Over the years for burning man, festivals and campouts, I’ve spent a huge amount of time and resources experimenting with battery-powered solutions for lighting, camp-charging, and bike/small vehicle power.
I’d like to share some tips and tricks that I’ve learned. Whether you’re planning to power an art installation, a bike, a festy wagon, or all your camp’s charging and lighting needs, I hope these tips can help you take your projects to the next level!
canuzzi - solar-powered pump canoe hot tub
POWER TIPS FOR ART PROJECTS & END TIMES
Throughout this post, I've linked to items available on Amazon as of August 2018. Some of these items may change over time - sorry I can't be responsible for keeping the links up to date, but if you have questions, feel free to email us.
LOW POWER NEEDS
If you are running 5V LEDs or drivers and you are under 2A, you can use USB power banks - super easy :) Sales plug here, we’ve got good ones for $25 that have 2x 18650s that are swappable and can also be used to charge the batteries.
small usb power pack powers our sign for festy wagon!
HIGHER POWER NEEDS :: CONVERTERS & TRANSFORMERS
If you need more power or voltage, a DC-DC converter can usually handle a wide input voltage range and support either battery. Note that these converters will constantly draw a small amount of power when hooked up, and have no low-voltage cut-off, so they will over-discharge your batteries if they do not have protection.
For 5V, I recommend a DC-DC buck converter. You can get them on Amazon. I’m in no way affiliated to these guys, but if you do buy on Amazon, please support Fund the Flow Arts, through Amazon’s smile program :)
For 12V, even if your battery is 13V, you might overheat your LEDs, or damage a sensitive driver. I recommend using one of these - they’re also great for golf-cart/EV lighting.
Pretty much any one that looks like that tends to work, I’ve seen them up to 30A, and you should aim for 2x your power need to safely handle heat, especially on the playa ;)
Smaller/cheaper DC-DC converters that have tiny or no heat-sinks or require fans are much more prone to overheating and failing, often passing full-voltage into your project and frying half your installation. Be careful.
Double-triple check everything. Don't get sloppy at the last minute, or during a late-night repair. Reverse polarity or over-voltage can easily fry all your work. It happens to the best of us.
- Cordless power tool batteries can be nice if you already have them, they have built-in over-discharge protection, but are awkward shapes and hard to connect to.
- 3s-4s LiPO hobby batteries are the second cheapest source of li-ion power, work great and sometime have built-in protection - make sure yours do, or add some.
- 18650s are the cheapest source of li-ion power, but need to be combined into packs for most purposes, also there are loads of counterfeits and false claims on these cells, choose carefully from a reputable source. If it seems too good to be true, it is.
- 12V SLA/deep cycle lead-acid batteries work great and are cheap, but are heavy and need protection.
The cheapest/easiest high-power protection for SLA/deep cycle lead-acid batteries I have found is in solar charge controllers, like this one.
Watch out for more complicated cheap controllers that have load-control options like dusk-dawn, in some cases they reset when power cycled and have very hard to understand navigation. They will very likely leave you wondering why the heck your light won’t turn on when your battery is charged, or turn off after 1 hour, or when light hits your solar panel, etc.
the iconic flowtoys mobile vending cart - runs on a lead-acid battery
You can also use one of the cheap 100w flexible solar panels that are popular right now and a deep-cycle battery for a fairly cheap and easy alternative to generators for most camp-power needs! Or you can spend 2-10 times as much for a system that is 10-30% more efficient and will last longer if you take care of it.
Tip: Wipe off the playa every day for way better output!
The one thing worth investing more in would be the charge controller. Get a “morningstar” brand one that meets your needs. Add a 5V DC-DC converter to some powered USB hubs or go direct to 12V adapters or cigarette-lighter adapters like these (random quick-search cheap examples, shop around a bit!). You can just cut some cords, use a bunch of wire-nuts, or get fancy with fuse, switches etc., and you will have silent clean charging for all your camps devices :)
CONNECTING EVERYTHING TOGETHER
Calculate your ACTUAL amperage and use an online wire-gauge calculator to determine the appropriate wire gauge for your project.
