carbonetix

Archive for the ‘Computers and office equipment’ Category

Virtual desktops provides large computer energy savings and are becoming easier to deploy. Great for schools and offices!

Wednesday, July 22nd, 2009

Virtual desktops provides large computer energy savings and are becoming easier to deploy. Great for schools, universities and offices!

Most of the time only a small fraction of a computer’s power is being used. If you took a office or school with say 100 PCs, with an average load of say 15%, in effect 85 of the PCs would be redundant if it was possible to take advantage of the full power of 15 PCs across 100 work stations.

By employing “thin client” or “virtual desktops” this is made possible. With virtual desktops one PC “box” can then be used to power multiple workstations. This leads to very large energy savings. Additionally by reducing the number of “boxes” there is a resource saving. Maintenance costs are reduced and total lifecycle cost is lower.

There are some impressive examples of where this technology is now being used. Ncomputing is a vendor of virtual desktops, with 180,000 units deployed in schools in Macedonia. Canon in Thailand are using virtual PCs, as is DHL in Peru. In the USA virtual desktops are being used in schools in California and Wisconsin. In Australia its customers include schools such as Wondonga South Primary (Vic), Brighton Public School (SA), MacGregor State High (Qld).

In Australia Gold Creek and Parlmerston district schools in the ACT are using thing client computers supplied by Dycom. RMIT University in Melbourne is also using thin clients.

Take up of thin clients could however be much stronger. Victoria’s Department of Education and Early Childhood Development has reported weak demand from schools inquiring about the National Secondary School Computer Fund which is part of the Commonwealth Government’s Digital Education Revolution.

The flexibility of notebook computers is certainly an advantage over thin clients. However for total minimum power use and minimum life cycle cost and resource use its hard to beat a thin client or virtual desktop system. Thin clients should certainly be seriously considered by anyone involved in computer purchasing and network administration.

Voltage reduction could save 15 million tonnes of greenhouse gas – part 2

Monday, July 13th, 2009

A few months ago I wrote a blog posting about how tighter regulation of electricity supply voltages could save Australia 15 million tonnes of greenhouse gas a year.

However a comment on that posting suggested that voltage reduction may not result in any useful savings.

Below I report on the results of an experiment we undertook to identify how much power can be saved, if any, by operating equipment at a lower voltage.

We measured a variety of single phase loads at different voltages. A variable transformer was used to vary the voltage. A German made Power Tech plus plug in power meter was used to measure voltage, current, power and power factor at the different loads. Loads experimented with included typical single phase lights, computer equipment and a fan.

experimental set up to measure power draw at different voltages of a range of single phase loads

experimental set up to measure power draw at different voltages of a range of single phase loads

The experimental set up is shown above. Below is a graph showing the results of the testing.

graph of power draw vs voltage for a variety of single phase loads

graph of power draw vs voltage for a variety of single phase loads

This graph clearly shows that for common lighting loads power consumption decreases with decreased voltage

  • Incandescent lamp (resistive load)
  • T8 fluorescent (inductive load)
  • T5 fluorescent (electronic ballast)

The reduction in power consumption with the T5 fluorescent (with an electronic ballast) was unexpected.

The fan, with a single phase (shaded pole?) motor, also used less power with lower voltage, interestingly the power factor improved as voltage was lowered, with the power factor the highest at 220 volts.

The PC computer and monitor both showed lowest power consumption at 230 and 240 volts, but power consumption generally did not decrease with voltage. Power factor improved a little at lower voltages.

This experiment shows that for a variety of loads power consumption is in fact less at lower voltage.

For heating or cooling loads equipment may need to run longer when at lowered voltage to reduce the same amount of heating or cooling, with no net energy savings.

Three phase synchronous motors are unlikely to use any more or less power (a theoretical assertion, we don’t have the equipment to test), having the motors run at 230 volts rather than 240 or 250 volts however is unlikely to cause motor damage due to excess current as the voltage difference is only small.

But with lighting and many single phase motors power consumption drops with lowered voltage.

My back of the envelope calculations still come up with a saving of around 15 million tonnes of greenhouse gas if voltages were closer to the 230 volt standard rather than being at 240 to 250 volts.

If high voltage drops in distribution were a problem additional network infrastructure could be used to deliver a more consistent voltage across the network. 2009 is the year of the “smart grid.” A smart grid could mean multitap transformers that can be changed on the fly to deliver a more consistent 230 volts across the whole electrical network.

Seven examples of Climate Positive Action for World Environment Day

Friday, June 5th, 2009

Once you start listening for climate positive stories or examples you’ll find lots to be inspired by. I’ve heard quite a few of them over the last 18 days. Here are seven quick examples of organisations that have saved money and greenhouse gas by cutting their use of energy.

  1. University of New South Wales mail centre – Fuji Xerox helped them achieve a 23% reduction with new copiers and printers / consolidation of machines.
  2. Airbus – the new A380 uses 40% less fuel per passenger km than aircraft of 25 years ago.
  3. Google server rooms – use less than half the energy of a typical server room of the same capacity.
  4. Dell computers saved over USD$1 million by improving the computer switch off practices of its staff.
  5. The leading Sustainability Street (a program run by Vox Bandicoot) – cut greenhouse emissions by 49%.
  6. Gaden’s Lawyers cut energy consumption by 20% through behaviour change. No capital cost.
  7. Logistics company Linfox is aiming to cut its emissions by 15% by 2010. A driver training program is already making a significant contribution to the achievement of this target.

