The Apple Thunderbolt Display Review

Power Consumption

Unsurprisingly, power consumption hasn't changed much in the past year. The Thunderbolt Display draws a bit less at its dimmest setting (likely just panel efficiency variance) and draws a bit more at max brightness:

While powering a 15-inch MacBook Pro and reading data from an attached Pegasus R6 (copying to a local SSD at around 200MB/s) I measured total power consumption for the display (max brightness) at 179.6W. That number could go up if the battery in the MBP was near empty and thus being charged at a higher rate.