I'm not sure if the actual differences in energy usage are so clear cut. These charts [0], which account for the 12900K spending less time to accomplish tasks than the 5950X, seem to indicate the disparity isn't so terrible. You can always under-volt too; the 13th gen press release includes charts [1] showing that the 13900k at 65W matches the performance of the 12900K at 241W.

[0]: (Search for "cumulative amount of energy required to perform Blender and x264 and x265 HandBrake workloads") https://www.tomshardware.com/reviews/intel-core-i9-12900k-an...

[1]: https://arstechnica.com/gadgets/2022/09/intels-first-13th-ge...