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Two Chauvet 4-Bar fixtures powered by a Jackery Explorer 1500 power station on the author’s back deck.

Unplugging From AC, Part 5: Let There Be Sound … Joined By Lighting

If you’re in one of the 99.9 percent of acts who just need to put some lights up on stage or dance floor to get the party going, then you’ve come to the right place.

Editor’s Note: If you’re just joining this series in progress, you make want to go back and check out Part 1Part 2Part 3 and Part 4. In the meantime, here are the basics…

Many venues are opening up after Covid put the hammer down on gigs for the last two years, and with it there’s been a maelstrom of special events that are attempting to find a space for things like wedding receptions, class reunions and even block parties. There’s a log jam of events that need to happen in the next year and not enough places to hold them all.

Even though the price of gasoline and groceries are going through the roof, the public is desperate for experiences after being cooped up during the pandemic. Just look at airline travel and how crowded the beaches are. And when I drive by the chain restaurants in my area such as Red Lobster and Texas Roadhouse, the parking lots are always full up. So, at least at present, enough people are willing to spend money on food and entertainment, which is where you come in.

As I’ve detailed in the first four articles of this series, there have been huge advances in battery storage over the past few years. Lithium technology has provided a super lightweight battery with a pure sine wave 120-volt AC inverter that you can pick up with one hand, but which can power stage amps and a reasonably sized sound system for hours. That means you can now do gigs and party events at the beach, in the woods, or at a parking lot far away from an AC electrical outlet, all without having to drag along a generator with exhaust fumes and noise.

And the 120-volt pure sine wave output of these modern inverters means you can use existing stage gear and sound gear without any hum or buzzing like used to occur with earlier MSW (Modified Sine Wave) inverter technology. But what about lighting?

Back in the 1970s I built a 50-kW lighting rig with 48 1,000-watt PAR lights and a 2,000 watt-second strobe from an airport landing strip. It would take every bit of a 100-amp 120/240-volt service for a big gig and it was certainly fun to deploy with my hard rock band. However, I would never consider trying to run any kind of concert lighting from a portable power station like we’ve been discussing over the first four articles. But nowadays our lighting needs are more modest, especially for wedding receptions, class reunions and pool parties.

Enter LED Fixtures

Just like modern class-D audio amplifiers use a fraction of the power of those ‘70s amps, LED lighting only require 5 to 10 percent of the power needed compared to their tungsten ancestors. And a single LED fixture can be instantly programmed to produce any color you like without resorting to changing gels. I do hate changing gels and lamps on a hot lighting instrument…

Now, if you’re an A-List lighting director for a major act, you already know all this. And you’ll be thinking all about movers and blinders and video walls. If that’s the case then this article really isn’t for you. But if you’re in one of the 99.9 percent of acts who just need to put some lights up on stage or dance floor to get the party going, then you’ve come to the right place.

How much power do the new LED fixtures need? I happen to have a pair of Chauvet 4Bar lights in my practice room with a total of eight LED instruments that can be controlled with a foot pedal for basic color changes, blackouts and music (blinking lights) mode. This is great for smaller-scale gigs happening far away from an AC outlet.

For this test I simply hooked up both 4-Bar fixtures to a Jackery Explorer 1500 power station on my back deck, turned on all the lights on to a full 100 percent, and monitored the power usage for a few hours. And the results were really interesting, using far less battery power than I originally anticipated.

Also note that I discovered an inaccuracy in using a Kill-A-Watt meter to measure the kilo-watt hour usage of these fixtures. While the K-A-W meter reported 81 watts for all eight lights at 100 percent, the Jackery power meter reported 137 watts needed. This is likely because of the Power Factor issues created by the PWM (Pulse Width Modulated) dimmers in the LED lights themselves.

The Kill-A-Watt meter reported 81 watts for all eight lights at 100 percent, the Jackery power meter reported 137 watts needed. Hmmm…

The Jackery monitoring system appears to use a True-RMS power calculation, while the K-A-W meter uses a fixed Peak/RMS calculation. So, I trust what the Jackery meter is telling me for power usage much more than the Kill-A-Watt meter. But as they say, your mileage may vary.

The big question: how long can those lights run on a portable power station? With a 1,500-watt-hour Lithium battery in the Explorer 1500 and 130 watts needed for all eight LED lights at 100 percent, it should be able to operate for at least 10 or 11 hours on a charge. (Wow!)

Now, of course, you also need to power the stage gear and sound system, so let’s allocate at least 300 watt-hours – per hour – for music. This suggests that a 1,500-watt-hour Lithium battery power station could run a small band with a sound system and lights for at least three hours.

If the event is happening during daylight, you could plug in solar panels that can deliver up to 400 watts, which can add around 1,500 watt-hourrs of energy while the sun is shining. So that’s playing all day in the sunshine with perhaps another three hours of party time after the sun goes down.

More Ideas

I’ve contacted both Chauvet and American DJ about providing more LED lighting systems to test, and I’ve still not received an answer back from their marketing/press departments. But I’m reasonably sure that you could even add a few lasers and mini-mover lights to the gig if that’s your style.

The Chauvet GigBAR Move could be useful but needs to be tested.

The Chauvet GigBAR Move (and others like it) look like they could operate for hours from a Lithium power station, but I’ll need to run a few tests to know for sure. This may be more of a DJ thing (which I plan to cover in a future article), but I really do like getting a few movers going even for bands, so these pre-built LED lighting bars with movers are a possible way to add more lighting pizzaz that won’t break the battery piggy bank.

In addition, there are LED up-lights that are self-powered from their own batteries and under wireless DMX control. They’re not cheap, but if a band is doing receptions and corporate events on a regular basis (even where there are AC outlets available), these can great lights for adding atmosphere to the room without running cables all over the place.

Self-powered LED up-lights under wireless DMX control are another possibility.

This could also work for outside parties if you simply run the beams parallel to the ground. (Yes, I’ve actually done this, and it was really cool.)

What’s next? Coming up, I’ll be detailing some battery-powered gigs that I’ve already done using loudspeakers and stage amps How loud will they get and how long will they run on a single battery charge? Stay tuned for more experiments in unplugging a band from AC power.

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