Climate change

June 6, 2011

Renewables and efficiency cannot fix the energy and climate crises (part 1)

 by Barry Brook
We must deal simultaneously with the energy-resource and climate-change pincers

The modern world is caught in an energy-resource and climate-change pincer. As the growing mega-economies of China and India strive to build the prosperity and quality of life enjoyed by citizens of the developed world, the global demand for cheap, convenient energy grows rapidly. If this demand is met by fossil fuels, we are headed for an energy supply and climate disaster. The alternatives, short of a total and brutal deconstruction of the modern world, are nuclear power and renewable energy.

Whilst I support both, I now put most of my efforts into advocating nuclear power, because: (i) few other environmentalists are doing this, whereas there are plenty of renewable enthusiasts  (unfortunately, the majority of climate activists seem to be actively anti-nuclear), and (ii) my research work on the energy replacement problem suggests to me that nuclear power will constitute at least 75 % of the solution for displacing coal, oil and gas.

Prometheus, who stole fire from the Gods and gave it to mortal man

In my blog, I argue that it’s time to become “Promethean environmentalists”. (Prometheus, in Greek mythology, was the defiantly original and wily Titan who stole fire from Zeus and gave it to mortals, thus improving their lives forever.) Another term, recently used by futurist Stewart Brand, is “Ecopragmatists”. Prometheans are realists who shun romantic notions that modern governments might guide society back to an era when people lived simpler lives, or that a vastly less consumption-oriented world is a possibility. They seek real, high-capacity solutions to environmental challenges – such as nuclear power – which history has shown to be reliable.

But I reiterate — this strong support for nuclear does NOT make me ‘anti-renewables’ (or worse, a ‘renewable energy denier‘, a thoroughly unpleasant and wholly inaccurate aspersion). Indeed, under the right circumstances, I think renewables might be able to make an important contribution (e.g., see here). Instead, my reticence to throw my weight confidently behind an ’100% renewable energy solution’ is based on my judgement that such an effort would prove grossly insufficient, as well as being plain risky. And given that the stakes we are talking about are so high (the future of human society, the fates of billions of people, and the integrity of the biosphere), failure is simply not an option.

Below I explain, in very general terms, the underlying basis of my reasoning. This is not a technical post. For those details, please consult the Thinking Critically About Sustainable Energy (TCASE) series — which is up to 12 parts, and will be restarted shortly, with many more examples and calculations.

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Renewables and efficiency cannot fix the energy and climate crises (part 1)

Boulton and Watt’s patented steam engine

The development of an 18th century technology that could turn the energy of coal into mechanical work – James Watt’s steam engine – heralded the dawn of the Industrial Age. Our use of fossil fuels – coal, oil and natural gas – has subsequently allowed our modern civilisation to flourish. It is now increasingly apparent, however, that our almost total reliance on these forms of ancient stored sunlight to meet our energy needs, has some severe drawbacks, and cannot continue much longer.

For one thing, fossil fuels are a limited resource. Most of the readily available oil, used for transportation, is concentrated in a few, geographically favoured hotspots, such as the Middle East. Most credible analysts agree that we are close to, or have passed, the point of maximum oil extraction (often termed ‘peak oil’), thanks to a century of rising demand. We’ve tapped less of the available natural gas (methane), used mostly for heating and electricity production, but globally, it too has no more than a few more decades of significant production left before supplies really start to tighten and prices skyrocket, especially if we ‘dash for gas’ as the oil wells run dry. Coal is more abundant than oil or gas, but even it has only a few centuries of economically extractable supplies.

Then there is climate change and air pollution. The mainstream scientific consensus is that emissions caused by the burning of fossil fuels, primarily carbon dioxide (CO2), are the primary cause of recent global warming. We also know that coal soot causes chronic respiratory problems, its sulphur causes acid rain, and its heavy metals (like mercury) induce birth defects and damage ecological food chains. These environmental health issues compound the problem of dwindling fossil fuel reserves.

Clearly, we must unhitch ourselves from the fossil-fuel-based energy bandwagon – and fast.

