Spot The Bulldozer  

Found it ?

The beast that is eating the bulldozer is a little device used for coal mining.

Most of the coal mines here aren't the "lop the top off the mountain" type discussed elsewhere recently. Instead we tend to have large open cut mines where vast amounts of coal are stripped out of the ground.



Coal quality around the country tends to vary - the mine this monster is working is a "brown" coal field in Victoria - brown coal is lowest quality and particularly polluting. As you go north up the east coast the quality of coal tends to get better and better, with most of the top quality black coal destined for export, particularly to China, which has a voracious appetite for the stuff - they are estimated to be consuming 2.2 billion tonnes a year of coal by 2010.

Coal is actually our largest export, which may give you a clue as to why Australia refuses to sign the Kyoto agreement - its easy to assume we're just being America's lapdog as usual, but in this case there is also a lot of money riding on the decision.



The monster in the pictures has some quite impressive statistics - you certainly wouldn't want to have a collision with it one the freeway:

The Large Bucket Wheel Excavator

* Stands over 95 metres tall
* Is over 215 metres long (2.5 football fields)
* Weighs over 45,500 tons (yes that's 45 thousand tons!)
* Cost US$100 million, took 5 years to design & manufacture and 5 years to assemble on site
* Requires 5 people to operate
* The Bucket Wheel is over 70 feet in diameter with 20 buckets each of which can hold over 15 cubic metres of material.
* It moves on 12 crawlers (each is 3.6 metres wide, 2.4 metres high and 14 metres long) - 8 in front and 4 in back
* It can remove over 76,455 cubic metres of overburden each day

Putting the Kyoto treaty aside, even locally, the variable coal quality here demonstrates just how difficult it is to take any sort of effective action on global warming without firm government intervention.

Australia operates a national electricity grid (well, it doesn't include WA, but they'd prefer to be a separate country anyway) which consists of a number of regional (state) grids connected by interconnectors. All electricity generated is sold into the national market, with generation rights directed to those generators who are willing to sell at the cheapest price via a complicated reverse auction process.

Because brown coal is, to be blunt, noxious crap, it tends to be much cheaper than the better quality black coal. As a result, those electricity generators who burn the brown coal have a financial advantage over those who burn the less bad stuff. So reducing greenhouse gas emissions using any sort of market based solution is a pipe dream.