Generator for a small bouncy castle in a park?

July 13, 2022 5:18 PM

I'd like to DIY a bouncy castle in a park for my kiddo's birthday party. How can I power the fan?

I'd like to buy this Little Tykes "small" bouncy castle, which is about 80 inches square. It comes with a blower fan. How can I run power to it in a park?

I'm going to choose a public park with low traffic - it's a soccer field, not close to a playground, on a weekday morning. We go there a lot and it's pretty deserted.

Is there some a kind of battery or generator that:
- has enough power to run this blower fan for about an hour
- is not hellaciously loud
- doesn't require anything icky like gasoline?

Any other tips for bouncy castle fun would be appreciated, it'll be my first time being in charge of one.

Thanks!

posted by nouvelle-personne to Technology (11 answers total)

I think you are going to need an icky generator…

That’s a lot of fan running for a substantial amount of time. I hope there are better alternatives, but. That’s a lot of blowing.
posted by Windopaene at 5:25 PM on July 13, 2022

You want to rent a generator. You’d probably find one at a heavy-equipment and tool rental place like United or Sunbelt. Looks like Home Depot rents these too. The specific model you want is a Honda 2000, which is a “suitcase” generator. It’s quiet enough not to be a nuisance. Do not get a “cage” or “jobsite” generator.
posted by adamrice at 5:41 PM on July 13, 2022 [5 favorites]

If you're going to let kids go inside the thing, you don't want to DIY. What you're renting isn't just the equipment, it's also the liability insurance. If a kid gets hurt while inside, or falls off, you don't want to get sued.
posted by decathecting at 5:55 PM on July 13, 2022 [6 favorites]

Regarding "any other tips" ...
I recommend that you protect yourself by checking with the owner of the soccer field (maybe your local parks dept.?) before you proceed, to see about legalities/rules regarding use of the soccer field for an endeavor such as this. For example, pounding stakes into the soccer field's ground might be prohibited.
posted by SageTrail at 6:02 PM on July 13, 2022 [5 favorites]

I'm eyeballing, but this similar product has a review that specifically mentions using a portable battery generator (Jackery brand, specifically). The downside is that portable battery generators cost almost a dollar per watt so $300 for the Jackery 300 (very small, I use it to power/charge small electronics for maybe 20 hours when camping) and $1000 for a Jackery 1000.

Specifics from the review:
"Blower can be operated off a battery power station
-- Using about 320W – 370W, bouncer could last for approximately:
--- 45 minutes with Jackery Explorer 300, though the 320W – 370W would stress this battery’s 300W capacity and shorten its life more quickly over time
--- 1.25 hours with Goal Zero Yeti 500x
--- 2.5 hours with Jackery Explorer 1000"
posted by Lyn Never at 6:21 PM on July 13, 2022

Go to parks and look around for an outlet. They may be found near band shells, picnic shelters, maintenance sheds, etc. Bring something you can plug in to test if it's active.
posted by fritley at 6:26 PM on July 13, 2022 [2 favorites]

My pickup Truck, F-150, has outlets that can be used to power the fan. Find a F-150 Lightning (EV) and it IS a generator.
posted by JohnnyGunn at 6:33 PM on July 13, 2022

Also, I know of no toddlers that could do that for an hour straight. I think if you can get 30 minutes, even 20 minutes, you are doing well. At one point, my kids were 3, 4, and 5. Put the three of them in this thing and guarantee that within 7 minutes, one will be crying, one will be tired of it and one will just keep bouncing away.
posted by JohnnyGunn at 6:36 PM on July 13, 2022 [1 favorite]

There are several reputable manufacturers of reasonably large battery packs on wheels that will power your load for several hours. The biggest concern, other than buying from one of the reputable brands so it's less likely to turn into a flaming fireball in your basement, is that it needs to have a sufficiently large inverter capacity to deal with the 700-800 watts the blower will draw on startup. If it's undersized, even if the battery capacity would be sufficient for your needs (say you only wanted to run it for 20 minutes, in which case 300Wh of battery would be plenty) if the inverter is too small it will trip off when you try to start the blower.

Personally, I'd go with the battery pack over a gas generator unless you need to be able to run it for many hours a day. Even the quiet Honda generators are still annoyingly loud, you have to deal with gas and draining the leftovers when you're done if you want to be sure it will work again in the future, and they spew pollutants into the air that nobody needs. There's already enough NOx and PM2.5s in the air, thanks.
posted by wierdo at 7:48 PM on July 13, 2022 [1 favorite]

No recommendations here but a few thoughts:

- I think the power requirements are 115V (AC), 60 Hz, 3.8A, 437W (same 620072 base SKU, different suffix). Start up current will be higher.

- If you go with a car type battery, you'll also need an inverter. This random Google-find has inverter FAQ with a calculator for run time.

- A few weeks ago I set up a Honda EU 2000i generator to run a neighbor's refrigerator... I could not run the generator in quiet mode (ECO throttle) because that mode has a slow idle that sometimes stalled when the refrigerator started (250W Run, ~1400W Start). You have the advantage of only one start so you can switch to and leave it on ECO throttle almost immediately. If renting, consider the much quieter Honda EU 3000is (warning: its a heavy lunk)
posted by tinker at 11:50 PM on July 13, 2022

The installation manual on the page for the bouncy castle you linked confirms that the blower is rated at 437W. So if you wanted to run that for an hour, you'd need 437Wh of stored energy to do that.

At a car battery's nominal 12 volts, 437Wh translates to 437Wh / 12V = 36Ah and if you were indeed using a car battery you wouldn't want to run it down below 50% capacity. So you'd want to be starting with a fully charged car battery good for 72Ah at the very least. Allowing for assorted inefficiency losses in inverters and whatnot, a 100Ah battery should be good enough.

You'd also want to oversize the inverter. Expecting an inverter rated at 500W to supply 437W continuously for an hour or to cope with a typical motor load's peak startup power is overambitious, so I'd go for an inverter good for at least 1kVA.

Portable "generators" that actually consist of a fairly chunky lithium-ion battery pack with an integrated inverter are a thing now, and you might well be able to rent one for the day. As long as whatever you rent is built to deliver at least 1kW of power and 0.5kWh of energy, it should be good enough.

And yes, an F150 Lightning would run that bouncy castle blower continuously for an entire weekend without even breaking a sweat, so if you know somebody who has one of those, just use that.
posted by flabdablet at 5:37 AM on July 14, 2022 [1 favorite]