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Valid question:
Will biodiesel make the problem worse? The problem: http://www.hubbertpeak.com/ http://www.dieoff.org/ http://hubbert.mines.edu/ Global climate change, poluution and habitat destruction are integral to the enrgy problem, obviously. (I wonder if large scale use could make the problem worse, and small scale use is a viable solution) (Let me preface; I do not propose doing nothing about our fuel/energy/pollution/predicament, I am only interested in not making things worse.) ~~~~~~~~~~~ RENEWABLE ENERGY SYSTEMS ENVIRONMENTAL ACCOUNTING: Emergy and Environmental Decision Making by Howard T. Odum; Wiley, 1996 ; http://www.amazon.com/exec/obidos/ASIN/0471114421 From page 314 we find that in 1993 total US fuel use was 4.78 x 10e24 sej (increasing about 2% per year ever since). From page 187 we find that total net solar radiation absorption for Alaska and the lower 48 was 4.48 x 10e22 sej. In other words, the US is presently using fossil fuels more than 100 times greater than the total absorption of solar radiation across the entire US. So-called "renewable" energy systems are evaluated differently than "nonrenewable" energy systems. In order to be "renewable", an energy system must produce enough net energy to reproduce itself. Different kinds of energy have different properties. For example, a BTU of cow dung is fundamentally different than a BTU of oil. Directly and indirectly it takes about 1,000 kilocal of sunlight to make a kilocalorie of organic matter, about 40,000 to make a kilocalorie of coal, about 170,000 kilocal to make a kilocalorie of electrical power, and 10 million or more to support a typical kilocalorie of human service. So when renewable energy systems are evaluated, both inputs and outputs must be converted to solar eMjoules ( or "sej") and compared. (There are ten different sets of equations to convert energy to sej: http://dieoff.com/emergy.pdf ). The difference between the sej input and sej output is known as the "net sej". Calculations show that solar cells consume twice as much sej as they produce. http://dieoff.com/pv.htm So even if all the energy produced was put back into production, then one can only build half as many cells each generation -- they are not sustainable. Even if the sej efficiency of solar cells doubled, ALL of the energy produced by would have to be used to manufacture new cells, which still leaves a zero net benefit to society! Traditional measures of "net energy" for solar cells may be improving but "net sej" may be getting worse because there are ten different sets of equations to convert energy to sej. The only way to know is to DO THE STUDY. http://dieoff.com/emergy.pdf Odum's eMergy ("eMbodied energy") calculations show that the only forms of alternative energy that can survive the exhaustion of fossil fuel are biomass (burning wood, animal dung, or peat), hydroelectric, geothermal in volcanic areas, and some wind electrical generation. Nuclear power could be viable if one could overcome the shortage of fuel. No other alternatives (e.g., solar voltaic) produce a large enough net sej to be sustainable. In short, there is no way out. from: http://www.egroups.com/message/energyresources/2968 ~~~~~~~~ In order to find out if a "renewable" energy source is really "renewable", one must convert the various energies to sej because a BTU's worth of solar is fundamentally different than a BTU's worth of oil. (There is no need to make the conversion for nonrenewables because they are only used once, AND according to the recent "Aggregation and the role of energy in the economy", by Cutler J. Cleveland, Robert K. Kaufmann, and David I. Stern, price accounts for the difference in energy quality. So around the same time an oil field becomes "unergetic", it becomes "eneconomic".) Another way to look at it would be if solar panels were made using only the energy from other solar panels, they would cost a fortune to manufacture. ~~~~~~~~ The following observation is hugely significant to any solution to our woes: quote: That means we will never be able to make large scale biodeisel work - for the US fossil fuel budget, anyway. Don't get me wrong, I applaud the efforts made by biomass engineers, but the science says we can only make use of it on very small scales, with a "small return on investment" (Q in =< Q out , Q = work), or even at a [thermodynamic )loss [Q in > Q out). What I would like to know, is: can I produce enough biodiesel in a year from a portion of 1/4 - 1/2 acre home garden (climate zone 4), let's say, to run an emergency power generator (let's say my 5 Kw hydro plant is down for repair) for 72 - 96 hours a year (without devoting my garden to fuel)? Also, this question may be adressed elsewhere: I realize hemp contains lots of oils. Are data available on BTU returns from various plants, animals, etc.? Here is a synopsis of the situation: http://dieoff.com/synopsis.htm ~~~~~~~ Here is a basic understanding of the eMergy concept (eMergy is defined as EMbodied energy, "eMergy" is the all the energy that went into the product adjusted for "quality" - "energy quality" differs for fuels): quote: ~~~~~~~ Other news, If you hadn't heard: BRAZIL: September 26, 2000 SAO PAULO - Brazil may soon refine a diesel fuel from soyoil and sugarcane to cut pollution from its urban fleets and power farm machinery in rural areas, industry experts said yesterday. The special fuel, known as biodiesel, is compatible with conventional diesel engines and requires no modification to the motor. The fuel has the capacity to cut air toxins by some 90 percent, posing less of a health threat, they said. "Biodiesel ... has virtually all the chemical-combustive behaviours of normal diesel oil," said engineer Jose Carlos Laurindo at the Parana State Institute of Technology. As the world's top sugarcane growers, Brazil's cane millers make a large variety of sugars from their crush, but also distill the resulting liquor to make two types of fuel ethanol - hydrous and anhydrous alcohol. The boost in demand to Brazil's idle soyoil market would be a welcome side effect of developing the biofuel as the domestic crushing industry is faced with diving world prices and high supply. Brazil is the second largest soybean producer after the U.S. According to Oil and Gas Journal, the 98-year-old weekly trade magazine based in Houston, biodiesel has become the first alternative fuel to complete health effects testing as required by the 1990 U.S. Clean Air Act. While the biodiesel produced in the U.S. and Europe is made with a petroleum-based methanol, Brazil would prefer to use ethanol, which it makes from distilling sugar cane liquor. Brazil also considers the burning of methanol an environmental hazard. "We are looking to break with European production of biodiesel which involves methanol. We will use ethanol made from sugarcane," said Germano Ottmann, production director at COAMO, a large co-operative whose laboratories are testing a biodiesel made from soyoil and ethanol. Hydrous alcohol is used in vehicles requiring special engines while anhydrous alcohol, its chemical counterpart, is added to all gasoline sold in the country to form a mix known as "gasohol." "We have an abundant supply (of ethanol) in Brazil and it pollutes less than the petroleum-based alcohol (methanol)," Ottmann told Reuters. COAMO is based in Parana, Brazil's second largest soy-producing state. But the fuels are not suitable for normal diesel engines. There has been talk, however, of mixing such alcohols with diesel oil for use in modified "green" bus fleets in some cities. IN SEARCH OF A MARKET Soon after OPEC hiked world oil prices 70 percent in 1973, Brazil came up with a "pro-alcohol" fuel programme to help reduce its dependency on oil imports and cushion its massive cane industry against volatility in world sugar prices. While the fuel may become an attractive alternative overseas, it remains to be decided where biodiesel could best enter the domestic market in Brazil. "To transport diesel into northern Mato Grosso is very costly. The state is a top soybean grower. In places such as these, (soy) biodiesel should be viable," Laurindo said. Mato Grosso, Brazil's leading soybean growing state, lies within a vast fertile plain in the country's centre-west region. In terms of infrastructure, the state has relatively little freight rail or river transport available and almost all goods must be moved by truck at a high cost. However, Ottmann said the soyoil-based fuel would usually cost more than conventional diesel and would find a better consumer market in the country's major cities because