In a recent issue of Dissent magazine, a regular commenter here on Brave New Climate, industrial engineer Graham Palmer, engaged in a debate with Mark Diesendorf on energy futures. Unfortunately, this exchange of prose is not available online, although Graham did send me a scanned version (because of potential copyright issues, I won’t post it here). The promo from Dissent was as follows:

Mark Diesendorf says that nuclear energy is a very dangerous, complicated and expensive way of boiling water which is not a sensible alternative to renewable energy in the production of base-load electricity. Graham Palmer argues that because base-load electricity cannot be stored and wind and solar power are dependent on the wind and sun, renewable energy must be backed up by fossil or nuclear base-load capacity.

Fortunately, Graham also delivered a condensed version of his side of the debate to a national radio audience this weekend, via Robyn William’s ABC show Ockham’s Razor. With Graham’s permission, I’ve reproduced the transcript of his essay below (with a few hyperlinks and relevant pictures added), because I think it provides a useful context for discussion on the BNC blog. I trust you’ll find it interesting.

Coal dependence and the renewables paradox

(by Graham Palmer)

Listen to audio MP3 reading by Graham, here (6.5 MB, 14 min)

Just about everyone agrees that the most pressing challenge in averting climate change is reducing our dependence on coal. Like most environmentalists, I used to pretty much go along with the idea that a combination of wind and solar, combined with serious energy efficiency policies, could probably go a long way towards achieving that aim in the long term. But after two decades of intense international efforts, we seem to be running fast but actually getting nowhere. And growth in coal continues unabated. Even countries like Denmark and Germany, that have invested heavily in renewables over decades, despite managing modest relative reductions in emissions, have not found a way to displace their base-load coal with wind and solar. Indeed, despite around 100,000 wind turbines globally, and enormous investment in solar, there is not a single example anywhere in which a coal plant has been retired as a direct result of the installation of wind or solar. So what’s going on? To answer this, requires stepping back to 1865, and re-examining Stanley Jevons economics classic, The Coal Question.

Jevons proposed that an improvement in efficiency in steam engines would lead to an increase in the consumption of coal, arguing ‘It is a confusion of ideas to suppose that the economical use of fuel is equivalent to diminished consumption. The very contrary is the truth.’ His logic was impeccable – an improvement in efficiency led to the widespread diffusion of Watt’s steam engine, driving the industrial revolution. In fact, some ecological economists believe that improvements in technological efficiency, and the accompanying productivity gains, actually enable the increased affluence and population that are the primary drivers of resource depletion and pollution. Consider the substantial efficiency gains of modern aircraft and jet engines that have been achieved without a carbon price – fuel costs have always been a large proportion of airline operating budgets – we now have more efficient aircraft flying an expanding middle class, consuming more fuel than ever before.

Jevon’s Paradox helps explain why we continue to use more energy, and reveals one of the hidden traps of carbon pricing, but why hasn’t the enormous investment in renewables led to the retirement of coal plants?

The electricity network is based on one simple underlying principle – generate and distribute the power demanded by households and industry, every second of every year. It is this instantaneous demand that drives the highly dynamic operation of the market-driven network, and it is the peak demand that occurs for only a few hours a year that drives underlying capital investment. As electricity consumers, it is easy to think of our electricity connection as being somehow equivalent to an electrical tap in which there is a vast reservoir of electricity waiting to be consumed. But unlike our water supplies where there is more than a year’s supply waiting in dams, electricity must be consumed the very instant it is produced.

In one sense, power is what we use, but it is energy that we pay for. This subtle, but important distinction between power and energy is vital to appreciating the important difference between conventional generators that supply dispatchable power, and techno-renewables that supply non-dispatchable energy.

But green sources, such as rooftop solar, are amendable to community participation. These decentralized energy sources empower people, and encourage a richer understanding of the role of energy in our lives. Rooftop solar is community friendly, and although expensive, it offsets energy costs at the retail tariff rather than competing in the wholesale market.

But despite this, the sobering reality is that the intermittency of wind and solar requires the maintenance of conventional generation to ensure reliability of supply. Contrary to popular folklore, the mantra that ‘the wind is always blowing somewhere’ has no significance in electricity supply. The combined total of all South Australian wind farms, which make up around half of Australian wind capacity, can be counted on to supply a mere 3% of their rated capacity during periods of peak demand. Even adding in Victoria’s substantial wind capacity does little to improve this ‘reliable minimum’. Similarly, maximum wind power is just as likely to be developed when it is least needed.

Unlike wind, solar benefits from the regular daily correlation of daytime demand and sunlight, but regrettably, the correlation is too weak to ensure reliability of supply. Household solar’s greatest strength should be in the highly valuable niche role of reducing network and peak generation costs during summer air conditioner usage. But the peak on the hottest days typically occurs late in the afternoon on week days as people arrive home from work, after solar output has fallen.

