Techno-fixes for climate change

Last week I presented at the Australian Academy of Science on ‘techno-fixes for climate change’. This talk was part of an AAS series organised by Bryan Gaensler called “Science Fiction becomes Science Fact“.

My talk was vodcast, and goes for 38 min, followed up by about 17 min of Q&A with the audience at the Shine Dome in Canberra (Australia). In it, I discuss climate scenarios, the energy problem, advanced nuclear energy, plasma-arc torches, geo-engineering, vertical farms, desalination, synthetic fuels, and much more. I also introduce the paradigm of ecomodernism.

I hope you enjoy it.

It was also covered in a report on BuzzFeed.

Tunnel Vision at the Climate Council

GR_April2015_CCCGuest Post by Geoff Russell. Geoff recently released the popular book “Greenjacked! The derailing of environmental action on climate change“.

The Climate Council has a new report out. The Global Renewable Energy Boom: How Australia is missing out (GREB) is authored by Andrew Stock, Tim Flannery and Petra Stock. The lead author is listed on the Climate Council website as a “Non Executive Director of several ASX listed and unlisted companies in the energy sector, ranging from traditional energy suppliers to emerging energy technology companies.” He’s also a chemical engineer.

Page 6 of the report begins by claiming “Globally, renewable energy’s contribution to global capacity and generation has climbed steadily upwards (Table 1)”.

Here’s line 4 from Table 1 except that I’ve added a column in red for 1973 using data from the IEA:

The percentage isn’t so clearly “climbing steadily upwards” now is it?

This table is one of a number carefully chosen or designed to enhance the images of wind and solar power and to misleadingly exaggerate their ability to prevent further destabilisation of the climate.

Misusing words

Page 8 follows with a claim in a large red font: “Global wind and solar capacity is growing exponentially”. This is accompanied by a graph which I’ve repeated here; but with a few annotations … in black. I’ll discuss them later.

Who think the graph supports the claim? It doesn’t. Exponential growth, by definition is growth with a regular doubling time, not regular increments … big difference! Growing exponentially is pretty easy for something trivially small, but it soon becomes hard and the graph shows clearly that both wind and solar are now only growing linearly; after about 2010 for solar PV and 2008 for wind.

The lead author is an engineer, so why call something exponential growth when it isn’t?

As the wind and solar contributions to an electricity grid grow, engineers expect stability problems to which there are currently no answers. AEMO’s 2013 report into 100% renewable electricty in Australia recommended underpinning wind and solar with either a biomass or geothermal baseload system to reduce the volatility; the sudden swings in supply. Germany obviously understands this and is now just burning half her forestry output annually. That’s about 30 million tonnes. This provides more electricity than either wind or solar.

Germany certainly had exponential growth in both wind and solar for some years, but that’s long gone. It took just one year to double the PV output for 2005; but the output from 2011 still hadn’t been doubled by the end of 2014. This slow down is despite solar providing just 6 percent of electricity. The wind power growth slowdown is even more advanced; it took eight years to double the 2004 wind output. Closer to home, South Australia has a higher renewable penetration than Germany, but no biomass baseload component, hence the stability risks which I suspect are behind the back-flip by long time nuclear opponent Jay Weatherill with the establishment of a Royal Commission into (almost) all things nuclear.

Understanding renewable growth

But am I being too cynical? The wind and solar growth lines above still look impressively steep. How can that be when Table 1, in contrast, shows a negligible percentage growth between 1973 and the present?

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The Limits of Planetary Boundaries 2.0

Back in 2013, I led some research that critiqued the ‘Planetary Boundaries‘ concept (my refereed paper, Does the terrestrial biosphere have planetary tipping points?, appeared in Trends in Ecology & Evolution). I also blogged about this here: Worrying about global tipping points distracts from real planetary threats.

Today a new paper appeared in the journal Science, called “Planetary boundaries: Guiding human development on a changing planet“, which attempts to refine and clarify the concept. It states that four of nine planetary boundaries have been crossed, re-imagines the biodiversity boundary as one of ‘biodiversity integrity’, and introduces the concept of ‘novel entities’. A popular summary in the Washington Post can be read here. On the invitation of New York Times “Dot Earth” reporter Andy Revkin, my colleagues and I have written a short response, which I reproduce below. The full Dot Earth article can be read here.

The Limits of Planetary Boundaries
Erle Ellis, Barry Brook, Linus Blomqvist, Ruth DeFries

Steffen et al (2015) revise the “planetary boundaries framework” initially proposed in 2009 as the “safe limits” for human alteration of Earth processes(Rockstrom et al 2009). Limiting human harm to environments is a major challenge and we applaud all efforts to increase the public utility of global-change science. Yet the planetary boundaries (PB) framework – in its original form and as revised by Steffen et al – obscures rather than clarifies the environmental and sustainability challenges faced by humanity this century.

