Energy Use

  IT Energy Use - An Overview

IT Power Demand in Context 

- IT accounts for 2-4% of global energy demand
- Equal to the global aviation industry in carbon emissions
- Total ICT emissions 830 MtCO2e in 2007 (Global total emissions about 40GtCO2e – 2002)
Source: Smart 2020: Enabling the low carbon economy in the information age. The Climate Group on behalf of the Global eSustainability Initiative (GeSI)

We need to reduce the amount of CO2 we are pumping into the atmosphere and energy use is a big contributor.<!-- For Search Engine Spiders -->

One of the best ways to reduce PC energy use for larger companies is to use a centralised computer energy management solution. Consequent cost reductions go straight to the bottom line with the added benefit of a reduced carbon footprint.

The IT industry has tended to focus on data centre energy efficiency and not on PCs (computer and monitor). However PCs make up 40% of an organisation’s total ICT energy bill (diagram below). In comparison servers use 23% of energy.

The electricity cost of a typical PC (including a standard 17” flat screen monitor) will be about $111/year if it is always left on (738.60kWh of electricity per year at 0.15¢/kWh). This can really add up with a large number of PCs.


In addition to financial costs there is the environmental cost of carbon emissions. Electricity generation in New Zealand currently creates 0.195kg of CO2 per kWh. Each PC could contribute 144kg of CO2 per year if it’s always on.
PCs affect energy use in other ways. In a typical office the PCs, monitors and general office equipment make up 25% of total energy used whereas air-conditioning uses about 50%.


Air-conditioning units have to counterbalance the heating effect of PCs so effective PC energy management will reduce air-conditioner energy use.

Almost half of all employees who use computers at work typically do not power them down at the end of the working day - read report

Typical Savings

On average you will save NZ$33 per desktop per year in electricity costs if you use 1E NightWatchman to centrally control the power states of your desktop fleet.

For every 1000 PC's this equates to approximately the following savings per year

  • $32,000 in electricity costs

equal to

  • 42 Tonnes of CO2 emissions
  • Taking 12 cars off the road
  • Carbon sequestered by 532 pine trees seedlings grown for 5 years
  • Carbon sequestered annually by 1229.20 m2 of pine forests
  • Carbon stored in 662.20 m2 of New Zealand native forest preserved from deforestation

This is not low hanging fruit, this is fuit laying on the ground!

The Top 100 Companies, inluding large Government departments in New Zelaand have about 270,000 PC's (please note that this does not include laptops, thin-clients or hand held devices).

If these enterprises implemented the 1E energy management solution they could save the following per year:

  • $8,819,604 in electricity costs (yes that is nearly 9 million dollars)

equal to

  • 11,465 Tonnes of CO2 emissions
  • Taking 3,276 cars off the road
  • Carbon sequestered by 145,223.3 pine trees seedlings grown for 5 years
  • Carbon sequestered annually by 335,542.3 m2 of pine forests  
  • Carbon stored in 180,764.8 m2 of New Zealand native forest preserved from deforestation
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