Electricity prices have been rising steadily for years. And this is before any serious attempts to reduce carbon emissions, which is expensive. Source: http:/

Electricity prices have been rising steadily for years. And this is before any serious attempts to reduce carbon emissions, which is expensive. Source: http://www.eia.gov/todayinenergy/detail.cfm?id=20372 http://www.eia.gov/todayinenergy/detail.cfm?id=20372 For vertical farms that only use natural light, they only collect light equal to the building surface area (actually it's a bit worse on the sides). So, it would work fine for just the top story of the building plus a few crops on the sides.