IEA: we're on track for 6 degree warming

You can't get much starker a statement than the one from International Energy Agency head Maria van der Hoeven, in relation to the latest edition of the IEA's Energy Technology Perspectives publication:

"Let me be straight. Our ongoing failure to realise the full potential of clean energy technology is alarming.

"Continued heavy reliance on a narrow set of technologies and fossil fuels is a significant threat to energy security, stable economic growth and global welfare, as well as to the environment."

This is the fourth edition of the IEA's Energy Technologies Perspective report, which attempts to map out what kind of transformation of our energy sector we would need to make in order to limit global warming to tolerable levels. This edition outlines a mix of technological solutions that are not all that different to what they have projected in the past:

-- Energy efficiency can deliver the largest, fastest and cheapest emission reductions.

-- Renewables have a large role to play and will grow to be a major source of supply if we implement policy to limit global warming to 2 degrees Celsius.

-- Natural gas will be important as a complement to the variability of some renewables and provide an important lower emission substitute for coal.

-- Nuclear will be important in countries that are willing to use it.

-- Proving-up carbon capture and storage is increasingly urgent and will be important to containing the costs of deep cuts.

But the particular highlight, or to be more precise, lowlight, of this report is that if governments don't do something urgently to wean ourselves off fossil-fuels, we'll most likely end up with global temperature rise of six degrees Celsius.

According to a 2010 paper by Sherwood and Huber, published in the Proceedings of the National Academy of Science, such a temperature rise would mean significant parts of the globe would be so hot and importantly humid, that it would be beyond humans to successfully adapt. We simply can't risk this kind of extreme temperature rise.

What's more, while avoiding this disaster would require very huge investments in energy supply and usage ($36 trillion more from today to 2050), it would deliver fuel savings that would outweigh the additional investments by $3 to $1.  Even with a 10 per cent discount rate, we'd end up with a net benefit of $US5 trillion, according to the IEA.

Unfortunately, the IEA says nine out of ten technologies that hold potential for major energy and CO2 emissions savings are failing to be deployed at the scale required. Hydro, biomass, onshore wind and solar photovoltaics are making sufficient progress, but several others are not. The IEA is particularly worried about slow uptake of energy efficiency, offshore wind and concentrated solar power but perhaps most of all it's worried about the complete lack of progress for carbon capture and storage of emissions from fossil fuel combustion.