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.

T5 fluorescent lighting has been around for a while now, but is not yet widely used in the manufacturing or warehouse sectors. Paul Smith has compared T5s with metal halide, and is interested in how T5s compare in terms of their total environmental impact.

As Paul writes, T5s strike faster, have good colour rendition, and a well designed T5 high bay luminaire, with 4 tubes, can be more efficient than a metal halide lamp, and have less lumen depreciation over its lifetime.

Both metal halide and T5 lamps contain mercury. T5 refers to the diameter of the tube, with T5 tubes being 5/8″ (16mm) in diamater. “Standard” fluorescent tubes are called T8s and are 8/8″ (25mm) in diameter. With a smaller diameter T5s use less glass and mercury than a T8 of comparable brightness.

Having said that, quite a few myths have developed around T5 lamps and as a result many people believe they are the best thing since sliced bread was invented. The luminous efficacy in lumens per watt of good T5 lamps approaches 105 lumens per watt, but this is only slightly better than the best T8 which is near 100 lumens per watt. Large wattage metal halides also have luminious efficiencies approaching 100 lumens per watt. However, like most things, just because a lamp is a T5 doesn’t mean its luminous efficacy is above 100 lumens per watt, there are many T5s on the market with an efficacy of only 80 lumens per watt.

The uptake of T5s has been much greater in the commercial building sector, particularly in offices, than in manufacturing and warehouses. The reason for this I believe is LEED (in Australia Greenstar) and other standards where building designers are seeking maximum efficiency in lighting. These drivers aren’t yet as strong in the manufacturing and warehouse sectors. Certainly in our work we mostly come across T5s in office buildings which are pursuing a high green star rating. And metal halide highbay light fittings are still much cheaper and much more readily available than T5 highbay fittings.

If you are designing a new commercial building it makes economic and environmental sense to use T5 lighting with high efficiency luminaires. The luminaire (light fitting) chosen is important too. The purpose of the luminaire is to direct the light coming out of the tube to where it is needed. Low efficiency luminaires are inefficient at doing this. To get the most out of T5 lighting you also need to be specifying high efficiency luminaires.  A big advantage T5 lights have over conventional T8 is their use of an electronic ballast, which extends lamp life, eliminates flicker, and reduces lumen depreciation.

For a commercial building retrofit the use of high efficiency replacement T8 tube in a double fluorescent luminaire and fitting of a specular reflector behind the tube to increase the efficiency of the luminaire enables the removal of one tube and halves energy use of the fitting. This is called delamping (more at our delamping webite). This provides larger energy and cost savings and is less expensive and more reliable than fitting T5 adaptors - devices than enable a T5 tube to be used in a T8 fitting. T5 tubes fitted with T8 adaptors have a lower luminous efficacy than the best T8 tube, so their use is not advised, not withstanding the marketing hype surrounding T5 adaptors.

In new warehouses in my opinion T5 high bay luminaires as described by Paul are far superior to metal halides. Paul outlines several reasons for this. The instant start of T5s is in many case perhaps the biggest advantage. When undertaking energy audits of warehouses I have usually see the high bay lights running all day, even though different sections of the warehouse will often be empty. This is very wasteful. Unfortunately HID lamps, such as metal halide, high pressure sodium, and the less efficient but inexpensive mercury vapour all take a long time to warm up, and therefore its not practical to switch them off in empty spaces. Forklift operators and staff just aren’t prepared to wait 10 or 15 minutes for the lights to warm up to full brightness.

T5 or T8 linear fluorescent lamps don’t have this problem. So they can be controlled by motion or occupancy sensors. In many cases the hours of operation of lights in warehouses could be reduced from 10 to 12 hours a day to less than 4 hours a day with the use of sensors and T5 high bay fittings. Lighting energy costs can easily be halved.

Another metal halide replacement is the induction lamp, which has the advantage of instant start as well, but can in some cases be retrofitted into the existing high bay fittings. Their luminous efficacy is also pretty good, they are easily dimmed (good where daylighting controls are installed), and prices are coming down. Induction lamps also have a very long lamp life, in the order of 50,000 hours (compared with 14,000 hours for a good metal halide and 20,000 hours for a good T5)

LED lighting is rapidly becoming more efficient, and we have tested LED fluorescent tube replacements achieving over 70 lumens per watt - which is a big improvement over the 40 to 50 lumens/watt we were seeing 12 to 18 months ago. If the luminous efficacy of white LED technology continues to improve this quickly, and prices start to drop, then we may find in five years time that LED is better than all other forms of lighting.

Climate scientists are clear when they say that large cuts in human caused greenhouse gas emissions are needed to slow climate change. But there are two popular assumptions in Australia, probably replicated in other countries, that are preventing these large cuts from happening.

The first assumption is that government should take most of the responsibility for greenhouse gas abatement. This is well summarised by Stephen Lunn, social affairs commentator, who writes in the Weekend Australian, 20 December 2008, that “Most… accept human activity is changing the climate. And most see it as the Government’s role to find a way forward”.

The second assumption is that cuts to greenhouse gas emissions are bad for the economy. The Rudd government has commited to reduce Australia’s emissions by only 5% by 2020. This is much lower than the 25% to 40% the United Nations Framework Convention and Climate Change said the world needed in Bali twelve months ago. The rationale is that larger cuts would be bad for the economy, especially if other countries don’t follow suit.

Furthermore the governments carbon pollution reduction scheme has reinforced the belief that it’s the government who should take full responsibility, by providing compensation to households whose energy costs may go up, and free emissions permits to many major polluters.

These two assumptions are probably commonly held by most people around the world.

Lets say Barak Obama takes a strong lead on climate change. He slashes US greenhouse gas emissions, and demonstrates that human development is possible without loss of American jobs or quality of life. He will have discredited the belief that cuts to greenhouse gas emissions are bad for the economy. And other governments are likely to follow. We may well just get the emissions reductions the scientists say are needed. Many people are hoping for this.

On the other hand if most individuals, families, and businesses around the world change their mindset and take responsibility for the emissions resulting from their decisions we are also pretty likely to get large cuts in greenhouse gas emissions.

But as long as our leaders believe cutting greenhouse gas emissions is bad for the economy, and as long as we continue to say it’s the government’s responsibility to do something, then dangerous climate change is inevitable.

I received yesterday a powerpoint about food security and climate change from Dr. Julie Cliff, a friend of mine who has worked in tropical medicine in Mozambique for the last 30 years. Her powerpoint had a dramatic image of cassava plants grown in laboratory conditions at different atmospheric concentrations of CO2 (shown below). Cassava is a staple crop whose tubers are consumed across southern and central Africa. The plants grown at higher concentrations of CO2 produced tubers with less than half of the useful food of the plants grown at lower CO2 concentration.

Yesterday I also met an economist who showed me some modelling that predicted the effect a $50 per tonne carbon price would have on the cost of employment across a range of sectors, such as manufacturing, banking and insurance, etc. Typically the cost was around $2,000 per employee – or in other words the modelling was predicting that business expenses would increase by $2,000 per employee if we had a carbon price of $50 a tonne.

These two viewpoints clearly show the apparent climate change challenge – one which shows that the response to climate change could be expensive, the other that not acting could have dire consequences for food security in southern and central Africa. This is the classic argument that I referred to in my first blog post – the climate change challenge is framed in a way that we lose economically if we act to limit greenhouse gas emissions now – but if we don’t act we will lose in the future.

So what is my climate positive take on this? More in my next posting – and comments welcome.