As we've discussed previously, an SSD that draws 25 W is no power-saver on its own. However, when you add up the number of 2.5" SAS-based disks spinning at 10,000 RPM it'd take to match the performance of a drive like the P320h, the savings are significant.
Just like the SSD 910 we reviewed previously, Micron's RealSSD P320h is also rated at 25 W. The P320h does have a lower idle power draw, but considering the environments these drives are intended to serve, they won't be sitting idle very long.
The P320h butts right up against its power ceiling subjected to both sequential and random operations. That's good news because any extra consumption would translate into more heat. The P320h also requires 1.5 m/s of airflow, which allows it to operate at up to 50 degrees C. As with most PCIe cards rated at 25 W, normal server airflow is enough to keep it cool. However if your rack-mounted machines suffer from restricted ventilation, the P320h will get very hot, very fast.