Does investment in clean energy require an international climate change treaty?

Just how crucial is the existence of a global climate change treaty to large scale investment in clean and renewable energy and the transition to a low-carbon economy?
Will national governments and companies, mindful of the potentially huge strategic, economic and commercial, opportunities offered by the clean and renewable energy sector, invest regardless of the existence of such a treaty?
The main argument in favour of a global treaty is that in the absence of one – which amounts to a legally binding obligation on all signatories – any attempt to cut emissions could lead to competitive disadvantage. A slowing of growth and loss of jobs to national economies, and a loss of contracts and markets to companies.
However, we only have to look around to see that at last one major country is speedily adopting clean and renewable energy in the absence of a treaty. As a developing economy, China is not even bound by the Kyoto Protocol, but it has committed itself to cutting its CO2 emissions per unit of GDP in 2020 by 40-45% compared to 2005 levels. To get there it plans to install 30GW of wind energy by 2020 and latest government statistics project that by the end of this year clean and renewable energy will account for 25% of its electricity generation. Clean and renewable energy in China is reportedly worth around US$17bn and employs close to 2 million people.
Meanwhile, here in Australia we are committed to 20% renewable energy by 2020 but we find ourselves debating whether it will create or destroy jobs. With our existing generating capacity rapidly reaching the end of it’s shelf life and an ever expanding power demand in Australia, I have little doubt that one of the next economic booms will be in the development of power generating capacity, its transmission and distribution.
The Hon Peter Lindsay, Member for Herbert, was heard last week in parliament to be promoting the need for a power transmission link between Townsville and the resource rich region around Mount Isa, and all renewable energy opportunities in between. While there are other proposals on the table – and I wish to remain politically neutral in my contemplation – this is one example of an initiative that would create jobs, link renewable energy opportunities to the grid AND promote the development of Australia’s resource industry. It seems to tick a lot of boxes! 
Of course, a global treaty would be hugely beneficial as a stimulus to the adoption of clean and renewable energy. But given political and commercial will of the sort that we are seeing in China, perhaps it is not absolutely essential. Or is it?

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