a Smelling Land

Smelling Land

You won't guess from the title that this is a most insightful book [1] on climate change and energy use. The author shows himself to be a writer of prose that is both lively and homely. He is also an engineer and an expert in energy-conversion machinery.

The book maps out how it is technically feasible to bring the developing world to our standard of comfort and wealth while at the same time reducing to zero mankind's intrusion on the environment. That is, technically feasible. A formidable obstacle that stands in the way is ignorance. Scott gives the following example.

As a response to the "energy crisis" in the 1970's the electric utility of Toronto, Canada, encouraged its customers to Turn Off The Lights. As a result, the downtown office towers, offensively blazing with light through the night, turned dark. This had an interesting consequence. Most of the electricity used by the lights turned to heat inside the building. As it was February, that heat was needed. As nothing was done about thermostat settings, the buildings started using lots of oil, the supply of which was what triggered the crisis in the first place. As a double irony, much of the generating capacity at Niagara Falls remained unused during the wee hours of the night.

What this episode brings out is a lack of understanding of the science underlying energy systems. My hunch is that now, forty years later, that lack persists. As Scott shows, the science needed is not rocket science. But there are some subtle aspects. In spite of the easy, friendly exposition you may have to read more than once to let it sink in.

Of course I'm not claiming that I can give here in a page the essence of a whole book. What I will try is to give a flavour of the subtle nature of the issues underlying the Kyoto protocols and more generally the response to global warming.

Here is a conumdrum: we describe our main problem as waste of energy. At the same time we remember learning in school the law of Conservation of Energy, a law that brooks no exception. How, then, can we "waste energy"?

Suppose you heat your house with a heat pump while your neighbour has old-fashioned resistive electric heat. One hundred percent of every kilowatt-hour of electricity your neighbour buys is turned into heat inside his house: he has one hundred percent efficiency. How can anyone do better?

All of the heat from the electricity you buy for heat is used to warm the great outdoors. Yet you get more than three times the heat inside your house than your neighbour gets for every dollar both of you spend on electricity. If your neighbour claims 100% efficiency, then you can claim 350%.

From the point of view of what matters, your neighbour has "wasted" two-thirds of the energy he buys for heating, even though the law of conservation of energy guarantees that none of it disappears, nor is any created by the magic of your heat pump.

It is because of paradoxes like this that Scott's "architecture of energy systems" de-emphasizes energy as such. In his view the system delivers services (heat or cool in the house, transportation, light) and these services are obtained by conversion of energy from one form to another. At the other end, the energy system takes fossil fuels as input, mostly.

Among the forms energy can take, electricity is desirable because it can be used provide to just about any service needed. It can pump heat into your house, light it, it can be used to cook food, propel a train. That is why Scott calls it an energy currency . To say that it is energy is a trite tautology.

The rub is that it is hugely expensive to store electricity. This is why electric cars have a small range. Not only does a gas tank cost a negligible fraction of the cost of a battery with the same energy capacity, but it can be filled in a minute while the battery takes hours to charge.

This is the huge advantage of gasoline as a car propellant. But a transportation system based on diesel, gasoline, or jet fuel depends on fossil fuels. This fact has led to irreparable damage to the environment and continues to do so on an increasing scale. To change this state of affairs it helps to look at Scott's architecture of the energy system and recognize gasoline, diesel, and jet fuel not as energy sources, but as energy currencies . (These currencies have crude oil as common source.) We then see that a conventional car runs to a considerable extent on hydrogen and that the main role of the carbon in gasoline is to liquefy the hydrogen in the gasoline. This hydrogen gives water as emission. Too bad that the liquefaction agent gives carbon dioxide and carbon monoxide as emissions, though it does its bit as carrier of additional energy.

What we need is an alternative currency that, like these, can be cheaply stored. That alternative currency is hydrogen . The only emission is water. The challenge is to make it sufficiently transportable. Liquefaction is one option among several.

Hydrogen is not only an alternative to the currently used carbon-based currencies. Whenever electricity cannot be used, hydrogen can. This points to an architecture of a sustainable energy system with renewable sources and electricity and hydrogen as currencies.

"Smelling Land" can be characterized as the scientific and technological conscience among Green writing. It is exceptional in the insights it derives from the author's scientific knowledge. It adds a whimsical, poetic turn that erupts into the title. Most of the readers of this book are, like me, landlubbers. In so far as they can smell, they can smell the sea when they approach the shore. I was surprised to learn that sailors sometimes smell the same smell. When they do so and they are in fog, this sets alarm bells ringing (or at least should). Apparently this peculiar smell is not the smell of all the sea, but of the strip of sea along any coast, with its distinctive littoral ecosystem. "Smelling Land" is chosen as title to emphasize the need to look at the same thing from more than one side.

An example of this unusual point of view is in Chapters 30 and 31, which is a scientist's view of nuclear energy. This view wrecks the facile categorization of the book as Green. The scientist's view gives data about availability of nuclear fuels to answer the question: Will we run out? The scientist's view compares fatalities per, say, megawattyear for nuclear and coal-fired power. From a scientist's view it is not necessary to build nuclear reactors in known earthquake zones. From a scientists's point of view it is only relative to a certain technology whether certain materials are "spent nuclear fuels". What is one technology's output, can be another technology's input. This relativity changes with advancing technology, which makes it irrational to look for sites where "spent" nuclear fuel can spend the next ten thousand years.

References

[1] Smelling Land by David Sanborn Scott. Queen's Printer, 2008.