[LINK] Geo-thermal: clean, permanent electricity

[Tom Koltai]

> -----Original Message-----
> From: link-bounces at mailman1.anu.edu.au 
> [mailto:link-bounces at mailman1.anu.edu.au] On Behalf Of 
> stephen at melbpc.org.au
> Sent: Saturday, 10 January 2009 4:31 AM
> To: link at anu.edu.au
> Cc: oz-teachers at rite.ed.qut.edu.au
> Subject: [LINK] Geo-thermal: clean, permanent electricity
> 
> 
> In terms of power generation, many think Geo-thermal is the 
> way Australia should go .. even wikipedia agrees. One recent 
> local start-up, (with help from ANU) Geodynamics has come a 
> long way .. and now first, 1MW in March.
> 
> 
> Geo-thermal, the perfect power, and we are the perfect 
> country for it. If this pilot is successful, we might readily 
> power all of Australia forever.

<snip>

Stephen and all,

Hot rock projects are wonderful - unfortunately there are two issues
that undermine the location of power generation in the centre of
Australia.  

Firstly, transmission loss on high tension power lines is 2.1 Kw per
kilometre (If there any transmission lines in the first place. - there
are not.)
So a Megawatt would be chewed up failrly quickly.

Secondly - Hot Rocks Powergen requires heat exchange from injection of
water. So first you need to get some water out there.
(Lots of piping required).

And of course then there's the power to run the pumps to get the water
out there. 
Ahhh, yes, a quick calc. 1 MW would not quite do it.

In other words, Australia is not quite geothermal enough.

In Stovepipe Nevada, they only have to drill 900 metres.
In Rotorua New Zealand, 750 metres and in Reykavik, Iceland, 600 metres.
And the Hot water is already there which means it merely needs to be
recirculated. (The problem is the heavy metals combined with high temp
alter the composition of the pipes and need to be replaced every 9
years.

Australia on the other hand has not had active magma movement (on land)
for 27 million years.
Although for small country towns with a large lake (eg Canberra) it
would be a great idea so they could power themselves and be truly self
contained..... Instead of having to buy expensive Carbon Credit rich
power from the Snowy's.

 
Ducking and running.........

Tom