What does this mean in practice? When the wind is blowing, or the sun is shining, the fuel consumption of the conventional plants will be reduced. But the need to ensure reliable supply ensures that fossil fuel plants cannot be turned off. As much as these innovative technologies seem to offer an intuitive appeal to energy supply for a large sun-drenched continent, a reliable electricity grid requires reliable dispatchable supply. Technology cannot undo this enduring truth.

This is the renewable paradox – it is only the availability of a reliable grid that permits the intermittent sources to have any value in reducing emissions, but it is replacing the fossil fuel generators that provide the reliable backbone that remains pivotal to delivering deep cuts in emissions. Does it make sense to deploy intermittent renewables, en masse, while we still remain dependent on coal, and are forced to use the least efficient peaking gas turbines to backup for intermittent renewables, rather than installing high-efficiency base-load gas turbines in the first place?

Yet the idea of energy transformations, perpetual motion machines and fuel saving innovations is deeply embedded in society – from the American guru of energy efficiency, Amory Lovins’ proposals in the 1970s for a wind and solar based society, to the radical, eco-socialist model of the Australian ‘Beyond Zero Emissions’ plan.

It is difficult to overstate the enormity of the challenge in potentially reverting to a society based on naturally occurring solar and renewable energies. One only has to consider a pre-industrial farmer who, relying on his own labour from consuming foods grown with traditional agriculture powered by sunlight, could sustain 100 watts of sustained effort, requiring several hours work each day to feed one person. With the use of horses, he gained access to perhaps 400 watts per animal, substantially improving his labour productivity and lifting the standard of living of his family and village. A modern farmer driving a diesel-powered John Deere harvester now has access to 300 thousand watts, and with modern agricultural methods, feeds thousands. Similarly, consider the proposed use of concentrated solar-thermal for electricity – all solar technologies rely on collecting very low density intermittent energy over a very large area – a solar thermal plant requires 15 times the concrete and 70 times the steel as a modern nuclear plant to deliver the equivalent quantity of energy – both materials with a significant environmental footprint – and constructed on massive allotments in remote desert locations far from industrial and demand centres, subject to the vagaries of climate, cloud cover and sand storms.

Renewable energy technologies will continue to get more efficient and cheaper. But taking a diffuse, intermittent, energy source and converting it into a reliable power source is not merely a case of stumbling upon a novel solution, or a project to be solved with the modern equivalent of an Apollo space program. These are inherent obstacles that will always remain as characteristic issues regardless of how cheap the basic generation technologies might become. Consider the technical brilliance of the Concorde passenger airliner – to some aviation observers of the early 1970s, it seemed perfectly obvious that the future of commercial aviation would be supersonic, but innovation was still not capable of undoing the physics of supersonic flight – both the supersonic boom and a substantial fuel consumption penalty compared to a Boeing 747 were inherent problems that undermined the Concorde’s business case for its 27 years of subsidised operation. For those with eyes to see it, there are indeed striking similarities with today’s energy debates.

Advocates of a twenty first century energy revolution should be reminded that Marchetti showed that coal’s displacement of wood in the early nineteenth century, then oil and gas’ displacement of coal, have followed similar progressions, taking 40 to 50 years to graduate from a 1 to a 10% share of global primary energy, or a hundred years to becoming the dominant primary energy source. Not even Henry Ford’s Model T, or big oil’s power was able to drive oil’s global penetration any faster.

So, is there a path out of Garnaut’s diabolical policy dilemma? While a carbon price will affect the relative price of alternatives to coal, it does not alter the physics of energy supply. Indeed, it is a triumph of hope over experience to assume that the emerging energy sources can take on a meaningful role for at least 2 to 3 decades.

The only feasible means to overcoming coal dependence is to deploy mature technologies that can meaningfully displace coal. Only gas and nuclear are capable of this pivotal role for the foreseeable future, with only nuclear providing the opportunity for deep cuts to emissions. But the most enthusiastic supporters of carbon mitigation are often the most strident critics of both of the only off-the-shelf, low carbon, base-load technologies, ensuring that deep cuts to Australian emissions prior to 2050 will remain an unfulfilled aspiration. Most of the claimed reductions in the proposed emissions trading scheme will come from purchasing forestry offsets, or in other words, paying landholders in Indonesia and New Guinea, not to chop down trees.

So what of the future? There is no fundamental reason why a suite of renewables could not play an important role in Australia’s energy needs in the second half of this century, but the obstacles to reaching this goal are much greater than merely an erratic policy environment, or resistance from the energy incumbents. Indeed, one can admire Europe’s willingness to embrace a new energy paradigm based around the mass deployment of renewables, but as they are now learning, the false promise of an early retreat from fossil fuels using a suite of renewables which are not fit-for-purpose is leading to higher energy costs, limited reductions in emissions, and delaying the long term transition to a low carbon future. Australia should be taking heed.