of tightening regulations on air pollution. "Biodiesel will never compete with the price of diesel. It will exist because of government regulations on pollution in cities such as Curitiba, Sao Paulo, Rio de Janeiro and Porto Alegre," said Ottmann, noting a handful of state capitals which also represent Brazil's largest metropolitan areas. "A mixture of about 20 to 30 percent in conventional diesel will greatly diminish the pollution problems of the major urban centres," said Ottmann. "I imagine production in Brazil will start because of environmental, not commercial, reasons." Brazil may take its lead from the United States where states such as Arizona, Ohio, Maryland, New Jersey and Delaware have already approved the use of biodiesel as an alternative fuel and have allowed fleet operators to convert to biodiesel fuels rather than buying new vehicles to comply with clean air mandates. "If biodiesel goes into production in the major cities, it will create demand that will enliven the soyoil market, which is dead at the moment," said Ottmann. Story by Reese Ewing REUTERS NEWS SERVICE http://www.planetark.org/dailynewsstory.cfm?newsid=8326#top ~~~~~~~~~ Another point of view: 1) 1) If "biomass (burning wood, animal dung, or peat), hydroelectric, geothermal in volcanic areas, and some wind electrical generation" are alternative energy sources that "can survive the exhaustion of fossil fuel" then there is a way out- and they are the way. It will require a major restructuring and reduction in size of human society, but "necessity is the mother of invention," and "when you know know you're going to be hung in a fortenight, it concentrates your mind wonderfully." (That's the terrible problem of denial: we don't know we're being hung). 2) Unfortunately talk of "eMjoules" and "sej input, sej output" does not a simple explanation make. How did we manage to survive for 500,000 years without doing our set of ten mathmatical Emergy calculations each day along the way? I don't think it has to be quite so complicated. What's needed is a different mind set, not a different equational set. It's really quite simple- we live on a finite planet. Therefore, neither unlimited growth, nor unlimited consumption, nor unlimited wealth will be allowed. The problem is that the only way to get from here to there is by dieoff and anarchy (see Mad Max for more information). ~~~~~~~~~ IMHO the solution will be a (massive) change in lifestyles and priorities; a change of fuels can buy us some time, or it can make things even worse. ~~~~~~~~~ Another link if you don't already have it: - I'll collect some of these and put them in the energy links section if there is enough interest. http://www.biodiesel.co.uk/ ~~~~~~~~~ Great job with the forum, Shaun! Another great reference, and hopefully a source of helpful information.... Cheers |
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PS
For info on sustainable fuels, go to www.biofuels.fsnet.co.uk/sustain.htm Do not take the BABFO info as completely accurate - there are a lot of holes in their reasoning and a lot of figures not quite correct or incomplete. Terry UK |
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You are right, gobledeegook = too complicated (and rambling). I'll try to be more to the point in the future. If you see any misinformation, please point it out. I personally do not wish to be misinformed; thanks for the "heads up" on BABFO. You will find I am no advocate for anybody in particular, I am however an advocate for sustainability and realistic expectations.
It is a good thing, IMO, to attempt to establish a thermodynamic definition of sustainability from the outset, particularly when assessing various energy resources. Thanks for the link, Terry.... I realize we shouldn't jam the place with obscure and arcane links, but these links could go over to the links section..... |
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Hi Roger, well that was interesting but a little to much to bite off in one, since reanewability is what we are about i would like to go through your posting stage by stage,remembering that the Emperor wore no clothes please keep technochracy to a minnimum.Your opening lines-------From page 314 we find that in 1993 total US fuel use was 4.78 x 10e24 sej (increasing about 2% per year ever since).
