An XPS 16 battery line showed no drain rate
On the XPS 16, the battery line and power panel showed no drain rate, because the script threw away the rate UPower had calculated. A change merged into quattro keeps UPower's energy-rate when that read does not return a number.
On the XPS 16 (N1x), the battery status line and power panel showed no drain rate. The firmware reports the present rate as unknown, every read of the kernel file fails, and the script worked out a 0W draw and threw away the rate UPower had already calculated. A change merged into quattro keeps UPower's energy-rate when that read does not return a number.
David Heinemeier Hansson reported the status line on that XPS 16 going from Battery 90% · 9h 12m left · 98Wh to Battery 89% · 7h 58m left · 11W / 98Wh. Machines that report a live reading are unchanged.