet at most. Because the desert is hot, get wire with high-temperature insulation.

You can run your wire right on the ground, but should take steps to assure people don't kick it or park wheels on top of it. You may also elect to trench it if you can get access to a trencher. If you trench it, which is a must going under city streets, be sure it's well marked so nobody decides to drive rebar into the ground where it is. The results could be shocking. People will be idiots out there. Trenching will keep the wire cooler, which means it can handle more.

Arranging RVs and other users.

Since RV power cords are shorter than the RVs themselves, they need to park with care to assure all their power cords can reach your RV distribution points. It will be hard to just line them up on your border as people often do. "T" configurations and "U" configurations may make more sense for a cluster of 4-5 RVs. Consider RV extension cords, or accept that some of the RVs in a cluster will have to run on 20A with 10AWG or 12AWG extension cords. (This is usually tolerable for smaller RVs.)

You need to pay attention to this on the map. You don't want to put a lot of work into a fancy grid and find people can't plug in and insist on not paying, or running their noisy, smelly generator.

Most importantly leave some slop. People will not camp exactly where you tell them, and wires will not always go in straight lines. In fact, many a camp barely resembles the map by the time people get there.

Sizing

To size your generator, count your RVs or other units with air conditioning. Allocate about 2KW per RV. They can actually draw 3KW but they won't all do this at once. You will only use this on a very hot day, and your night needs won't even touch the daytime peak. Also include allocation for other high power devices (welders and other power tools, fridges, freezers etc.) which will also want to run during the day.

Truth is you only need the peak on a hot day. Some years, BM has no really hot days, others it is hot every day. If you decide to underprovision, you may find that on a hot day you need to disconnect some of the RVs and tell them to switch to their internal generators. This is cumbersome but may save you a fair bit of money, since most of your costs depend on the peak load.

Also tell people to not leave AC on when not in their vehicle, and to switch their fridge to use propane only during the event. (This is more efficient and keeps the fridge colder, anyway.) And also to turn their AC off if they want to microwave for a few minutes. Few people do long-term microwaving in the heat of the day. This is also important advice for anybody plugging an RV into a 15A or 20A socket.

In fact, you can point your RV campers to my page on how to connect to camp power which also guides tent campers.

If you decide you want to do this by waiting for a breaker to blow, be sure to overprovision your wire a bit. You should also bring a clamp-on AC Ammeter. Such meters can measure AC current in single conductors by just closing a little loop around the conductor. You can use this to track the load on any of your legs. Also get yourself a few "Kill-a-watt" units for people plugged into edison plugs. You can quickly track power, amps and even kwh. Get the more expensive one that has a backup so it tracks kwh even when there are power interruptions. If you trust your campers, you could even bill power by the kwh.

Appliances

With power, appliances can come to the playa. Fridges draw 400 to 800 watts but not all the time, so their average load is more like 200 to 300 -- pretty affordable on a large generator and very handy for your kitchen and drinks. Chest freezers also average 150-200w. Swamp coolers only use 90 watts instead of the 800 to 1,500 big ACs use. Heat-based appliances (toasters, hair dryers, etc.) don't really have much role during the daytime on the playa, I hope.

Pricing

The RVs and other big power draws are the main driver of cost. They should pay the lion's share, but in fact it will still be cheaper for them than running their own generator for half the time they will get power from the grid.

At the same time, the whole camp benefits from power, which powers your general camp lighting, kitchen, any artwork that needs power, music etc. So a contribution from individual campers also makes sense. They will use it to charge their batteries, and can be encouraged to have lighting, fans, swamp coolers etc. in their tents and chill spaces.

We have used a system of allocating shares. One share per camper, and 6 to 8 shares per RV, plug-in vehicle or other daytime power draw. (If it's 6 shares per RV, an RV with 3 people counts for 9 shares.) Then add up the power budget, including fuel estimates assuming a hot year, and work out the cost per share to put into your camp fee. We have often found something in the range of $8 per camper and $60 per RV works out for a large-camp biodiesel power grid. As noted, with many of the RVs, they would pay $3/hour or more to run their generator, plus $3/gallon of gasoline burned in it, so this is a good deal. You can tweak the shares if you like.

