Sunday, July 13, 2008

Global energy and global limits

We've come to an interesting zero-sum kind of place on the planet.


That is to say, interesting, in the sense of the purported Chinese curse: “May you live in interesting times.”


Opportunities for extracting resources are no longer limitless, and the planet's various reserve capacities appear in many cases to be tapped out.


Example:


Natural systems at one time presumably had a capacity for handling short term changes in inputs. A pulse of carbon dioxide could be absorbed by plants and marine life, as an example. Today, the absorption seems at capacity, and a pure chemical relationship has taken over—as we dump more carbon dioxide in, increasing levels of carbon dioxide dwell in the atmosphere; oceans grow more acid.


Example:


Humans don't have much opportunity for pioneering, for leaving civilization and going to never-inhabited places and tilling never-tilled soil. Polynesian voyagers ran out of new islands a millenium ago. American pioneers ran into a western ocean within the last few centuries. Virtually all the habitable lands on the planet are inhabited. It means that in many cases, if you're gonna do something new, you've got to shove something old out of the way.


Example:


The global food budget that suddenly seems limited. Where once we were assured that the American farmer had reserve capacity to feed the world. Now, take some acreage out of food grains for fuel, and there are shortages, price hikes.


Which leads to a thought about the carbon-neutrality of biofuels.


In theory if you sequester carbon dioxide in a corn plant or oil palm, and then convert it into fuel, and then release the same carbon dioxide in burning the fuel—well then, it's a balance. As much carbon in as out. No net impact on the atmosphere.


In practice, if you hadn't converted that land to grow fuel plants, the land would still have been growing other plants. The carbon would still have been sequestered in those plants, and it would arguably have been released considerably more slowly if you'd used them for food, or for timber, or even for a dedicated natural area.


Arguably, using biofuels is only preferable to using fossil fuels if no other fuel source is available.


It was interesting to see this article promoting non-carbon fuel sources: http://scienceblogs.com/energy/2008/07/a_planetary_perspective_on_the.php. Interesting, in this case, because the website is sponsored by the oil giant Shell, which is actively pursuing biofuels—including participating in research in Hawai'i on algae-based biodiesel.


The article by Solomon Hsiang argues that there may be geopolitical and economic reasons for moving from fossil fuel oil to biofuels, but that ultimately, they're not the best answer.


“Biofuels seem unwise,” he said, and he argued for non-fossil-based energy sources, like the sun, wind, ocean cycles of various kinds, including waves, currents, tidal flows and potentially, although he doesn't cite it specifically, ocean thermal energy conversion.


“The quantities of energy available from these sources are mind-boggling (they're often measured in petawatts), all we need to do is find the political maturity, will-power and cooperation needed to tap into them,” Hsiang writes.


None of this is intended to make negative judgments about Hawai'i biofuel efforts, which in many ways appear far more environmentally friendly than efforts elswhere on the planet.


If you're growing guinea grass on abandoned cane fields, it might be more appropriate to employ that property to grow a local fuel source using jatropha, kukui or even oil palm.


If global sugar prices are so low that a local sugar company can't survive on them, ethanol appears an appropriate alternative end product, particularly since sugar is so dramatically more efficient at producing ethanol than is corn.


And if the various efforts statewide to produce an algae-based diesel substitute are successful, they will do wonderful things for the Hawaiian economy and local self-sufficiency, though not much for the carbon dioxide balance in the atmosphere.

© 2008 Jan W. TenBruggencate