I have now confirmed the idle-power usage of the new OWC Mercury Extreme Pro 6G SSD directly with OWC at 150 milliwatts, and I’m waiting for confirmation that the active power draw might actually be somewhat lower— final testing as-built will establish more accurate figures for both idle and active power usage.
The higher power draw over the 3G model is due to the use of Synchronous NAND Flash (the memory chips). Any design for high performance using these chips is going to have similar power draw. Other designs with asynchronous chips are possible, but these will be lower performance.
Comparing power usage — 3G vs 6G SSD
Power consumption at idle of the 6G SSD is higher than the 3G SSD, but still well below an idle but spinning hard drive. And an SSD does not need to be spun up or spun down.
Short story: I don’t consider power usage of the OWC 6G SSD to be an issue.
OWC 240GB 3G SSD
Active: 2200mW (2.2W) typical, up to 2500mW (2.5W)
Inactive (DIPM): 90mW (.09W) Typical
OWC 240GB 6G SSD
Active: 3700mW (3.7W) expected maximum draw
Inactive (DIPM): less than 150 mW (0.15W)
Seagate 750GB 7200 rpm laptop hard drive
Seek power: 2.5W
Read power: 2.1W
Write power: 2.3W
Idle mode, performance: 1.5W
Idle mode, active: 0.95W
Idle mode, low power: 0.7W
Standby mode: 0.15 watts
Sleep mode: 0.15 watts