With System Center Configuration Manager, you can retrieve a lot of information about your computers, specially the Hardware Inventory. And with Reporting Service Point, you can display it easily via a web page.
However, if you would like to display the Free space on a drive, you can do this but it is not enabled.
By default, when you execute the report “Disk information for a specific computer – Logical disks“, you will get a blank information about Free Space:
Hardware Inventory
To enable this option, you need to change the Hardware Inventory:
After that, wait for the Machine Policy retrieval and at the next Hardware Inventory, you will get the information.
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You can get more information on Hardware Inventory here