Now that’s climate positive! How much could you save?

Overnight energy audit saves $50,000

Wednesday, March 4th, 2009

We assume so much in life, both personally and at work. Our assumptions and reality aren’t always the same. An occasional “reality check” can be very valuable. I wonder what expensive assumptions our organisations might harbour?

One of our clients, a medium size organisation somewhere in Australia, discovered in a very easy way that they were unnecessarily using $50,000 extra electricity each year.

It only took an overnight audit to discover this fantastic wastage. It was done by their staff as participants in our Greenhouse Gossip program

Most staff would shut down their computers when leaving work. No one was there to see that many of the computers were turning themselves back on around 8pm! Really, who would expect that?

After their audit, the staff came back the next day, to speak to the staff members whose computers were on. They discussed this and discovered the problem. By speaking to staff in other buildings in their organisation, and the ICT people, they discovered it was across the organisation.

The problem is now solved and they have an additional $50,000 to use each year from that one building (plus other savings identified and implemented in the program).

This is the kind of benefit that a structured, inquiring program can deliver.

Local climate extremes demand concerted positive action

Tuesday, February 10th, 2009

Black Saturday 7 February 2009: Melbourne’s temperature reached 46.4 degrees (116.5 deg F), fanned by strong hot winds 400 bushfires across the state killed over 170 people and destroyed 700 homes. And the dams supplying the state with water are at record lows.

If letters to the editor in the newspaper are any indication, many people are making the link between the terrible events of 7 February and climate change.

Fifteen years ago – on 21 March 1994 in Rio de Janeiro the United Nations Framework Convention on Climate Change (UNFCCC) came into existence. This document states that “The Parties should take precautionary measures to anticipate, prevent or minimize the causes of climate change and mitigate its adverse effects. Where there are threats of serious or irreversible damage, lack of full scientific certainty should not be used as a reason for postponing such measures.”

Australia’s parliament ratified the convention in 1992 – before it came into force. The USA ratified it in 1992. China ratified it in 1993. 192 countries around the world have ratified the UNFCCC.

Yet fifteen years on global carbon emissions have ballooned. Clearly the parties have NOT undertaken precautionary measures to prevent of minimise the causes of climate change and mitigate its adverse effects.

Based on my understanding of climate change science had there been concerted action to take precautionary measures fifteen years ago Victoria may have still experienced Black Saturday, although perhaps it might not have been quite as bad. This is because of the tremendous inertia in climatic systems. I’d be happy to stand corrected on this by someone suitably qualified.

However if we had managed to cut global carbon emissions from 1994 on I believe that the likely 50 degree temperatures that I have a feeling Victoria may be experiencing in the next twenty or thirty years probably could have been avoided. And that we may well have in our vocabulary then a complete set of Black days – a Black Sunday, a Black Monday, a Black Tuesday, a Black Wednesday, a Black Thursday, a Black Saturday and a Black Sunday.

Unfortunately based on what I read of the science of climate change this full suite of Black days could now well be locked in because of the great inertia of our climatic systems. However if we do manage to greatly cut emissions now we may avoid even worse weather.

Why, in 2009, are atmospheric concentrations of greenhouse gases still on the rise? I believe primarily because of fear of the economic costs that may arise if resources were put into cutting carbon pollution. Fear fanned by fossil fuel dependent industries.

Yet ever since former World Bank chief economist Nicolas Stern published the Stern Review of Climate Change in 2006 its been credibly shown that the future economic consequences of inaction far outweigh the economic costs of acting now to prevent dangerous climate change.

Whoever you are that is reading this – if you are shocked by the events of Black Saturday -  let me put it to you that you should consider cutting your carbon emissions to lessen the number of future black Tuesdays. Don’t just say this is the government’s problem and leave it at that. You see most governments around the world are not doing enough to drive the sorts of carbon cuts we need. The Australian federal government is an example of this – the 5% carbon reduction target by 2020 is laughable given what the science is saying.

So it is up to all of us to do something – both at home and also at work. Don’t just bitch and moan about how the government isn’t doing enough. Do something yourself. Take whatever assistance you can get from your government - but don’t stop at that - go beyond that. People of the world – unite to cut our carbon emissions – hopefully our government’s will one day start to genuinely lead instead of just continuing to play the prisoner’s dilemma.  (That is saying they recognise there is a problem, but aren’t willing to act unless other countries act because acting alone would be bad for the economy and that acting along wouldn’t reduce carbon emissions sufficiently to actually make much of a difference). And if you live in Victoria, make a fire plan.

And let me also suggest that choosing to act may not be of that much economic cost now, that in fact if you are particularly wasteful in your use of fossil fuel sourced energy that you may still be in front financially by cutting your carbon pollution - even after you’ve spend some of your savings to buy 100% greenpower.  And that choosing to act now may well be of great benefit to you and your family in the future.

At home get a smaller car. Then substitute a drive with a phone call, a walk or a cycle. Switch off stuff not in use - at the wall. Insulate. Get rid of those horribly wasteful halogen downlights.

At work do an energy audit, or get one done, and act on it. Delamp. Optimise your cooling and heating. Turn off stuff not in use - at the wall. Get energy efficient computers and equipment.

At home and work buy 100% certified green power, or get solar panels (make sure you aren’t selling the carbon savings in exchange for a discount from the supplier).

Climate change demands a vigorous, positive response - the more of us who do this, the greater the likelihood of climate stability in the future.