Powertop displays incorrect discharge rate on HP Envy X360

[daljit97]

When I run `sudo powertop` and look at the discharge rate of the battery (while my laptop is running on battery), powertop incorrectly displays a discharge rate of around 0.5W. The value doesn't really change much as time passes.

ProblemType: Bug
DistroRelease: Ubuntu 19.10
Package: powertop 2.9-0ubuntu2
ProcVersionSignature: Ubuntu 5.3.0-46.38-generic 5.3.18
Uname: Linux 5.3.0-46-generic x86_64
ApportVersion: 2.20.11-0ubuntu8.8
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Tue Apr 21 19:36:08 2020
InstallationDate: Installed on 2019-08-16 (248 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: powertop
UpgradeStatus: Upgraded to eoan on 2019-12-22 (121 days ago)