I was attempting to tidy up my one of my hard drives and noticed a huge discrepancy between the usage for the drive and the file size of my project files. 300+ gigs were unaccounted for until I tracked down an Adobe After Effects folder inside My Documents that had 351Gigs worth of Peak files. Some of them are labeled by project and some are numerical.
Can I empty the whole folder even if some of the peak files may be for active projects?
If I do delete them will they re generate when I open the project again?
This page should answer your questions:
The short answer is that, yes, you can safely delete these files. You just may have to wait a while the next time that you use the associated assets, while the new media cache files are generated.