Hi,I don't actually have an answer for you, but a question..We too are considering Hydro-sil, except we have forced hot air..After numerous checks with the BBB (which they are so so) and numerouse searches, we think this is the way to go..I am just curious about your electric bill. You stated 493.79 is that just for the month of December?? Also do you know anyone else who has gotten them?? Thanks and sorry to answer your question with a question..and if I find out any info on the savings I will let you know. Thanks Cheryl