In almost all commercial buildings, the Heating Ventilation & Air Conditioning (HVAC) system uses the largest percentage of power. Like lighting, the HVAC operates throughout business hours but its plant consumes much larger amounts of energy. Traditionally HVAC systems source heating from gas (oil in some cases) fired boilers, and cooling from electric chilled water or refrigerant plants. Reverse cycle package air conditioners produce heating and cooling via compressors within the unit. Most large HVAC systems are centrally controlled via a Building Management System (BMS), which activates the heating or cooling relative to the demand within the serviced area. This is controlled via a temperature set point, proportional bands and dead bands.

Shown below is a simple temperature control proportional–integral–derivative (PID) controller diagram. It shows a temperature set point and heating cooling proportional bands (PB) or percentage heating/cooling.

When the thermostat within the room reads a temperature below 21 degrees the percentage heating (PB) will begin to rise. When the proportional band reaches 35% the boiler is activated and will continue to heat until 0% PB (set point) is reached. This is unnecessary because as you can see, the temperature has only dropped 1°C from 21°C to 20°C, which is still comfortable for occupants. Also, heating should not continue until 0% PB as this will cause the room to overheat and subsequently call for cooling.

This type of control configuration creates a plant room scenario similar to that in the engine room of the Titanic! The boiler and chiller are constantly in operation in order to maintain the tightly controlled set point. Comfort levels within the serviced area are also compromised as occupants constantly feel surges of warm air followed by surges of cool air.

This problem can be easily averted by changing the control settings. Within the BMS, the boiler and chiller settings can be manipulated. If the heating percentage PB is brought out to 65% for instance, the boiler will not be activated until the room temperature reaches 19.3°C, which is still not cold for occupants. Also the boiler should be programmed to cut out at 25% PB as there will be a delay on the heated air getting to the thermostat. The room will still reach set point even though heating stops at 20.3°C. This will avoid the set point being unnecessarily exceeded and the cooling being activated. The same control fundamentals apply for packaged air conditioners.

The potential savings from the alteration of simple control bands are huge. The run times of both the boiler and chiller are significantly reduced, which shows up on your energy bills. At first occupants may complain that it is too hot or too cold. If this arises, have a thermostat close at hand to check that temperatures are within standard office comfort conditions (see “What is a comfortable office temperature” Bruce Rowse Dec ’09). Advise them on appropriate dress if they are experiencing discomfort. It may also help if they are advised as to why these modifications have been made and what has been achieved.

I have been involved in a lot of these control system alterations and I can safely say that it is the cheapest, easiest and fastest way to achieve significant electricity, gas, money and greenhouse gas savings from the your largest energy consumer, the HVAC system.

For a small business such as ours maintaining a healthy cash flow is a must. Cash comes into the business when invoices are paid. A recent survey showed that Australian businesses were on average now waiting 58 days for invoices to be paid. This means that for most businesses the cash that will come into the business in April is dependent on what the business invoices now in February. There is lag between when the work is done and when it is paid for. Failure to invoice enough in February could result in a business running out of cash in April. And when there is no cash, there is no business.

Climate change is similar. The carbon we put into the atmosphere now influences the climate well into the future. However rather that a time span of weeks or months, its decades. Todays carbon emissions will influence the climate for decades to come. So to get a stable climate in the future we need to cut greenhouse gas pollution NOW.

Many years ago a friend “temporarily” left the shell of a model T Ford in my front yard as he had no space to store it. Its still there. I haven’t asked my friend to take it away because it reminds me that some of the carbon that car generated over its lifetime is still in the atmosphere driving climate change.

Since climate change is like cash flow, if we want a stable climate as we grow older, and for the sake of our children and grandchildren, we need to be acting now.

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.

Controlled Plasma (CP) lighting technology is the latest of a number of emerging innovative lighting technologies that inadvertently help reduce GHG emission through energy efficiency. In fact its Melbourne inventor Graeme Huon (formerly and acoustics engineer) asserted that “If we were to replace 75 % of lights in homes with these globes in the next five years, we could save building one new power station”.

Cold cathode fluorescent lighting (or CCFL) has been around for a few years in the form of inductive lighting. However, what sets CP globes aside from the rest is that it is the first of its kind to be able to be used in homes as well as for commercial applications due to its affordability and design.