Your generator will list its fuel consumption rates at 100%, 50% and possibly other loads. When it's not hot it will be running at a very low load like 5% to 10%. If it gets really hot you might hit close to 100%.

You may decide not to run your generator after bedtime (2am?) and turn it on again when things get warm in the morning (9am). In that case you should have batteries to run lighting and minor stuff, or use RV generators during such periods. Or you may run 24/7. Most generators don't list their idle fuel draw, but it can be 1/2 gallon/hour or more on larger generators.

(Still, for those 6 hours of night, that's just 3 gallons or about $14 for the overnight power, usually worth it to have constant power if you negotiated the generator hours for it. And it offers the option of people running fridges and freezers for their kitchens, though that could be bad news if there is a long generator failure or fuel issue. Fridges can be saved by puting Arctica ice in them. Freezers in the shade should last many hours unpowered if not opened.)

Multi-Camp

It can make even more sense to share power among several camps. On the main theme camp streets, especially the Esplanade, almost all your neighbours will also have power plans. It's cheaper to rent thick wire and a bigger generator than it is to rent several smaller generators. It is, however, more work for the camp coordinating the generator and handling the funds on it. And a failure knocks out everybody's power.

If you do this you may need to trench if you want to cross borders or streets.

It is of course best to arrange this in advance, but we have always found neighbour camps eager to pay a share rather than have a noisy generator in their own camp. One camp will plan a nice generator, then upgrade it and ask the neighbours, "Hey, would you like to pay <half what you would pay to do it yourself> to have quiet, constant power?" They usually say yes. (Make sure they don't plan to use your power to keep you up all night playing bad dubstep super-loud first, though.)

Biodiesel and off-road diesel

Diesel generators can run biodiesel by using different fuel filters, but most rental companies will not allow you to run biodiesel due to policy. Kohler allows it, so we (and Burning Man) have rented from them. It has cost a bit more because they charge an obscene amount for shipping, but shared over many people it works out. (If you can find a supplier willing to run biodiesel and you can tow it yourself you can do this for little more than regular diesel.) If you tow yourself you must of course go to the rental company during business hours for pick up and drop off, have a tow vehicle, and be ready to clean and refuel the generator before drop-off if not otherwise arranged.

Bentley Biofuels provides biodiesel to the playa made from recycled vegetable oil -- about as green as you can get for a fuel-burning power grid.

You generator will run on off-road fuel which is cheaper because you don't pay road taxes on it. However, it is illegal to put any extra fuel you have left into on-road vehicles when you are done. If you are returning the generator empty (more common with biodiesel than petro) plan your fuel orders so that you will burn out all your fuel before you strike your power grid -- ie. sometime in the night on Sunday or early on Labour day, unless you need the grid then.

Usually expect to make some use of the generators in RVs for tools and other things before and after your power grid comes up.

RV Distribution points

Unfortunately, distribution boxes that let you plug in an RV are rare in the rental market, though this is improving. We have had to build our own.

You may find it's simpler to rent distribution boxes with 20 amp Edison receptacles, and plug your RVs into that. This will work for small RVs, and even for many large ones if they remember not to turn on the microwave or other such appliances with the AC on. However, using full 30 amp RV plugs and 10AWG wire is best. It's not unusual for the big RVs to find they blow the 20a breaker each time their AC starts.

We have used two approaches to this. One is to have distribution boxes with L21-30R receptacles on them (these have 3 hots, one neutral and ground) and build cables that then split out to 3 TT-30 receptacles. You just buy the 10AWG wire and make it all as a cable with 3 ends. (Note that distros with L21-30R on them may be somewhat harder to find, so be sure you have reserved those before you build such cables.) If you can do this it's a lot simpler and less bulky. RVs generally have a master breaker at their main power input, so they won't draw more than 30a (or whatever they are rated for) so you may not need two breakers close together depending on your cable size and the power the socket can provide.

The other approach is to build our own distribution boxes based on household circuit breaker panels. These are not very expensive, and can even be found used and cheap when pulled from houses due to remodels. Standardize on one type of breaker (such as Square-D) before starting.