Steffen et al concede that “not all Earth system processes included in the PB have singular thresholds at the global/continental/ocean basin level.” Such processes include biosphere integrity (see Brook et al 2013), biogeochemical flows, freshwater use, and land-system change. “Nevertheless,” they continue, “it is important that boundaries be established for these processes.” Why? Where a global threshold is unknown or lacking, there is no scientifically robust way of specifying such a boundary – determining a limit along a continuum of environmental change becomes a matter of guesswork or speculation (see e.g. Bass 2009;Nordhaus et al 2012). For instance, the land-system boundary for temperate forest is set at 50% of forest cover remaining. There is no robust justification for why this boundary should not be 40%, or 70%, or some other level.

While the stated objective of the PB framework is to “guide human societies” away from a state of the Earth system that is “less hospitable to the development of human societies”, it offers little scientific evidence to support the connection between the global state of specific Earth system processes and human well-being. Instead, the Holocene environment (the most recent 10,000 years) is assumed to be ideal. Yet most species evolved before the Holocene and the contemporary ecosystems that sustain humanity are agroecosystems, urban ecosystems and other human-altered ecosystems that in themselves represent some of the most important global and local environmental changes that characterize the Anthropocene. Contrary to the authors’ claim that the Holocene is the “only state of the planet that we know for certain can support contemporary human societies,” the human-altered ecosystems of the Anthropocene represent the only state of the planet that we know for certain can support contemporary civilization.

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Climate heating for 2014 in Australia

The Bureau of Meteorology in Australia has released its annual climate statement, for 2014. As expected, it was once again a hot year across the continent (and indeed, globally):

There is a lot of year-to-year variation driven by natural climate variability, but the running mean (10-year average) plots a relatively steady rise over the last 60+ years.

The mean continental temperature was 0.91 C above the average of the whole time series (starting in 1910, when sufficient station records were available), and that average reflects temperatures as they were in about 1980. If you look at the mean for the decade centred around 1914, it was ~1.3 C cooler than the year 2014.

Globally, the story is similar:

In this case the annual variations are more suppressed (averaging over a larger area, and including buffered oceans), but again the trend upwards is clear. Broad multi-decadal patterns are clear, and there has been some slowing of the rate of increase over the past decade.

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It’s time for environmentalists to give nuclear a fair go

This is an article by me and Corey Bradshaw, published today in The Conversation. I’m republishing it here.

Should nuclear energy be part of Australia’s (and many other countries’) future energy mix? We think so, particularly as part of a solution to reduce greenhouse gas emissions and prevent dangerous climate change.

Is the future of biodiversity conservation nuclear?

Is the future of biodiversity conservation nuclear?

But there are other reasons for supporting nuclear technology. In a paper recently published in Conservation Biology, we show that an energy mix including nuclear power has lowest impact on wildlife and ecosystems — which is what we need given the dire state of the world’s biodiversity.


In response, we have gathered signatures of 66 leading conservation scientists from 14 countries in an open letter asking that the environmental community:

weigh up the pros and cons of different energy sources using objective evidence and pragmatic trade-offs, rather than simply relying on idealistic perceptions of what is ‘green’.

Energy demand is rising

Modern society is a ceaseless consumer of energy, and growing demand won’t stop any time soon, even under the most optimistic energy-efficiency scenario.

Although it goes without saying that we must continue to improve energy efficiency in the developed world, the momentum of population growth and rising living standards, particularly in the developing world, means we will continue to need more energy for decades to come. No amount of wishful thinking for reduced demand will change that.

But which are the best forms of energy to supply the world, and not add to the biodiversity crisis?

Assessing our energy options

In short, the argument goes like this.

To avoid the worst ravages of climate change, we have to decarbonise fully (eliminate net carbon emissions from) the global electricity sector. Wildlife and ecosystems are threatened by this climate disruption, largely caused by fossil-fuel derived emissions.

But they are also imperilled by land transformation (i.e., habitat loss) caused in part by other energy sources, such as flooded areas (usually forests) for hydro-electricity and all the associated road development this entails, agricultural areas needed for biofuels, and large spaces needed for wind and solar farms.

Energy density of different fuels. This infographic shows the amount of energy embodied in uranium, coal, natural gas and a chemical battery, scaled to provide enough energy for a lifetime of use in the developed world. Shown are the amount of each source needed to provide same amount of energy, equivalent to 220 kWh of energy per day for 80 years.

In the paper, we evaluated land use, emissions, climate and cost implications of three different energy scenarios:


  • a “business as usual” future dominated by fossil fuels
  • a high renewable-energy mix excluding nuclear promoted by Greenpeace
  • an energy mix with a large nuclear contribution (50% of energy mix) plus a balance of renewable and fossil-fuel sources with carbon-capture-and-storage.

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