Remember it might be nice to run all 5000 of your LEDs at full-white with no voltage/brightness drop, but if that means all your wire and power supplies need to be 4x bigger than your brightest rainbow pattern requires, it might not be worth it. On the other hand, if a bright pulse crashes your system, that’s not worth it either, so test your actual needs on a smaller scale, or full scale if possible.
How much voltage drop you’re willing to accept is up to you and can vary widely depending on the situation. A 0.5V drop on a 5V run will be 10% of your power wasted, as long as you have enough voltage at the end of your run, even a 20% power loss might be acceptable if it’s only during short periods of the highest power draw.
But every chain is only as strong as its weakest link. If your wire will likely be physically damaged or weakened through normal use and flexing, you might want to consider a larger gauge. Even more important are your connections …
Wire connections - Here are some options:
> solder and heat-shrink: Great when you have the time, and materials to do it right and don’t plan to take it apart.
> screw terminals of any kind: Great when you have the time and materials to do it right, but they are very gauge-dependent and often creates a weak electrical connection because they do not really surround the wire and can also physically damage it and create a stress-point.
> wire nuts: I’m a huge fan of wire nuts for medium-gauge wire and hidden/protected connections, but you need to twist them till your fingers hurt (the ones with wings help a lot!), or use pliers, just don't break the wire. And ALWAYS test by trying to pull out each individual wire from the nut. I’ve done thousands and still mess one up once in a while. There is no visual check!
> lever nuts: Super easy and convenient for hidden/protected connections, but same weaknesses as screw terminals: very gauge-dependent and often creates a weak electrical connection, because they do not really surround the wire, physically damage it and create a stress-point.
- For under 3 amps these JST connectors are the most reliable, common, cheap, and easy to use solution I’ve found. You can use the crimp-on ones for cleaner wiring, but they are quite fiddly and I find the ones with leads faster and easier to implement.
- for 3-4pin power and data, these are the most commonly included on LED strip for good reason. As crappy as they seem at first, they are the best cheap solution I’ve used.
- for more durable/water-resistant connections, check out these connectors.
- There are many other connector options, but once you get over 3-5 amps, I highly recommend “anderson powerpole” connectors. They are universal, physically symmetrical, incredibly versatile, reliable, and widely-used.
anderson pole connectors
Be sure to check the standard configuration to be compatible with accessories and other people’s plugs.
The crimper style recommended by the connector manufacturers works pretty good if you use the correct gauge wire, but with a little skill you can crimp pretty much any amp connector to even the thinnest wire using one of these much cheaper and more versatile crimpers.
A good crimp on clean wire is not just faster, easier, and more compact, but also electrically better than solder, if it’s proper! The wire should be crushed to the point there are no air-gaps. Always test your crimps by trying to pull them out - hard. A weak crimp or connection is the most common fail point in any project - sometimes just dropping enough voltage/power to cause intermittent failures, and very hard to find later!
If you want something cleaner and more user-friendly during regular use the MT30 and XT30 are a popular alternative to the powerpoles, and come in larger sizes as well, though they are a bit harder to implement and less versatile (not symmetrical/reconfigurable or crimpable) I think the MT/MX could be a better choice for long-term installation with frequent handling.
> strain-relief: Remember the weakest link! In the case of break-down this might be your highest stress-points, which are probably where your wire enters your connector, especially if the connector is mounted to something. In-line connectors generally have less strain on them.
I’m in love with adhesive-lined heat-shrink for strain relief! So quick and easy and very effective! It’s also easy to remove, the hot-glue doesn't really adhere, it mostly fills, so it’s not for true waterproofing, and can separate from the wire a bit over time if it’s not a single round wire, but that’s never been an issue for me.
HAVE FUN WITH YOUR PROJECTS!
I hope these tips give you the power to (pun intended) make some cool things happen! Please feel free to share pics of your projects with us.
- Sean von Stade :: flowtoys, founder
the pod wagon - our festival mobile family wagon - carries our kid and all our gear, and is a great way for friends to find us :)
battery-powered bike lighting