To calculate the math more correctly, a 1W smart plug is contributing $0.09/month to the $400 electrical bill quoted. This is a stellar example of a micro-optimization, in programming terms.
Focusing on big spenders like "anything with a pump" and "anything that generates heat" would contribute significantly to reductions.
I once upgraded video cards, reducing my computer's power draw by 180W and lowering my electric bill accordingly. This was back in the early days of CFLs (they were terrible) so it may not seem like much, but it was on 24/7 and that was the power at idle. I think it worked out to something like $10/month of savings, which was quite noticeable for my total bill of $50 or so.
Focusing on big spenders like "anything with a pump" and "anything that generates heat" would contribute significantly to reductions.
I once upgraded video cards, reducing my computer's power draw by 180W and lowering my electric bill accordingly. This was back in the early days of CFLs (they were terrible) so it may not seem like much, but it was on 24/7 and that was the power at idle. I think it worked out to something like $10/month of savings, which was quite noticeable for my total bill of $50 or so.