ok lets do some math
320exahash network today
190thash $3639 and 5.2kw per asic
=1684210 asics
=$6112000000 hardware / 105000 blocks* / 6.25btc
=$9313.52 per btc hardware cost
..
1684210 asics x 5.2kwh
=8757895 kw/h x $0.04
=$350315.7894736842 per hour / 6blocks** / 6.25
=$9341.75 per btc electric
total = $18,655.27 hardware+electric per btc for todays hashrate of 320exa
*2 years of blocks
** blocks per hour (even if you multiplied to the fortnight then divided by 2016 = same $ amount)
It doesn't take into account difficulty change, which may be very volatile.