From page 187 we find that total net solar radiation absorption for Alaska and the lower 48 was 4.48 x 10e22 sej. In other words, the US is presently using fossil fuels more than 100 times greater than the total absorption of solar radiation across the entire US. Question what is the total of petro diesel gasoline US burned per annum in metric tonnes. Q2 what is the total of coal gas heavy oil burned in the US in Mt Q3 what is the total land mass in hectares of the US, and what is the usable ie cropable land available,and the total suitable for short rotation coppice,also the solar absorbtion rate of the above stated.Please include land presently used for cattle but suitable for crops or SRC.  |
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Two fundamental definitions, semantics and why being on the same page can be so difficult:
"renewable" energy: quote: (note: that definition is in apparent violation of the second law of thermodynamics. If a source of energy can "reproduce itself" - assuming same 'quality' of energy, see above "gobledegook" - it is essentially a perpetual motion machine.) Sustainability; quote: (Note: "for ever and ever" is a very long time; using that definition, nothing can be sustainable. We need to start making use of energy sources that are both renewable and sustainable over periods of many hundreds to thousands of years.) We, as a culture do not have a very good vocabulary for energetics. To get "on the same page" we need a common language. The best we can do presently is mathematics, and there are three mathematical concepts that are dangerously misunderstood by most industrialized societies: 1) the concept of 0 (zero) 2) the concept of "for ever" (infinity) 3) the exponential function I might add one more for the economists: 4) the concept of 1 (as in" "one, that's all you get, and when that is gone, there will be zero left"). I started this thread to discuss sustainability, and how biodiesel may be considered a "sustainable" energy source. |
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Martin, I think you can find some answers to a couple of your Qs, at least, in the following Anual Energy Review from the DOE Energy Information Administration(for the US):
Annual Energy Review [url=http://www.eia.doe.gov/emeu/aer/contents.html ]Table of Contents[/url] Energy Overview 1 1.1 Energy Overview, 1949-1999 1.2 Energy Production by Source, 1949-1999 1.3 Energy Consumption by Source, 1949-1999 1.4 Energy Imports, Exports, and Net Imports, 1949-1999 1.5 Energy Consumption per Capita and per Dollar of Gross Domestic Product, 1949-1999 1.6 State-Level Energy Consumption, Expenditures, and Prices, 1997 1.7 Heating Degree-Days by Month, 1949-2000 1.8 Cooling Degree-Days by Month, 1949-2000 1.9 Heating Degree-Days by Census Division, 1949-1999 1.10 Cooling Degree-Days by Census Division, 1949-1999 1.11 U.S. Government Energy Consumption by Agency, Fiscal Years 1975-1999 1.12 U.S. Government Energy Consumption by Source, Fiscal Years 1975-1999 1.13 U.S. Government Energy Consumption by Agency and Source, Fiscal Years 1989 and 1999 1.14 Fossil Fuel Production on Federally Administered Lands, 1949-1998 1.15 Fossil Fuel Consumption for Nonfuel Use, 1980-1999 End-Use Energy Consumption 2 2.1 Energy Consumption by End-Use Sector, 1949-1999 2.2 Manufacturing Total First Use of Energy for All Purposes, 1994 2.3 Manufacturing Sector Inputs for Heat, Power, and Electricity Generation by End Use, 1994 2.4 Household Energy Consumption by Census Region, 1978-1997 2.5 Household Energy Consumption and Expenditures by End Use and Energy Source, 1978-1997 2.6 Household Main Heating Fuel and Presence of Selected Appliances, 1978-1997 2.7 Type of Heating in Occupied Housing Units, 1950-1997 2.8 Household Motor Vehicle Data, 1983, 1985, 1988, 1991, and 1994 2.9 Motor Vehicle Mileage, Fuel Consumption, and Fuel Rates, 1949-1998 2.10 Commercial Buildings