Even without considering the additional sustainability benefits to be achieved from the scale and efficiency of commercial data centres, or the proactive monitoring of energy usage, private data centres can potentially quadruple utilisation to 80 per cent with only a 50 per cent increase in power consumption.

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Google and Facebook operate at a Power Usage Efficiency (PUE) of 1.02-1.2, while typical enterprise datacenters operate at 1.6 or above.

FORBES: How The Cloud Can Unify The World: OpenStack And Nebula

The eco-rating system assesses 15 specific criteria drawn from five general categories of sustainability attributes - attributes include the usage of environmentally preferable materials, minimization of hazardous substances, energy efficiency, responsible end-of-life treatment and environmentally-responsible manufacturing.

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OPower leverages government data on energy usage, weather, and the energy efficiency of appliances to help customers get personalized advice on how to save on their energy bills.

WHITEHOUSE: Open Government Data Spurs Entrepreneurship and Jobs

It's because of appliance and efficiency standards that we've been able to keep our energy usage relatively flat, and considering California is on average a warmer state, that's pretty amazing.

FORBES: Obama's High-Tech Energy Pick

Forgitit households are monitored for energy usage and their efficiency is calculated based upon different variables such as the square footage of the home, and all the data is put toward a greater energy consumption metric.

FORBES: Set it and Forget it: Energy Monitoring Startup Forgitit Launches