I think you need to go the other way start at what a US based 20 AMP 120V power plug could supply and work backwards using the 1 THash box.
15 AMPs * 120V == 1800 watts, 80% eff would give 1,440 watts available.
~695MH / Watt
1440W is a good assumption! This number matches almost exactly my OP which estimates the Jalapeno at 700 Mh/Joule by using 2 USB plugs for power.
This 700 Mh/Joule number makes so much sense that it has become my best bet as to what the SC product line will produce.
700 Mh/Joule is even doable at merely 45nm per my OP.
- Jalapeno SC: 5W via 2 USB plugs, 3.5 Ghash/s -> 700 Mhash/J
- Single SC: 57W, 40 Ghash/s -> 700 Mhash/J
- Mini Rig SC: 1440W, 1 Thash/s -> 700 Mhash/J