Consumption by Energy Source, 1979-1995 2.11 Commercial Buildings Energy Consumption and Expenditure Indicators, 1979-1995 2.12 Commercial Buildings Energy Intensities by Building Characteristic 1995 Financial Indicators 3 3.1 Fossil Fuel Production Prices, 1949-1999 3.2 Value of Fossil Fuel Production, 1949-1999 3.3 Consumer Price Estimates for Energy, 1970-1997 3.4 Consumer Expenditure Estimates for Energy, 1970-1997 3.5 Value of Fossil Fuel Imports, 1949-1999 3.6 Value of Fossil Fuel Exports, 1949-1999 3.7 Value of Fossil Fuel Net Imports, 1949-1999 3.8 Major U.S. Energy Companies' Domestic Production and Refining, 1974-1998 3.9 Major U.S. Energy Companies' Net Income, 1974-1998 3.10 Major U.S. Energy Companies' Return on Investment, 1974-1998 3.11 U.S. Energy Activities by Foreign-Affiliated Companies, 1978-1997 3.12 Companies Reporting to the Financial Reporting System, 1974-1998 Energy Resources 4 4.1 Technically Recoverable Petroleum Resource Estimates, January 1, 1999 4.2 Crude Oil and Natural Gas Field Counts, Cumulative Production, Proved Reserves, and Ultimate Recovery, 1977-1998 4.3 Oil and Gas Drilling Activity Measurements, 1949-1999 4.4 Oil and Gas Exploratory and Development Wells, 1949-1999 4.5 Oil and Gas Exploratory Wells, 1949-1999 4.6 Oil and Gas Development Wells, 1949-1999 4.7 Costs of Oil and Gas Wells Drilled, 1960-1998 4.8 Gross Additions to Proved Reserves and Exploration and Development Expenditures by Geographic Area, 1974-1998 4.9 Major U.S. Energy Companies' Expenditures for Oil and Gas Exploration and Development by Region, 1974-1998 4.10 Liquid and Gaseous Hydrocarbon Proved Reserves, 1949-1998 4.11 Coal Demonstrated Reserve Base, January 1, 1999 4.12 Uranium Exploration and Development Drilling, 1949-1999 4.13 Uranium Reserves and Resources, 1999 Petroleum 5 5.1 Petroleum Overview, 1949-1999 5.2 Crude Oil Production and Oil Well Productivity, 1954-1999 5.3 Petroleum Imports by Type, 1949-1999 5.4 Petroleum Imports by Country of Origin, 1960-1999 5.5 Petroleum Exports by Type, 1949-1999 5.6 Petroleum Exports by Country of Destination, 1960-1999 5.7 Petroleum Net Imports by Country of Destination, 1960-1999 5.8 Refinery Input and Output, 1949-1999 5.9 Refinery Capacity and Utilization, 1949-1999 5.10 Natural Gas Plant Liquids Production, 1949-1999 5.11 Petroleum Products Supplied by Type, 1949-1999 5.12a Petroleum Products Supplied to the Residential and Commercial Sector and the Industrial Sector, 1949-1999 5.12b Petroleum Products Supplied to the Transportation Sector, Electric Utilities, and Total, 1949-1999 5.13 Fuel Oil and Kerosene Adjusted Sales, 1984-1998 5.14 Petroleum Primary Stocks by Type, 1949-1999 5.15 Strategic Petroleum Reserve, 1977-1999 5.16 Crude Oil Domestic First Purchase Prices, 1949-1999 5.17 Landed Costs of Crude Oil Imports From Selected Countries, 1973-1999 5.18 Value of Crude Oil Imports From Selected Countries, 1973-1999 5.19 Crude Oil Refiner Acquisition Costs, 1968-1999 5.20 Refiner Sales Prices and Refiner Margins for Selected Petroleum Products, 1983-1999 5.21 All Sellers Sales Prices for Selected Petroleum Products, 1983-1999 5.22 Retail Motor Gasoline and On-Highway Diesel Fuel Prices, 1949-1999 Natural Gas 6 6.1 Natural Gas Overview, 1949-1999 6.2 Natural Gas Production, 1949-1999 6.3 Natural Gas Imports, Exports, and Net Imports, 1949-1999 6.4 Natural Gas Gross Withdrawals by State and Location and Gas Well Productivity, 1960-1999 6.5 Natural Gas Consumption by Sector, 1949-1999 6.6 Natural Gas Delivered for the Account of Others, 1986-1998 6.7 Natural Gas in Underground Storage, 1954-1999 6.8 Natural Gas Wellhead, City Gate, and Imports Prices, 1949-1999 6.9 Natural Gas Prices by Sector, 1967-1999 Coal 7 7.1 Coal Overview, 1949-1999 7.2 Coal Production, 1949-1999 7.3 Coal Consumption by Sector, 1949-1999 7.4 Coal Exports by Country of Destination, 1960-1999 7.5 Coal Stocks, 1949-1999 7.6 