My laptop consumes 25 W of power when browsing on firefox(Ubuntu)

I bought a Dell Inspiron 3501 with 11th Generation Intel® Core™ i5-1135G7 Processor

I cannot complain on the performance of the laptop but the battery life is extremely short.

Looking on the system monitor I am at most at 10%
(System monitor )for all 8 CPU

but the power statistic shows a consumption of 25W
(Power statistic)

The previous data are taken during the laptop charge, when I was only using Firefox and no heavy web-site was running.

Moreover when I close the laptop I can feel that it is warm to the touch and leaving it overnight drains completely the battery

The battery life of this laptop is around 1.5 hours when in use.

Also doing a simple calculation of 42Wh battery capacity /25 W of power gives me around 1.5 hours so I confirmed the power measured by Ubuntu is correct

What do you think is the problem?

is it my machine, the model or some poorly configured software?