In general these panels deal with 2 phases, and you will have a double 50A or 60A breaker on the main input. This will be connected to wires that run to a tempower, bates or other high-current plug, and thus can plug into the cables that run to your main distribution point. With tempower, which has two phases, connect one to each side. With 100A bates, just connect the 100A bates to both breakers, or use just one side of the panel.

Then fill the panel with 15a, 20A and 30A breakers. The 15A breakers should go on 5-15 plugs or any plug that will not have at least 12AWG extension cords plugged into it. 20A breakers can be used for plugs that will have 12 or 10AWG cords or RVs with adapters. 30A breakers are for TT-30 receptacles for RVs.

We then drill holes right in the panel box to mount TT-30, 5-15 and 5-20 receptacles right in the box, and wire with romex or similar inside. GFCI receptacles are a little more expensive, but can't hurt.

Many of these panels are not rated for outdoor use. While rain is rare on the playa, we simply took inexpensive rubbermaid storage crates and placed the panels inside, cutting holes for wires to come in and out to provide suitable weatherproofing. This is not to code, of course, so you may just want to get outdoor rated panels, but still protect them from dust and rain this way.

Clif Cox has prepared a step-by-step photo guide to building a distribution box for RVs. His example has 6 15a or 20a Edisons and 4 RV sockets on a 2x50a panel. You can usually do 5RVs on such (your 2 largest on one side the 3 smallest on the other side) and one or more RVs will only plug in at 20 amps. You probably don't need 6 of the standard dual-receptacles.

And here are some photos of a 3-way splitter cable for an L21-30P by Kurt Albershardt.

Cheating cable

Because each regular (not 50a) RV has a 30 amp master breaker, it's OK to plug an RV directly into a 50 amp circuit. So if you are using tempower spiderboxes, you will note they are pass-through, and have a tempower out socket. You can easily make a cable with one Hubbell tempower plug, and two RV TT-30 sockets. If you are not chaining further from the spiderbox, you can have two RVs plugged in for full power, and the rest into the 20 amp edisons. Don't do this if your RV does not have a 30 amp breaker. If you have a big RV with a 50 amp breaker, you could put a 50 amp socket on this cable (one phase or both) but don't use the 50a to 30amp adapter, because you could draw more than 30 amps through it and it's not rated for that.

Mistakes & keeping good

Plan for mistakes. Kohler sent us a generator not ready for biodiesel one year, and we had to rush in filters before we could run it. You may not get exactly what you ordered. Have a little spare wire and some tools. Have a way to contact people coming to the playa to bring things that are missing.

Have a fuel pump. Consider having containers to store extra fuel in case Sierra fuels (the on-playa delivery contractor) doesn't get to you at a predictable time.

Do a good job cleaning what you rent. I recommend use of a pressure washer (perhaps at a car wash) for cables covered with playa dust. We want the rental companies to be happy to rent to Burning Man again.

Owning vs. Renting

Renting can be quite expensive, and there is the temptation to buy some of the equipment, especially if you can use it at other times in the year. This can indeed make financial sense, but there is one big problem.

If something goes wrong with equipment you own, you may have no recourse to get it fixed. If your camp, and your art projects, are going to depend on this power, you must have a plan for what you will do if any part of it fails to function. That plan may involve extravagances, like sending people to Reno or even San Francisco, or paying for overnight fedex on heavy items (Yes, you can fedex to the playa if you know the right people.) It may involve having people who are coming to the playa standing by to get E-mails before they leave.

And it may also involve depending on the reps of the major generator companies. In spite of the remoteness of the playa, these companies are used to renting to people who want to use their generators in remote locations, and who will depend on them. It is part of why you pay extra for a rental. Stuff fails on the playa a little more often, and fixing it is a little harder, so this may be insurance worth paying for. If you plan to use stuff you own, consider hunting for insurance that will cover rare but burn-ruining conditions.

And of course, also have backup plans. If you have to, use RV generators or other portable generators you may also have. Be sure you have at least one to power your absolute essentials like camp lighting. Consider having batteries (I mean large deep cycle ones) to power other lower-power essentials.

Where to Get Stuff

If you plan in advance, you can wait for equipment to show up on eBay, including household panels, circuit breakers, TT-30 receptacles, Hubbell CS6365 plugs, and if you want to buy for the long term, cables and spiderboxes.

