What kind of power supply do you need to run a Raspberry pi 4? Can it be run on a USB charger for example. I have an Anker 60w 6 port and also an Anker 2 port charger.
Would something like that be adequate to run 1 or 2 pi’s?
The Raspberry Pi 4B wants 5V 3A: Power Supply - Raspberry Pi Documentation
Those Anker ones only give 2.4A per port, so they won’t work.
do you have any recommendations for a good one, preferably for multiple pi’s
If you don’t mind spending a little extra, pick up a PoE switch + PoE hats for the Pi’s, then you can skip the plug-in PSU alltogether. It doesn’t have to be a High Dollar setup: Mikrotik, Unifi, Netgear, and others, all make affordable Non-Managed PoE switches.
@Jay has a series on PoE Pi’s in a k8s cluster, That could help select the PoE hats for the Pi’s.
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I really like https://www.amazon.com/MEAN-WELL-LRS-100-5-Switching-Enclosed/dp/B07DKCMJN9/ref=sr_1_7?crid=YKGIMBI5JNX0&dchild=1&keywords=5+volt+power+supply+meanwell&qid=1628128022&sprefix=5+volt+power+supply+%2Caps%2C242&sr=8-7 or any 5V power supply made by Meanwell. Just size it so you get at least 15Watts or 3Amps per unit. Then I just buy, or have on hand, enough USB cables to cut off and connect to the power supply.
It is pretty tidy and saves the cost of the POE hats. Pushing that much power down an ethernet cable for no good reason makes me nervous.
You don’t want to see my network rack then 
And while we’re on the subject of Power Consumption, those wall-wart PSU’s are rated not only for the CPU in the Pi’s, but the USB garb one hangs off them => 3 x 5 = 15W. That’s not a lot of power per device. Set aside what, 1.5 to 1.8 for USB junk, and you’re looking at ~1.8 x 5 = 9W. Again, not a lot of power for nic cables to handle, and they manage it easily.
Power isn’t magically used, it’s consumed (pulled) by something. The less you hang off it, the less it draws.
Edit-2 - RPI Power Consumption Matrix
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Maybe I have have just let out enough magic smoke over the years that I prefer my Meanwells. I come from an electronics background and recently started to dabble in networking.
I add a power switch and a fuse for each output to a Meanwell and put it all in a 3d printed box. I still have one that is in a 1/4 inch plywood box from before 3d printers were a thing.
Please don’t get me wrong, I love POE for cameras and APs. It is the best invention since sliced bread.
I probably sound like a crazy old coot who insists on emacs, ZFS or EEC memory for real work 
I might be crazy, but at least I am self-aware enough to realize that I am nuts.
This little switch right here: Netgear 4x PoE can deliver 30W per port. That’s nearly 2 RPI 4’s running at max draw (which is a very rare use case)
So, if you you only run 1 Pi on each of the 4 ports, you’re only using 50% of what the switch is capable of “safely” delivering. In other words, you have an 50% safety margin.
Edit - Sorry, I jacked my math up, was using the minimal draw of the Pi Only.
@mainedan Three different people answered with three different backgrounds with three perspectives A USB hub, a POE switch, or a switchmode power supply will all work. Just make sure each port can provide 15Watts per Pi.
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However, and all that being said, there’s no shortage of choice in the world of PI’s Whatever works is the best solution.
My background is also Electronics, 14yrs on Submarine comms, then Semiconductor industry, and now just writing code. I’m also an Advanced Class Amateur Radio Operator 
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Thanks for the suggestions, Ive wanted to play around with the pi’s since they first came out, but time was not on my side then. Now that I am retired, i am looking to get into them, and other aspects. I am no where near where basically everyone here is, I just like to tinker.
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Not a problem. Everyone starts somewhere. This group, while small, has a lot of knowledge in it. And a fair bit of opinion to go with it 
In all seriousness, if you get stuck, odds are somebody here can help one way or another.
Totally off-topic.
@KI7MT have you ever looked into modifying an AP to boost its power and send it over an ISM band.
One of my maybe someday projects has been to take an RC plane, add a camera and nice transmitter capable of sending back real-time high-resolution video to a remote monitor.
We have a fair bit of flooding in our area which requires the DNR and other agencies to send people out on foot to inspect the status of waterways after a hard rain. I always thought it would be cool to be able to do an initial arial reconisence with an inexpensive RC plane.
No, in fact, I try to avoid such devices in the ISM band (near field around the house) as I do a lot of extremely weak signal reception work (-25db to -30db) and RF Spectrum noise is a big issue. I don’t even like WiFi in the house / shop, but, it’s needed. I also use only shielded CAT cable to cut down on Network Radiation Noise.
I use devices like this one: Perseus SDR or RSPdx.
As luck would have it, the RPI’s are great companions for those SDR receivers.
Edit - But I would say, it would be a cool project, but just don’t run it near my house because I’ll know it’s up and running from the noise it generates.
You can get away with less than 3A, but you won’t be able to use the USB ports.
I, too, went the way to using PoE hats on most of my RPi’s. I bought a Netgear 8-port layer-3 switch (for VLAN support) and it works great.
One thing I think is important to remember when getting extension cords and power strips for all our computers is making sure the wire gauge is sufficient for our loads. I think a lot of ‘budget’ parts aren’t good enough. Older homes/apartments should be aware of their wiring, too. 
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Very good point @Buffy !!
As you can tell from my profile pic, I’m volunteer fire fighter. Most of our calls this time of year are for wild land fires. However, during the holidays it never fails, we get a call somewhere for an electrical fire due to wiring or overloading circuits (heaters, xmas lights, etc).
Keep the wiring neat, and understand how much each piece draws then add some safety margin to it. It seems obvious, but, many overlook or simply ignore it. Don’t be that person.
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