Coal Mining Productivity, 1949-1998 7.7 Coke Overview, 1949-1999 7.8 Coal Prices, 1949-1998 Nuclear Energy 9 9.1 Nuclear Generating Units, 1953-1999 9.2 Nuclear Power Plant Operations, 1957-1999 9.3 Uranium Overview, 1949-1999 Renewable Energy 10 10.1 Renewable Energy Consumption by Source, 1989-1999 10.2 Renewable Energy Consumption by Sector, 1989-1999 10.3 Wood and Waste Energy and Alcohol Fuels Consumption Estimates by Type and Census Region, 1981-1999 10.4 Wood Energy Consumption Estimates by Sector, 1949-1999 10.5 Solar Thermal Collector Shipments by Type, Price, and Trade, 1974-1998 10.6 Solar Thermal Collector Shipments by End Use, Market Sector, and Type, 1998 10.7 Photovoltaic Cell and Module Shipments by Type, Price, and Trade, 1982-1998 10.8 Photovoltaic Cell and Module Shipments by End Use and Market Sector, 1989-1998 10.9 Alternative-Fueled Vehicles and Fuel Consumption by Type, 1992-1999 Environmental Indicators 12 12.1 Estimated Emissions of Greenhouse Gases, 1985-1998 12.2 Carbon Dioxide Emissions From Energy Consumption by Sector, 1980-1998 12.3 Carbon Dioxide Emissions From Energy Consumption by Sector by Energy Source, 1998 12.4 Carbon Dioxide Emissions From Energy Consumption for Manufacturing Industries, 1994 12.5 Methane Emissions, 1985-1998 12.6 Ozone Depleting Substances and Criteria Pollutants, 1985-1998 12.7 Emissions From Electric Generating Units, 1989-1998 12.8 Installed Nameplate Capacity of Steam-Electric Generators for Electric Utility Plants With Environmental Equipment, 1985-1998 Contact: Chuck Allen phone: (202) 586-5828 fax: (202) 586-9753 http://www.eia.doe.gov/aer/envir.html ~~~~~~~~ Hope that helps - anybody have the aggricultural numbers and references? |
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Martin, I am used to measuring oil or oil energy equivalents in barrels (42 US gallons). We need a conversion factor from barrels to metric tonnes - anyone?
(must be that "on the same page" deal again...) |
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I would be interested in knowing how much oil (petroleum) is used in the manufacture, storage and transportation of biodiesel, at this stage of the game.
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Roger: Glad to have you on the board. Feel free to post all your links on the "other energy options" forum, or wherever for that matter.
On Maui all biodiesel is made from used cooking oil, about 200,000 gallons per year presently. And most (I'm not sure of exact percentages) biodiesel on Maui is transported by Pacific Biodiesel using their three biodiesel trucks. When it gets to the point when we will be growing vegetable oil crops on Maui, the same will be true. On the manufacturing end, all the used cooking oil is delivered by pumping companies (most who use petroleum diesel, but some use a percentage of biodiesel). But, since they would be taking the used oil to the landfill if it wasn't used to make biodiesel, there is no more energy used because the Pacific Biodiesel Plant is located at the Central Maui Landfill. Storage - as far as I know all the biodiesel, with the exception of about 100 gallons Pacific Biodiesel keeps for their fuel pump (where I fill up) at their office in town is stored at the plant site in 6000 gallon tanks. No fossil fuels used for this purpose. Of course, this isn't the case for all biodiesel manufacturers, but if you think about it, it's in the best interest of the biodiesel companies to use their biodiesel in their vehicles and equipment so they can prove it works and I'm sure they save money on fuel costs Shaun |
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P.S. I forgot to add that all electricity at the Pacific Biodiesel plant is supplied by a generator that is fueled with biodiesel. You can view pictures of some of the Pac. Biodiesel vehicles and the generator at the Maui Biodiesel Project web page Biodiesel in Use.