You can also find most of this stuff, including all the panel stuff and TT-30 gear at stores like Home Depot.

Use web shopping engines to find Bates connectors, like the 100M. Check your area for rental outfits that cater to the theatrical and music industries for rental of such equipment, or check houses that rent generators and distribution equipment to contractors.

Examples

In 2005 we built a single-village grid with a 60KW generator. In violation of code, the generator supplier attached some tempower twist-lock receptacles directly to the generator bus (no breaker), and we ran 100' tempower cables to our RV distribution boxes around camp. We ran in 3-phase mode. These boxes had breakers, but there was a risk a short in one of the tempower cables could melt it. The 60KW generator was capable of 170 amps per phase. We received a movie quiet generator from the supplier (ordered a regular) so we were able to place it next to camping areas.

In 2006 we built a larger grid for 4 camps from Kohler using biodiesel. We placed on on the other side of the street in an annex. For the main camps, 4/0 wire was trenched to distribution boxes with tempower jacks and others with L21-30R jacks. We used 1/0 feeders provided by Kurt. We then used tempower cables to lead to our RV distribution panels, as well as 3-way splitter cables. We burned 300 gallons of fuel for about 300 campers and 30 RVs. It was not a very hot year. Fuel was $3/gallon.

In 2007 we constructed a huge power grid for 7-8 camps with a 175kw generator. Its output -- up to 600 amps per phase -- was fed directly to a master 600A distribution box, and runs of 4/0 wire fed out in several directions. After a 500' run of 4/0 into Camp I Am, we split into a 100' run of #2 5-wire banded for Camp I Am, and longer runs to provide other camps. At various points, splitters were used to feed Bates distros which featured 100 amp stage pin receptacles. (Entheon actually rented a trencher due to the amount of trenching required.)

25 and 50' 100 amp bates cables were used to lead to distribution points, either our own RV panels (rewired so the 100A hot lead fed both 50A sides of the panel) or to other distribution points which either offered "lunchbox" (similar to spiderbox) collections of Edison receptacles or more bates power.

In another section of the grid, distribution panels with L21-30R fed a wide array of RV splitter cables. These cables don't provide Edison receptacles, so people needing those plugged into the RVs.

We burned about 1170 gallons of fuel for about 800 campers and 70 RVs. It was a hot year. Fuel was $3.50/gallon on playa.

Blowing your big breakers

If you overload your main generator or a major distro you probably can't just turn it all on with one reset of the breaker. On many generators there is a relay in the control panel you must reset the pin on before resetting the master, but that's only part of your problem. You will need to switch off most of your sub-feeds and bring them up one at a time to avoid doing a huge load all at once. It won't hurt if you tell people to turn off ACs and wait for power before turning them on again. And of course you must not turn on as much stuff as overloaded things -- in fact it will be worse because all the ACs will be on the same cycle.

In addition if you let things stay off for a few minutes the pressure will reduce in the ACs and make them easier to start.

Much smaller generators

If you don't plan to help RV folks run their air conditioners, you can get by with much less generator power. I've often wondered if this is not wiser, though it means on hot days you will get all the downsides of lots of RVs running generators. If you do this you still need good wiring, and you should be ready for people turning on ACs by mistake. And folks will run kilowatt power tools and the like. Some RVs surprisingly tend to draw 200 to 300 watts just sitting there, especially if they don't put the fridge onto propane mode. I don't know if this is just inefficient 12v systems or what. It's surprising how nice it is to have 24/7 silent power in an RV even if you don't use the microwave and AC. And it's good not to have people fire up a generator just to plug in a minor appliance or tool. (I've seen people fire up generators to run low-power battery rechargers or soldering irons or computers.)

If you build a low power grid, with perhaps 1 or 2 6kw generators providing a network of tents, non-AC using RVs and main structures, it would be good to hear your experiences.

Random notes

  • Bates connectors do not twist-lock, so duct tape them, or if they have strings on them, tie them to what you plug them into so they can't be pulled out while live.
  • Never connect or disconnect live connectors under load. Either remove the load, or throw breakers first. That's one reason to make sure connections are secure, so people can't disconnect by tripping on them. That can arc and fuse the connectors!
  • If you have a major camp, you may be able to get DPW to loan you a trencher for a short time during setup. Bring nice bribes (single malt scotch) to facilitate things.

