We have recently been working on a site with a centralised steam system. It has two natural gas fired boilers supplying steam to a number of plant rooms, with the steam used to generate domestic hot water and heating hot water amongst other things. So how efficient is this system? And are there alternatives to steam that use less energy?

The short answer is that the steam system is very inefficient. It could be replaced with a decentralised system using a combination of hot water boilers and, where process steam is needed, small steam boilers. This would halve energy use.

Centralised steam systems have losses designed into them that cannot be avoided. Firstly the boiler blow down results in energy wastage. Then, because of the high pipe temperatures, any heat losses from uninsulated pipe is higher than it would be if the temperature was lower. Failed steam traps waste energy by not using the steam before it turns to condensate. And leaks and steam vents waste valuable condensate. Finally because still steam will eventually condense and needs to be taken away by a steam trap then reheated the standby losses are high. All these losses add up to large inefficiencies.

Steam is a old technology, and its use should be limited to only where absolutely necessary. Using steam to generate hot water is very inefficient. Much more efficient would be to use a high efficiency condensing flue hot water boiler, a direct exchange boiler, which will use half the energy to generate the same benefit. Heat pumps could also be considered if a water temperature of no more than 60 degrees Celcius was required.

If you’ve ever thought about putting a wind turbine on your suburban house, but then started to research it, you’ll know that wind turbines don’t work too well in cities and the suburbs. Even if its windy, turbulence means that unless you can get your turbine very high – three times as high as anything within a few hundred meters (including your house), the turbine simply won’t generate much wind. I recently saw a study of 30 odd urban wind turbine installations in the UK which showed very poor performance.

It looks as though this problem may have been overcome with a radical new design. Humdinger, a US company, have come up with a wind generator that makes electricity from the vibrations of a belt flapping in the wind. Its a great sounding idea. From the looks of their website the product isn’t yet in commercial production – so don’t get too excited yet. But I like the thinking behind the idea – instead of trying to make something with blades and a rotary motion – make it linear, and in theory it may be more reliable and robust than a rotary device where there is lots of turbulence. www.humdingerwind.com

Yesterday I attended the public consultation in Melbourne about accounting for and measuring voluntary greenhouse gas savings. The consultation was run by the Offsets Policy Team from the Department of Climate Change.  

It was good to be consulted and heard, and made me feel a little less disenfranchised by the CPRS.

Four or five years ago I attended a number of state government consultations on climate change. There was always strong disagreement and a lack of consensus. Yesterdays workshop was doubly satisfying for not only feeling that my opinions were being heard, but to also see that pretty well everyone else who attended was expressing the same view point. Many individuals and small businesses want to make a contribution to reducing greenhouse gas emissions. And we want our contribution to be a real, recognizable contribution that actually reduces carbon emissions and is additional to that which would be achieved by the CPRS.

It was reassuring to be able to ask questions like “what is the definition of a small business under the CPRS” and learn that this same question had been asked in similar workshops around the country.

Hopefully the workshops will help the government make changes such that voluntary carbon ababement by businesses and organisations not liable under the CPRS is recognised. In a way that the business doesn’t have to “pay twice” to get their carbon abatement recognised. And that withdraws the carbon voluntarily saved from the CPRS.

Starting today, public workshops are being held by the government to get public opionion and advice about how voluntary climate change action can be taken into account when setting emission caps for the Carbon Pollution Reduction Scheme (CPRS).

Workshops are being held on the following dates:
Perth
11 June 2009 9:00 am – 12:00 pm
Rydges Hotel Perth Corner Hay & King Street, Perth
Adelaide
12 June 2009 9:00 am – 12:00 pm
Mercure Grosvenor Hotel 125 North Terrace, Adelaide
Brisbane
30 June 2009 9:00 am – 12:00 pm
Chifley at Lennons 66 Queen Street Mall, Brisbane
Sydney
16 June 2009 9:00 am – 12:00 pm
Wesley Conference Centre 220 Pitt Street, Sydney
Melbourne
24 June 2009 9:00 am – 12:00 pm
Rydges on Swanston 701 Swanston Street Carlton, Melbourne

To attend register your interest at:
http://www.climatechange.gov.au/emissionstrading/householdassistance/index.html.

Voluntary action isn’t recognised under the proposed CPRS unless you pay to have the carbon retired into the Carbon Trust. In other words you pay twice – you pay to actually cut your carbon emissions (eg upgrading your office lighting by installing reflectors. Then, if you want the carbon you’ve saved to be “retired” so it can’t be traded by one of the large companies participating in the CPRS you have to pay again to lock it up in the Carbon Trust.

This is a tremendous disincentive for voluntary action. So have your say at these workshops.

In October last year CarbonetiX started an independent evaluation of LED lights as a substitute for fluorescent lighting. LEDs, standing for light-emitting diodes, have previously been commonly used for other purposes such as for low energy indicator lights on household equipment, but have not yet been widely used for general commercial lighting.

The evaluation is being undertaken by CarbonetiX in partnership with the Sustainability Fund, managed by Sustainability Victoria, and with the support of Frankston City Council. Eight months on and the trial is now nearing conclusion.

176 fluorescent tubes were replaced with solid state LED lamps in the Mahogany Neighbourhood Community Centre in the City of Frankston.  Users of the facility were surveyed before and after the upgrade and noted either no change or an improvement in the lighting. An illumination assessment showed that illumination levels after the upgrade were around the same as before. Yet power consumption has dropped from over 40 watts per lamp down to 18 watts.

The trial has involved firstly a desk-top evaluation of LED products, then selection of lamps from those six manufacturers who appeared to have the best products. These were then tested by CarbonetiX for light output and power consumption. The best performing lamp was then sent to a NATA (National Association of Testing Authorities) certified laboratory for photometric testing.

It was disappointing to have the only Australian lamp fail during our in-house testing. However the overall testing result was  surprisingly good: the useful light provided by the best lamp in a standard office troffer was similar to that of a used halo-phosphor tube, whereas our earlier program of testing indicated the LEDs were just not bright enough to be used as a fluorescent substitute.

This means that where a building is currently lit by halo-phosphor lamps, which are still quite common fluorescent tubes, and where the illumination levels exceed those specified in AS1680, that the best LED tube could be used as a fluorescent substitute. 

Another concern was the reliability of the product. Barney Mezey, our energy auditor who ran with the project, was concerned about the headache that failure of the lamps would cause. Fortunately all of the lamps are still working three months after they were installed. Obviously this is nowhere near long enough to establish whether or not the lamps will operate for 50,000 hours or not as claimed by the manufacturer. But it is a good start..

LEDs are still expensive, with CarbonetiX estimating a twelve year return on investment. But this trial indicates that if the technology continues to evolve and prices drop that LEDs could help halve the use the energy used by lighting in commercial buildings.