Shaun |
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Roger
First, could you write in longhand & not in advanced mathematical terms please, as it will enable those of us without masters degrees to better understand your point of view. Next 1 metric tonne (1000kg) is equal to approx. 1150 litres or 304 US gallons or 253 Imp. gallons, based on the Bio-d having a specific gravity of approx. 0.87kg per litre. Next it takes about 15 units of energy to produce 100 units of Bio-d energy. I don't remember the address but I'm sure someone else here will give it to you. [This message was edited by Greg Aust on 08 October 2000 at 05:05 AM.] |
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Biodiesel is currently estimated to need 15% of the energy delivered to manufacture the fuel - about the same as petrodiesel. If the farmers use biodiesel, the mineral energy costs come down. If the straw and seed cake are burnt in power plant the energy obtained per hectare doubles. Don't forget that a crop needs about 1/2 year to grow and is collecting sunlight for all that time. The total energy collected is collossal
I agree that biodiesel could cause ecological problems if the world convererted to it at a breakneck pace. However that's not likely simply because it's more costly than petrodiesel. We also need to consider the damage done by petro diesel not least in vehicle emissions but also in accidents - like the one waitng to happen in Alaska when the next decent earth quake snaps the undersea oil pipelines. It's all a balance of risks... Petroleum will run out and the oilwells will dry up suddenly and we don't have very long to wait. Vegetable oils will not run out, but they are not cheap energy at any cost in the way petroleum is. Vegetable oils could cause ecological problems, but then so does ptroleum. On fuel produced. One hectare of Rapeseed delivers 2 tonnes of oil per hectare (1ha = about 2.3 acres). Oil palm can deliver 4 to 5 tonnes per hectare and they will grow in arid salt soil regions often unsuitable for anything else. Agreed virgin tropical rain forest land would be ideal, but that is mostly carved up for beefburger cattle. For the very long term aquatic algae look to be a good option. These are prolific oil producers, but efficient growing processes need development. Please note that ethanol, while potentially 100% renewable, has a far lower useful energy value due to the cost of manufacture. That said the Brazilians already supply 40% of their "petrol" from ethanol. |
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Thanks for the info, guys.... I am not ready to expend the energy needed to convert a car (that I do not own) to biofuels. I think I will continue bicycling. And researching.
However, I am interested in knowing if it is possible for me, with a 1/2 acre plot, to produce enough fuel, without devoting my garden to fuel crops, to power an emergency generator for up to 72 hours a year in case my hydro plant goes down, (and to power my chainsaw?) I will be listening to you all and hopefully learning. ~~~~~~~~~~ this cannot be true: quote: Have you heard of "flubber", the compound that bounces 15% than each bounce before? It has to take more than 100 units of energy to produce 100 units of energy, that is the definition of entropy (in violation of the first and second law of thermodynamics). Otherwise, we'd be in a universe of pure energy, and we'd get one hell of a "sun"-burn. Laws of thermodynamics:
~~~~~~~ Biodiesel appears to be a great small-scale fuel source for local applications. In industry, it faces some major energetic limitations, let alone the shady political ones. quote: what are those 6000 gallon tanks made of? How did they get where they are, there in Hawaii, a place with no metallic ore deposits? How were they made (how hot do you need to get Fe in the process of making stainless steel); what about the machinery that went into the smelter and foundary that went into creating the metal fabrication plants that went into making the presses and extruders that create tanks and thier associated plumbing? Should we trace the petroleum budget in modern agriculture? ~~~~~~~ I think Dave UK is thinking along the same lines as me.... but it is most definitely, assuredly, positively not inside the box: www.dieoff.org I am simply part of a (very slightly) larger chorus, of which most of you here, are part of. If we could get the harmony right, we might reach more people |
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LAND
Your plot of land might be just big enough for the requirements you quote. However, oilseed presses are extremely expensive so the economics won't stack up. You could try a coffee grinder and extract the oil with a solvent, but even this is pointless for such a small amount. Liquid biofuels really are a case of united we stand. You would probably be better off growing willow coppice and burning the timber biomass to generate steam. The "waste" heat would keep your house warm. ENERGY USED When I say that it needs 15 units of energy to make 100 units of biodiesel I mean to process the oil. In other words for 100 units of energy available in the original oil you get 85 units into the car's fuel tank. Thanks for the Entropy lecture, but please credit us with some intelligence. Obviously the oil energy has to come from somewhere. In the case of biodiesel from the sun via photosynthesis which is currently THE most efficient way to extract solar energy. I did not include this level of detail