Multiple power supplies providing enhanced power efficiency

1. A method for supplying power in a computing system, comprising:

monitoring power consumption of the computing system;

supplying power to the computing system using only a first power supply over a first range of power consumption; and

supplying power to the computing system using a combination of the first power supply and a second power supply over a second range of power consumption;

wherein the first range is lower than the second range, wherein the first power supply provides greater efficiency than the combination of the first and second power supplies over the first range of power consumption, and wherein the combination of the first and second power supplies provides greater efficiency than the first power supply over the second range of power consumption; and

switching from the first power supply to the combination of the first and second power supplies in response to the power consumption increasing to a first power consumption setpoint; and

switching from the combination of the first and second power supplies to the first power supply in response to the power consumption decreasing to a second power consumption setpoint, wherein the first power consumption setpoint is greater than the second power consumption setpoint.

2. The method of claim 1 , wherein the combination of the first and second power supplies operate in a synchronous mode.

3. The method of claim 1 , wherein the first power consumption setpoint is greater than the power consumption corresponding to the cross-over efficiency between the first power supply and the combination of the first and second power supplies.

4. The method of claim 3 , wherein the second power consumption setpoint is less than the power consumption corresponding to the cross-over efficiency between the first power supply and the combination of the first and second power supplies.

5. The method of claim 4 , wherein the first and second power consumption setpoints are no more than 150 Watts from the power consumption at the cross-over efficiency.

6. The method of claim 1 , wherein the computer system includes a plurality of computer servers, and wherein the power consumption is that amount of power consumed by the plurality of computer servers.

7. The method of claim 6 , wherein the step of monitoring the power consumption of the computer system includes a management entity receiving power consumption data from each of the plurality of computer servers.

8. The method of claim 7 , wherein each of the plurality of computer servers includes a baseboard management controller that provides server power consumption data to the management entity.

9. The method of claim 1 , further comprising:

changing the number of computer servers in the computer system.

10. A computer program product including computer usable program code embodied on a non-transitory computer usable storage medium for managing the supply of power in a computer system, the computer program product including:

computer usable program code for monitoring power consumption of the computing system;

computer usable program code for instructing only a first power supply to supply power to the computing system over a first range of power consumption; and

computer usable program code for instructing a combination of the first power supply and a second power supply to supply power to the computing system over a second range of power consumption;

wherein the first range is lower than the second range, wherein the first power supply provides greater efficiency than the combination of the first and second power supplies over the first range of power consumption, and wherein the combination of the first and second power supplies provides greater efficiency than the first power supply over the second range of power consumption; and

computer usable program code for switching from the first power supply to the combination of the first and second power supplies in response to the power consumption reaching a first power consumption setpoint; and

computer usable program code for switching from the combination of the first and second power supplies to the first power supply in response to the power consumption reaching a second power consumption setpoint, wherein the first power consumption setpoint is greater than the second power consumption setpoint.

11. The computer program product of claim 10 , wherein the combination of the first and second power supplies operate in a synchronous mode.

12. The computer program product of claim 10 , wherein the first power consumption setpoint is greater than the power consumption corresponding to the cross-over efficiency between the first power supply and the combination of the first and second power supplies.

13. The computer program product of claim 12 , wherein the second power consumption setpoint is less than the power consumption corresponding to the cross-over efficiency between the first power supply and the combination of the first and second power supplies.

14. The computer program product of claim 13 , wherein the first and second power consumption setpoints are no more than 150 Watts from the power consumption at the cross-over efficiency.

15. The computer program product of claim 10 , wherein the computer system includes a plurality of computer servers, and wherein the power consumption is that amount of power consumed by the plurality of computer servers.

16. The computer program product of claim 15 , wherein the computer usable program code for monitoring the power consumption of the computer system includes computer usable program code for receiving power consumption data from each of the plurality of computer servers.

17. The computer program product of claim 16 , wherein each of the plurality of computer servers includes a baseboard management controller that provides server power consumption data to the management entity.

18. The computer program product of claim 10 , further comprising:

computer usable program code for detecting a change in the number of computer servers in the computer system.