Huge CPU and Memory usage compared to Chrome browser on desktop

[mahim]

I’ve been trying to make a shift from Chrome to Brave browser as my default desktop browser - that is easy on CPU and consumes less memory - however, I’ve noticed brave uses huge amounts of CPU and memory resources.
To establish the fact, I tried to compare with Chrome browser [having 10 active extensions] opened with the exact no. of tabs [9 tabs] on both Chrome and Brave browser [only 5 active extensions] at the same time. I have a 12gb RAM machine and it started heating up after some time of use.
Both CPU and Memory in brave browser [with the only a total of 18 active processes - and this excludes the background process in brave] was comparable to Chrome browser [with 28 active processes]!! Is there a hidden process going on behind scenes for Brave browsers - such as crypto mining or something - why is using such huge resources - which is also impacting my machine battery life.

Description of the issue:
How can this issue be reproduced?

1. Open 9 tabs [including Youtube] each browser
2. Use Brave browser with 9 extensions [password manager, Tab suspender, Grammarly, RainDrop, Email Tracker] and Chrome browser with 10 active extensions [adblock for youtube, password manager, google keep, unlock, Grammarly, Onenote, Session buddy, great suspender, Email tracker]
3. Open Task Manager to monitor CPU and Memory columns

Expected result: Brave browser with low active processes- still uses higher / at par CPU and memory as Chrome with way more active processes running

Brave Version( check About Brave):
Version 1.11.97 Chromium: 84.0.4147.89 (Official Build) (64-bit)
Additional Information:

[fanboynz]

I would test with no extensions (in case its just a buggy extension), or a clean Brave profile.

For any browser, it also depends on how large/complex the webpages are (whether it needs more cpu/ram) to render the page correctly.