Meeting the growing demand for energy and clean water in the developing world

In the developed world (US, Europe, Japan, Australia and so on), we’ve enjoyed a high standard of living, linked to a readily available supply of cheap energy, based mostly on fossil fuels. Indeed, it can be argued that this has encouraged energy profligacy, and we really could be more efficient in the mileage we get out of our cars, the power usage of our fridges, lights and electrical appliances, and in the design of our buildings to reduce demands for heating and cooling. There is clearly room for improvement, and sensible energy efficiency measures should be actively pursued.

In the bigger, global picture, however, there is no realistic prospect that we can use less energy in the future. There are three obvious reasons for this:

1) Most of the world’s population is extremely energy poor. More than a third of all humanity, some 2.5 billion people, have no access to electricity whatsoever. For those that do, their long-term aspirations for energy growth, to achieve something equating that used today by the developed world, is a powerful motivation for development. For a nation like India, with over 1 billion people, that would mean a twenty-fold increase in per capita energy use.

2) As the oil runs out, we need to replace it if we are to keep our vehicles going. Oil is both a convenient energy carrier, and an energy source (we ‘mine’ it).  In the future, we’ll have to create our new energy carriers, be they chemical batteries or oil-substitutes like methanol or hydrogen. On a grand scale, that’s going to take a lot of extra electrical energy! This counts for all countries.

3) With a growing human population (which we hope will stabilise by mid-century at less than 10 billion) and the burgeoning impacts of climate change and other forms of environmental damage, there will be escalating future demands for clean water (at least in part supplied artificially, through desalination and waste water treatment), more intensive agriculture which is not based on ongoing displacement of natural landscapes like rainforests, and perhaps, direct geo-engineering to cool the planet, which might be needed if global warming proceeds at the upper end of current forecasts.

In short, the energy problem is going to get larger, not smaller, at least for the foreseeable future.

Renewable energy is diffuse, variable, and requires massive storage and backup

Let’s say we aim to have largely replaced fossil fuels with low-carbon substitutes by the year 2060 — in the next 50 years or so. What do we use to meet this enormous demand?

Nuclear power is one possibility, and is discussed in great detail elsewhere on this website. What about the other options? As discussed above, improved efficiency in the way we use energy offers a partial fix, at least in the short term. In the broader context, to imagine that the global human enterprise will somehow manage to get by with less just doesn’t stack up when faced with the reality of a fast developing, energy-starved world.

Put simply, citizens in Western democracies are simply not going to vote for governments dedicated to lower growth and some concomitant critique of consumerism, and nor is an authoritarian regime such as in China going to risk social unrest, probably of a profound order, by any embrace of a low growth economic strategy. As such, reality is demanding, and we must carefully scrutinise the case put by those who believe that renewable energy technologies are the answer.

Solarpark Mühlhausen in Bavaria. It covers 25 ha and generates 0.7 MW of average power (peak 6.3 MW)

The most discussed ‘alternative energy’ technologies (read: alternative to fossil fuels or nuclear) are: harnessing the energy in wind, sunlight (directly via photovoltaic panels or indirectly using mirrors to concentrate sunlight), water held behind large dams (hydropower), ocean waves and tides, plants, and geothermal energy, either from hot surface aquifers (often associated with volcanic geologies) or in deep, dry rocks. These are commonly called ‘renewable’ sources, because they are constantly replenished by incoming sunlight or gravity (tides and hot rocks) and radioactivity (hot rocks). Wind is caused by differences in temperature across the Earth’s surface, and so comes originally from the sun, and oceans are whipped up by the wind (wave power).

Technically, there are many challenges with economically harnessing renewable energy to provide a reliable power supply. This is a complex topic – many of which are explored in the TCASE series – but here I’ll touch on a few of the key issues. One is that all of the sources described above are incredibly diffuse – they require huge geographical areas to be exploited in order to capture large amounts of energy.

For countries like Australia, with a huge land area and low population density, this is not, in itself, a major problem. But it is a severe constraint for nations with high population density, like Japan or most European nations. Another is that they are variable and intermittent – sometimes they deliver a lot of power, sometimes a little, and at other times none at all (the exception here is geothermal). This means that if you wish to satisfy the needs of an ‘always on’ power demand, you must find ways to store large amounts of energy to cover the non-generating periods, or else you need to keep fossil-fuel or nuclear plants as a backup. That is where the difficulties really begin to magnify… To be continued…

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Part 2 will cover the ‘fallacy of the baseload fallacy’, ‘overbuilding’, costs, and evolution of real-world energy systems.

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