Fixing this WordPress bug I filed almost three years ago would also help reduce WordPress' memory and bandwidth needs:
"High memory usage ( and possible server error) editing post with many/large revisions"
https://core.trac.wordpress.org/ticket/34560
"The file edit-form-advanced.php has the following section of code which retrieves all revisions for a post using wp_get_post_revisions and then counts the result (twice) to display a count of revisions on the page. While the current approach has a certain elegant simplicity and is easy to understand, the approach is unfortunately computationally inefficient because retrieving all the revisions of a post just to count them potentially consumes a lot of memory, a lot of CPU time, and a lot of database bandwidth when there are many revisions of a post if some are of significant size."

I can speculate that this WordPress issue alone may be consuming the output of a mid-sized power plant given the huge number of WordPress sites out there?