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English for Business IIb. Resources overview (completion, 3.10.2011). Karl Seeley, PhD Hartwick College. From March 3. Overview of history of growth of energy use Relative roles of different types of energy Overview of attributes of energy types. For today. EROEI Resource problems
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English for BusinessIIb. Resources overview(completion, 3.10.2011) Karl Seeley, PhD Hartwick College
From March 3 • Overview of history of growth of energy use • Relative roles of different types of energy • Overview of attributes of energy types
For today • EROEI • Resource problems • Limitations on exhaustibles • Climate change • Ecosystem condition
EROEI • Energy Return On Energy Invested • Energy contained in a source ready to be used, divided by energy expended to get it there • One measure of the physical cost of an energy source • Interaction between physical properties and technology
Resource problems • Limitations of exhaustibles • Climate change • Stressed ecosystems
“Peak Oil” • At some point, annual oil production must reach a peak • That’s implicit in exhaustible resource • Are we there yet? • Depends on your definition
Liquid fuels • Oil itself is diverse in quality and accessibility • There are similar hydrocarbons • Condensate, Natural Gas Liquids (NGL) • There are non-petroleum-derived liquids • Ethanol, biodiesel • “Liquids” have maybe plateaued, clearly not peaked
Fig 2. World production of “all liquids.” Image from "Oilwatch Monthly" http://www.theoildrum.com/node/7241
Oil, not liquids • If you focus on oil, then we haven’t yet made it back to level of July 2008
Fig 1. World production of conventional oil. Image from "Oilwatch Monthly" http://www.theoildrum.com/node/7241
Oil, not liquids • If you focus on oil, then we haven’t yet made it back to level of July 2008 • Ethanol has lower energy per volume than oil • So expanding “liquids” by replacing oil with ethanol may not mean increasing available energy • Ethanol and biodiesel have lower EROEI than oil • So more of what we have is going to keep extracting energy
Conventional oil, not just oil • Conventional oil: • On-shore or shallow water (not deep) • Liquid (not tar or shale) • Relatively sweet (not too much sulfur) • As you violate these conditions, costs go up • Monetary, but also environmental damage and CO2 per unit energy
Fossil alternatives to oil • Coal: outlier predictions that a peak is near, but consensus is for a large supply • Gas: looked scarce until improvement of shale technology • Maybe abundant, but EROEI is weaker, and bigger concerns about water pollution • Deepwater oil, tar sands, oil shales • Total quantities 2x, 3x “conventional” oil
Peak cheap oil • We probably have enough fossil fuel to keep current rate of expansion for a few more decades • But 20th century growth happened with oil that was physically cheap • How much do our economies depend on that? • Rather than on imperfect substitutes
The climate wrench • Climate change is a different problem: • Even if we have lots of fossil fuel, we don’t want to use much of it • What are the alternatives?
Wind again • In theory, can replace coal-fired electricity • Currently more expensive than coal • Though coal doesn’t have to pay for the costs it imposes through climate impact • Intermittency/storage problem is big • Norway preparing to offer “balancing services” • Turn hydroelectric on/off as needed to complement wind elsewhere in Europe • Need high capacity cables – and water! • http://www.theoildrum.com/node/7404
Desert solar • “Within six hours, deserts receive more energy from the sun than humankind consumes in a year.” • Dr. Gerhard Knies, http://www.desertec.org/en • That’s true, but it’s dispersed • Concentrating it, upgrading to industrial quality, is inherently expensive • Interesting side benefits • Use seawater for cooling, produce fresh water
Nukes to the rescue • A better fit for “business as usual” (BAU) • Predictable, controllable, base-load power • But • How quickly can you build out? • How worried are you about operational accidents? • How serious do you think the waste/decommissioning problem is? • How much uranium is there? • This is greatly extended if you use breeder reactors
Biofuels • Implications of large-scale replacement • EROEI • Carbon emissions
Large-scale biofuels • Food vs. fuel • 41% of U.S. maize crop currently going to ethanol (=15% of global maize) • http://www.msnbc.msn.com/id/40317079/ns/us_news-environment/ • But even more goes to animal feed • Europe might make ½ its gasoline if it stopped feeding animals (FAOStat + author’s calculations) • Global capacity? • Replacing world diesel capacity with palm oil would take 12x global palm-oil acreage (Data from FAOStat + author’s calculations)
Low EROEI • Biofuels have low EROEI • Corn ethanol ~1.2 (claims of ~0.8) • Some of that is electricity an expensive way of turning coal into liquid fuel • Biodiesel as high as ~4 • Sugar-cane ethanol ~6 • Oil is currently ~20 Biofuels won’t drive as vibrant an economy
Basic limitations • Low EROEI, low quantity is a problem for many alternatives to fossil fuels • Not just a biofuel problem
CO2 emissions Biofuels theoretically carbon-neutral
CO2 reduction Atmosphere Carbon
CO2 emissions • Biofuels theoretically carbon-neutral • Burning the fuel releases CO2
CO2 reduction Atmosphere
CO2 emissions • Biofuels theoretically carbon-neutral • Burning the fuel releases CO2 • But growing the plant pulled it from the air • But fossil fuel is burned in growing, processing • Converting forest land to oil palm releases huge amounts of CO2 • May outweigh CO2 reduction from replacing petroleum • http://www.geog.le.ac.uk/carbopeat/press/pr2.html
Biomass in general • At small scale, probably not problematic • But we’re not talking small scale
Biomass in general • At small scale, probably not problematic • But we’re not talking small scale • Global fossil fuel use is >1.5x total human appropriation of net primary production (NPP)
Biomass in general • At small scale, probably not problematic • But we’re not talking small scale • Global fossil fuel use is >1.5x total human appropriation of net primary production (NPP) • We’re taking 14-26% of NPP already • Most of that is not for energy • And it’s already causing 6th Extinction • Don’t know how much we can take without accelerating collapse
Responses I: Efficiency • Better insulation, better engines, etc. • Increased functionality with no increase in energy use • But we need to reduce from current levels • And watch out for Jeavons’ paradox • Smaller cars, smaller houses • This shades into …
Responses II: Doing with less • Living closer to work and services • Rearranging settlement patterns to allow less driving (less car-dependence) • More an issue in North America • But getting worse here • Diet changes • Mainly reduction in meat and animal products
Responses III: Price signals • Big role for price signals in inducing efficiency and conservation • No judgment about choosing a distant vacation or a big car • But you’re going to have to be very rich, or give up a lot of other consumption to get those things • At what point does this shade into slower GDP growth, or GDP decline?
Responses IV: Tech leap • Big improvement in algal biofuel? • Cheaper photovoltaic cells? • Cheaper electricity storage? • ??? • Long-term economic growth has been associated with use of larger gradients • Now talking about finessing smaller gradients • May be qualitatively different from experience
Dematerialization • The digital world promises production of wealth without using much stuff • A nice idea, but people who get rich there tend to buy physical things • Rich countries have only slightly “decoupled” GDP growth from increased resource use • Some of that is in the ability to import from Asia, where energy use is still rising quickly • Metabolic vision of economy suggests that high info flow depends on large energy flow
Conclusion? • No crystal ball • Tech breakthroughs can happen • But thermodynamics suggest they’ll be hard • Climatologists could be wrong about climate change • But the data keep coming in showing more effect than IPCC predicted • Yes, they were wrong, but that doesn’t help Fasten your seatbelts