Advice on extra USB hub for Lenovo Desktop

I want to purchase a USB hub with 4 USB 3.0 ports as my Lenovo Desktop computer (Windows 10) which is plugged in to an electrical socket does not have enough ports. When looking online, I see that some adaptors come with either 5 or 15 watts. However, I do not know anything about wattage and volts!

I have read that it is better to have an adaptor with the USB hub, so the desktop battery does not get drained. However, I do not know if I need a 5 w or a 15 w power supply adaptor or to find out on my computer what would be compatible. Please note that we live in the UK. I want the extra ports so besides using a mouse and keyboard, I can use a desk fan, printer, scanner, ab external hard drive and computer stick, etc. without having to take one cable out of my computer to be able to use another. We do not have other equipment, such as a mobile, that needs charging.

I just do not know which adaptor would be the right one/compatible for the UK and find the information I see on Amazon UK most confusing. I like the idea of turning off a port if I do not need it, but I do not know what would be best for supply adaptor to buy with the USB hub.

Any advice or help would be most appreciated. Please write in simple terms, as I am a pensioner and not a computer geek or an electrical genius. Thank you.

If only one USB device drops out momentarily due to insufficient power output capability of the USB port, you may experience unexpected behavior across the entire chain of USB devices until you have reset them all, and possibly have to reboot in order to achieve that. This is why an externally powered USB hub is the way to go if using multiple USB devices each one of which consumes varying amounts of power so the total power requirement also varies as a result, a lot often typically.

Don't skimp on a powered USB hub... I highly recommend this one right here:
Powered USB Hub RSHTECH 4 Port USB 3.0 Data hub +1 Fast Charging Port Aluminum USB Splitter with Individual on/off Switches and 12V 2A Power Supply (5 Port- Black): Amazon.co.uk: Computers & Accessories

Thank you for your advice.

zero2100 said:

some adaptors come with either 5 or 15 watts.

Choose 15 watts if you want to do the following:

zero2100 said:

use a desk fan, printer, scanner, ab external hard drive and computer stick, etc. without having to take one cable out of my computer to be able to use another.

Megahertz said:

As you have a desktop, it should have USB ports available inside to use on rear or on front bracket.

My power-hungry WD HDD does not spin up when connected to a USB port on the front panel, while my power-saving Seagate HDD works fine on the same port. It is unknown whether the OP's external hard drive is hungry for power.

Megahertz said:

A USB hub not always work as it should.

Recently, my Seagate HDD dropped out on a USB hub, causing the following: