Earlier quoted context omitted.
Let's assume that you would need 1000 machines to have as much throughput as 4000 people. WAG, but I'd wager that each of those machines would cost $500k. That means 100 million in immediate outlays. WAG 2: fuel/electricity/maintenance is $200/month, and you need a team of 20 engineers to watch over them at $10k/engineer/month. So recurring costs come to $400k. Which brings us to: 100M/1.3M = 77 months, or between 6…
This article: http://money.cnn.com/2011/11/09/smallbusiness/kiva_robots/in... says that 1000 robots costs $15-20 million, not the $500 million that 500k a piece would run. Also what is there to indicate such a hefty need for engineering oversight? 20 engineers constantly overseeing the machines sounds like they are either constantly breaking down, or need a significant amount of custom programming per unit as upkeep,…
An 180 lb person speed walking at 5 mph burns 650 Calories/hr. That's 80¢/shift in electricity.
But that's not the big savings. Humans need lights and air-conditioning – robots don't. http://www.youtube.com/watch?v=Fdd6sQ8Cbe0#t=5m40s