If you are looking for a freeware to estimate the power consumption of your computer then you can try out Joulemeter. Joulemeter is a free application from Microsoft which can be used to measure the energy usage. Joulemeter is a software based mechanism to measure the energy usage of virtual machines (VMs), servers, desktops, laptops and even individual softwares running on a computer.

Joulemeter estimates the energy usage of a VM, computer, or software by measuring the hardware resources like CPU, disk, memory, screen etc being used and converting the resource usage to actual power usage based on automatically learned realistic power models. If you are concerned with the eco-sytem you can use Joulemeter to estimate the energy usage and take necessary steps to reduce energy usage. Joulemeter can be used for gaining visibility into energy use and for making several power management and provisioning decisions in data centers, client computing and software design.

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