Thanks to Kurt Albershardt for contributions and some of my own education on this matter.

Checklists

Here are some things to have on your list:

  • A suitable rental generator, with enough power for your loads -- 2kw per RV plus other loads. Add 50% if you plan to run in the simpler "single phase" mode as in that mode you only get 2/3 of rated power.
  • Somebody who will pick it up and get it to the playa, and clean and return it, during rental company office hours.
  • An arrangement with the Burning Man official fuel delivery supplier.
  • Possibly an extra fuel tote and fuel pump if you have a high fuel consumption and need to worry the fuel guy might not come one day.
  • Your high-current connection to the generator. Either Hubbell in single phase mode, or camloks in three phase mode.
  • Suitably thick cable (4/0 or 2/0 usually) from the camloks to your "master distro"
  • Your master distro, which will feed your loads or other distros. (You may fan-out or do a daisy chain with some equipment. If using camloc cables, you may use 2fers or 3fers to fork lines out to your local distros.
  • Suitable thick cable to your local distros. Camlok, tempower or Bates stage pin.
  • Local distros, which you probably built yourself. They take as input the above cable, and have plugs for equipment, and probably TT-30 plugs for RVs.
  • Sufficient 10AWG extension cables to reach the RVs fgrom the local distro location. RV extension cords will work.
  • Other extension cords suitable for your other loads.
  • Extra fuel and air filters. It's dusty.
  • Voltmeters and clamp-on ammeters to measure current. Kill-a-watt units for small load measurement.
  • Backup plans -- how to use RV generators in a pinch.

Simple "Tempower" Single phase grid

  • Your generator, configured in single-phase mode. It will deliver only 2/3 of the rated power, so if you get a 60kw generator, expect to power perhaps 20 or so RVs.
  • The generator will have Hubbell "tempower" sockets on it. Each one can provide 2x50amps, or about 12kw.
  • Enough tempower cables (which your rental place can rent you) to reach your distribution points. YOu can get 100' and 50' cables. Beware you can only go so long, though.
  • Distribution boxes. The easiest thing is to rent "spiderboxes" which plug directly into tempower cables and provide an array of 20 amp standard edison plugs. You can plug most small RVs into such boxes at 20 amps each. Most RVs come with a TT-30 to edison plug adapter, but if you can get one that goes to the 20 amp rated plug that's even better.
  • Alternate: Your own custom distribution boxes that taken in the Tempower plug and have RV plugs. YOu can plug in 5 RVs this way. Put the 3 smallest RVs on one phase, the 2 largest ones on the other phase.
  • 10 or 12awg extension cords for edison plugs, or 10awg RV extension cords to reach your RVs and deliver 20 amps. Note at 20 amps you can't run other electrical loads like your microwave while running your air conditioner.
  • Also bring 10AWG or 12AWG extension coords to plut in RVs and other load directly into the 4 standard edison receptacles found on most generators. Check your generator specs.

Budget 3-phase grid

For a 3 phase grid, get a generator configured in 3-phase mode. Your Hubbell sockets will not work. Instead, read camlock lugs with the generator. Get 5 lugs, including a green one for ground, white for neutral, and usually black, red and blue for the 3 phases.

Also rent lengths of thick camlock cable to feed from the generator to distribution points. Get 2fers or 3fers to split off the grid into forks. If you ahve 3 distribution points you can run one hot phase to each point, and use a 3fer to split the ground and neutral to go to all 3 points. Your neutral will need to be much heavier cable on the common link. Your hots will need to be rated enough for the distance of line and maximum current per phase.

3-phase grid with Stage Pin

  • Get a a Bates distro which takes in the camlock feeds and allows stage pin cables -- perhaps the 100a kind.
  • Get sufficient stage pin cables to go from this master distro to the local distros.
  • The local distros will have either edison cables, or smaller stage pins, or will be custom panels you made with RV TT-30 plugs. Here, with just one phase, you will just put 5 RVs, or possibly 6, on the 100 amp link which will be one phase.