Seagate has launched a ‘green' hard drive it says will allow system builders to slash disk power consumption without having to sacrifice performance.

The new SATA II Barracuda Low Power (LP) drive is physically identical to a standard 3.5 inch Barracuda desktop drive running at 7,200rpm, but special firmware slows the spin speed to a more economical 5,900rpm. Running more slowly reduces performance to some extent, but delivers less noise and less heat, which in turn allow system builders to use reduce the spec and cost on PC components such as fans and power supplies (PSUs).

However, the big pay-off is a reduction in drive power consumption of more than 40 percent. In an idle state the Barracuda LP uses 3 watts, or 5.6 watts while operating, which compares to the current Barracuda 7,200rpm's 5.0 watts in idle mode and 8.4 watts operating.

Seagate claims the drive also makes better trade-offs than rival ‘green' drive designs; Seagate figures showed Samsung's recently launched Eco Green using a whisker less power while operating - 5.5 watts to the Barracuda LP's 5.6 watts - but only at the cost of reducing spin speed and performance to 5,400rpm. Western Digital's Caviar Green used slightly more, 5.72 watts, although this is from a 5,400rpm design that first appeared almost two years ago.

The drive will be sold in capacities of 1.0TB, 1.5TB and 2.0TB, which means it will turn up initially in external USB and network-attached storage (NAS) drives, sectors that have become increasingly preoccupied with the issue of power consumption and heat dissipation. The benefits would be less pronounced for a desktop system in which the drive is only one component, but such drives clearly had a good future in the emerging niche of the low-power business PC, Seagate said.

"Growing demand for power-efficient computing systems is not just a data centre phenomenon as more builders of external storage devices, desktop PCs and home networking systems work to provide customers with products that combine power-efficiency with rock-solid performance," said Seagate vice president Joan Motsinger.

Seagate estimates that 95 percent of its 3.5 inch drive sales are for 7,200rpm drives, with higher-speed drives making up the remainder. The company would not be drawn on what sort of impression the arrival of the Barracuda LP might make on this market balance.

Pricing is $258 (approx £176) for the 2.0 terabyte model, with the 1.5 terabyte and 1.0 terabyte models costing $156 and $118 respectively.