Tackling Hard to Reach Distributed Energy Losses in the Non-Intensive Energy Use Sector – Power Management in PCs 

With the new Carbon Reduction Commitment (CRC) regulations, many businesses are about to face the realities of carbon budgeting for the first time.  Organisations will be required to buy allowances to cover their CO₂ emissions; top performers will receive financial rewards; and poor performers will be penalised. 

 The CRC uses electricity consumption as a means for determining which organisations fall under the new regulations, and covers all organisations with an electricity consumption of greater than 6,000 MWH per year (equivalent to emissions of approximately 1,280 tonnes CO₂ per year from electricity use). Organisations must purchase allowances to cover all of their CO₂ emissions with the exception of transport. 

The CRC will incentivise energy efficiency and greenhouse gas emissions reduction in the non-energy intensive sector of business and industry.   As well as driving supply side measures to reduce the carbon intensity of energy consumed, the CRC will also provide big incentives for demand side energy efficiency.  Once quick wins have been identified, attention will become more and more focused on harder to reach energy losses.  These include energy losses distributed across organisations due to the organisations physical infrastructure, and also the way it uses energy consuming devices.

 Invisible Energy Losses 

Whilst most people are familiar with measures such as smart lighting systems using low energy bulbs and motion sensitive switching, a ubiquitous energy demand across all businesses is the personal computer.   A typical PC will use in the order of 90 watts when active (approximately 50 watts for the base unit, and 40 watts for a typical LCD screen); and three to four watts when ‘asleep’. 

With up to 25% of a modern office’s electricity demand being used to feed an ever-growing IT infrastructure, and PCs and monitors accounting for nearly 40% of IT energy demand, PC power management is a key aspect of facilities energy management. Recent research [1]shows that across the industrialised economies, major and unnecessary energy losses occur simply through people failing to power down their PCs when they leave work. 

In the UK, it is estimated £300 million per year in energy costs are wasted, and 1.3 million tonnes CO₂ emitted as a result.  In the US, where research shows over 50% of PCs are left on overnight, the figures are even higher - $2.8 billion and 20 million tonnes of CO₂ per year – the equivalent of the whole of Estonia’s CO₂ emissions. 

It is also the case that whilst PCs do allow low power settings to be used, there are many situations, especially in a networked environment, where processes running on the computer will prevent the in-built low power settings from taking effect.  This can have a dramatic effect on energy use that is invisible to the user.  T

he monitor may have gone into standby mode, and the PC may appear to be idle, but our own operational testing here at 1E, shows that  on any given day an average of over 50% of an organisations computers would fail to go to sleep, and over time this happened to over 90% of the machines. This means that the actual power use of ‘sleeping’ computers is over 7.5 times the expected ‘sleeping’ power demand. 

Sleepless PCs  

There are three things that prevent a computer from switching to sleep mode. These are:

·        user activity (keyboard input or mouse movement);

·        CPU Activity above a threshold (by default 20% overall CPU utilisation);

·        a process actively requesting that the computer remains awake.Further detailed analysis showed that all of these things were happening on various computers and at various times of day and night for a variety of reasons:

  some computers had faulty mice which caused pointer drift, making the operating system think that a user was continually moving the mouse;

others had installed utility software that attempted to actually prevent the computer from sleeping by periodically sending a spurious key press event;some applications would periodically run internal maintenance tasks causing spikes in CPU activity, but doing no useful work;

some applications would raise a ‘System required’ flag preventing the computer from sleeping. Sometimes this was where users had left applications open that were playing music, or in ‘presentation’ mode.  A lot of the time this was because the application had a file open across the network. 

Energy Management Solutions 

PCs refusing to sleep, and the subsequent waste of energy, is difficult to manage across a network using a computer's internal energy management settings.
However, a very effective energy management tool, NightWatchman, has been developed by 1E that addresses these problems, and also allows network administrators to automatically wake up machines for eg network maintenance and corporate software upgrades, and power them down afterwards. Using this energy management tool on an organisations network has been demonstrated to save on average 200 kg of CO₂ emissions per PC per year, and generate £26 per PC per year in energy savings.  

The NightWatchman tool has been extensively used in many organisations over the last eight years.  With over 4.5 million users globally, it represents a tried and tested energy management system that attacks a particularly hard to reach distributed energy loss.  CO₂ emissions savings of over 900,000 tonnes, and energy savings of over £110 million are made each year by NightWatchman users across the world.  This type of energy management tool can be a very powerful weapon in an environmental or facilities manager’s armoury.  An organisation such as a large consultancy with 4,000 employees would be able to make CO₂ emissions savings of over 800 tonnes and over £100,000 per year in energy savings.  A large corporation with 50,000 employees could save 10,000 tonnes of CO₂ and over £1.3 million per year in energy costs. 

Implications for the CRC

 By looking at IT operations and energy use, proven energy management tools such as NightWatchman demonstrate that the CRC target of 4 million tonnes of CO₂ emissions reduced by 2020 is readily achievable.  With the reward and penalty system under the CRC, organisations will be continually pushed to improve their emissions reduction performance.  Energy management solutions such as NightWatchman turn a very hard to reach energy loss into an easily achievable and quantifiable efficiency gain.  This type of solution can help organisations maintain leadership positions in CRC league tables, so as well as very significant energy cost savings, financial rewards under the CRC can be ploughed back into the organisation, making a very clear business case for effective environmental management.