M1 MacBook Air energy usage

I have a 2020 MacBook Air M1, configured with 7-core GPU, 8 GB unified memory, 256 GB SSD. Pretty sure it was the lowest configuration as I was still a student on a tight budget. FYI, it’s currently running macOS Ventura 13.3.

Starting August of last year, I have had to use my Mac for many hours every day for work, and it’s always performed fine up till now. However, since a little while after updating to macOS Ventura I’ve noticed an incredible amount of energy usage; my battery (health at 91%) lasts me nearly eight hours if I’m lucky. This is clearly a far cry from the 18 hours of rated battery life, which I was easily able to get several months ago. What’s intriguing is that I don’t do anything more than browse the web in Safari with the same seven tabs open every day; occasionally doing a bit of light coding with Python, which requires use of Google Chrome, when necessary; and working with spreadsheets and documents in Microsoft Excel and Word. None of these seem to drain battery faster than the others except when watching a video (e.g. YouTube tutorial); I just glance up and my battery is down from 100% to 87% in ten minutes. My Mac is always connected to strong Wi-Fi, except while in the car to and from work. Not sure what on earth changed with it since the update, but it’s making it hard to get through the day without taking along my big power brick and USB-C cable.

Anyone have an idea what could be going on? I’ve checked Activity Monitor to see if there are any obvious red flags, such as the common complaint of Chrome hogging CPU, but the whole system is basically utilizing two M1 efficiency cores for nearly all the tasks and rarely touching the performance cores. CPU usage stays under 10% for all tasks. The GPU has one core working slightly and the others are under negligible load. Storage has plenty of room as I use iCloud for everything possible. The only thing I see odd is that nearly 6 GB of the RAM is in use, with only 2.01 GB still available, and I’m not actively using any apps other than what I’ve mentioned so this seems a little strange. I do keep Mail, Messages, and Notes running (not quit) but not active/open. Anyway, any input or suggestions would be appreciated as I’m sure there’s plenty more I could check since this is a family Mac and family members may have downloaded stuff I wouldn’t prefer to have on there.

Thanks!