What is a CP globe? Graeme Huon explains: “It is a light source that utilises three existing filament-free light technologies; neon, cold cathode and high intensity discharge along with a new type of controller to regulate the way it works. That way you get flicker-free light and cool running temperatures. It only uses 5 watts, is dimmable and has a lifespan of 20 000 hours”. These together with good colour rendition and with very good light flux levels make it a real alternative to LED lamps and actually surpass CFL lamps in many ways.

To further simplify matters the GU10 globe is incorporated into a downlight fitting (similar in appearance to many existing 50 watt halogen fittings) and is fully sealed to keep out insulation, bugs and heat. This creative downlight is also so versatile that the same fitting can be used as a gimbal or flush type fitting or one can remove the globe with the controller and simply insert it into an existing downlight luminaire. It is fully compatible with existing wiring and comes in two versions; with a plug-in lead or as a quick connect system to be used by electricians. Due to their tri-phosphor coating they are available in warm white and cool white but in the future there may even be ‘party light colours’.

But are they a direct replacement for 50 watt halogen downlights? Well not quite. CP lights do have very good lux levels but they have a different directivity of light. CP lights don’t have a bright spot like halogens so they are not directly suited to long throw or spotlight applications. However, they are a possible alternative in some cases as long as one is aware that they provide slightly less but more uniform light. This means that for the same given area you will have to use more CP lights than you would use halogen downlights but since they only consume 5 watts each this is not a problem.

LED technology is developing at a rapid rate with better-brighter light levels and possible dimming capabilities in the near future. Nevertheless they are unable to match the low wattage for the same amount of light or the colour temperatures of CP lights. LED lights also run at a higher temperatures so large heat sinks need to be fitted to cool them. This doesn’t mean that LEDs are worse or can’t compare to the quality of CPs. It is more of a case of the LEDs being suitable for different applications and commercial use due to their own design features and price.

As for the CFL alternatives, they still use up to 11 watts and produce less light. Finally the cost of a CP unit cannot be matched by any of these two. They are rumoured to sell for under $60 per unit, which is less than half of an equivalent LED fitting and probably the same as a non-dimmable CFL fitting with lamp. CP light fittings will be distributed under the Kambrook name and are designed and produced by CP Envirotech.

(References: G Magazine April 2008; Green Lighting in Electrical Connections December 2008).

As part of an international effort to combat climate change, researchers worldwide are exploring new ways of reducing greenhouse gas emissions. One such method is Biochar, which takes organaic matter and burns it in a pyrolysis oven with no oxygen to produce a charcoal form and a renewable gas fuel by-product called Syngas. Carbon that would otherwise be released from the breakdown of organic matter is trapped in the biochar for hundreds of years and if returned to the ground has been shown to increase the fertility of soil.

Countries including Canada, Spain, Portugal and Denmark have already decided to go ahead with biochar as a way of reducing their carbon footprint. In Australia however, the federal government does not recognise biochar as a method of sequestering carbon, claiming the science is unproven. The Climate Change Minister, Penny Wong has stated that “soil carbon (including biochar) does not fit within the scope of the current Kyoto Protocol accounts, so is not included at this time in the Carbon Pollution Reduction Scheme”.

In NSW a renewable energy company called Best Energies has setup a pilot scheme to validate the technical feasibility of biochar. So far Scientists believe biochar has the potential to reduce Australia’s carbon emissions by 1 gigatonne, which is around to 20 percent of Australia’s total carbon emissions. This is a very significant reduction, however without recognising biochar within Australia’s future emissions trading scheme there is little financial incentive for the commercial sector to invest in this technology.

The government is already spending millions in carbon capture research in the coal sector, but compared to biochar is a technology not yet in existence. The CSIRO are also researching the potential merits of biochar and its affect in different soil types, however are dependent on overseas funding. Biochar is an exciting prospect and with gaining momentum worldwide it is questionable as to why the Australian government is taking a sceptical stance. Hopefully new light on the properties of biochar will be in favour of Australian conditions and government support turned around. With increasing drought and a large agricultural sector in Australia the potential benefits of biochar should not be overlooked.

What do you think?

For more information have a read of the CSIRO biochar fact sheet at, http://www.csiro.au/resources/Biochar-Factsheet.html

A recent video report is also available from The ABC’s 7:30 Report website, http://www.abc.net.au/7.30/