While there will be extensions which increase power consumption the opposite is true for the most used category, that being content blockers. A well-tuned uBlock Origin will cut down radically on the number of requests performed per page, the amount of CPU time wasted on non-essential Javascript, the amount of GPU render time wasted on presenting those horrid moving monstrosities called ads and the amount of energy wasted by the user while he waits for the damn page to stop loading.

Never, ever venture out on the web without a content blocker.