On Azure, disk storage refers to Premium SSD Managed Disks. Encryption is turned on by default and uses platform-managed keys.
Disk Storage is $0.15 /GB/month, equivalent to $0.0002083 /GB/hour
Backup storage
Solutions deployed on Azure use Azure Files for storage. By default, backups are encrypted and decrypted transparently using 256-bit AES encryption, one of the strongest block ciphers available, and is FIPS 140-2 compliant.
Backup Storage is $1.25 /GB/month = $0.001736 /GB/hour.