An interesting find
While researching desalination, I found this interesting presentation (big PPP file) from the Water Corporation, including (slide 22) an estimated cost of $6.10 for a Kimberley pipeline with a capital cost of $11 billion. It’s from a 2004 GHD report, so there’s no question of its being a political stunt. The pumping requires two 600 MW power stations, which suggests (if my mental arithmetic is right) around 50kw-hours for each Kl of water delivered. I’ve extracted the relevant slide here.
As an aside, I saw in the Fin that the proponents are suggesting diverting as much as 80Gl of the flow to irrigation along the way, leaving only 120/Gl for Perth. It’s unrealistic to expect any contribution to the capital costs from irrigation users, so the entire capital cost would have to be spread over the 120/Gl supplied to Perth, and the unit pumping cost would probably also rise. The delivered cost could easily exceed $10/Kl.
Update As Rob Corr points out, towing icebergs from Antarctica would be a lot cheaper.
Further update Rob’s source puts the iceberg option at $3.20/kl, but I’ve found another study that puts it at $17.00. So a canal at $10/kl would split the difference between these two.
fn1. Either the implied rate of return here is well below the one I used or the capacity is higher. I’d guess they are assuming bond financing and low depreciation. Still this sounds like a more realistic figure than the $2 billion Tenix estimate being used by Barnett. The power stations alone would chew up most of that.