THE worldwide need for so-called "hard" infrastructure such as roads, railways, ports, energy and communication networks, water and sewage has rocketed to the attention of policymakers worldwide in recent times - and so has the projected global cost of supplying that need.

When he chaired a G20 meeting in Washington last week, Australia's Treasurer Joe Hockey put the cost of supplying the world's infrastructure needs over the next couple of decades or so at a colossal US$80 trillion - or somewhat in excess of the size of annual global GDP.

This is 10 times what the Asian Development Bank (ADB) said three years ago would be needed in Asia alone to finance basic infrastructure over the coming decade, and approaching three times what the OECD has suggested will need to be spent by the world's advanced nations.