because I assume a certain level of logical intelligence from the reader. Ethanol another biofuel delivers far less useful energy. Not more than 35% of the original crop's energy value gets converted often much less than 35%. (Maybe this is where your odd figures on total energy used came from). PURISM WILL GET US NOWHERE I think your points on storage are excessively purist. Nobody is suggesting that biodiesel is 100% reneable or that it's infrastructure uses absolutely no fossil resources. At present, this would be totally impossible to achieve and it never will be possible if nobody starts somewhere. Biodiesel allows us to use existing infrastructure and to gradually introduce a fuel with a high renewable portion. Every tonne of Petrodiesel displaced is 3 tonnes less CO2 dumped into the sky. Added to that the seed plant's biomass (which is also a good fuel) we could be displacing at least another tonne of fossil fuel for generating electricity and saving another 3 tonnes of additional CO2. Biodiesel is about accepting that we have to continue from where we are now. We will never get people to throw away their cars at least not until there is no more fuel. By then the world's climate will have been so damaged that sea level will have risen and we'll have very little useful land on which to grow food never mind fuel. What are todays purists going to do then? "Told you so" and "Not my fault I used a bicycle" won't help very much. USEFUL LOBBYING Outfits like Greenpeace love to go for the big emotive hits "Ban the bomb" - "Save the whale" - etc. Fat lot of good they've done so far! Whales are still being destroyed and many specises are already past the point of no return. We just havn't noticed because individuals live for so long. The World still has enough nukes to blow us up 100 times over and now smaller countries are in on the act. All Greenpeace can offer for transport is bicycles, buses and the SmILE car. They openly hate diesels (used to be smokey so easy to complain about) yet modern diesels are clean, efficient, getting cleaner and run happily on a renewable fuel which is easily available if not as cheap as petroleum. We have to accept that we cannot continue as we are doing now. But, Green purists also have to accept that their ideal world is not going to happen - at least not until it's too late (if it's not already). By then "Told you so" and "Not my fault, I used a bicycle" is going to look really rather silly. OIL INDUSTRY Biodiesel actually gives us a very good chance of weaning the oilcos off mineral fuels. They make money from refining and distribution. What do they care if the crude feedstock is grown by farmers rather than dug out of the ground. They go for the cheapest fuel source that they can get away with. If biofuels were cheaper or petroleum more costly they would swap tomorrow and plough in huge research budgets. OTHER USES FOR PETROLEUM If we could stop burning petroleum we might have a chance to use it for materials such as plastics etc. These are far more valuable than simply burning the stuff. Incidentally a plastic adds little additional CO2 to the atmosphere because most of it's chemical energy is still bound up. You've already quoted all the details on that so I'll not repeat it here. MAINSTREAM POLITICS We have to convince politicians that there are viable renewable alternatives to fossil fuels. For all the reasons often discussed it won't be easy but it's our only hope. They want to remain ion power so have to have to be able to sell any changes to voters. The best option is new taxation policy to load fossil fuels and promote renewables. WHAT NOW? We have to fight the misinformation oozing from all sides (green and fossil fans) then cut the c**p and get on with pushing for achievable change in world energy use. It's probably already too late but at least we are trying. SOBERING THOUGHT I don't have the accurate quotation, but as Monsignor Bruce Kent said... "The planet will survive. Even if we let off all our nukes the sun will continue to rise and set. Life will eventually bloom again in all it's glory. Whether that life would include humans is open to question". [This message was edited by Dave UK on 10 October 2000 at 02:44 PM.] |
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Dave, I don't think willows would grow too well in my dry neck of the woods.... hemp would, though. Too bad it is illegal....
quote: Purism aside, a clear understanding of thermodynamics is paramount when discussing energy. It will keep you from losing your shirt in alternative energy schemes that will proliferate in the near future. (Why not get "purist?" What's to loose? If purism is telling the truth - no BS, no agenda, no advocacy, no ulterior motive, there is nothing to fear and I am for it. I am not "purist" anyway, I am a bit of a jaded skeptic that tends to ask questions) quote: That would work fine if we could just throw some seed into the ground. You see, an enormous portion of our hydrocarbon budget goes into intensive agriculture. That is where the energetics of scale come in. If we even attempt to go large scale with biofuels, we will likely make things worse (eat up the precious remaining easily-gotten hydrocarbon reserves (and arable land) that much faster - we're gonna need hydrocarbons for lubrication (these machines need grease, if for nothing else), and all the arable land we can use for food. If we don't get serious about this (ie. "purist") we're likely to screw things up as badly, or worse than they are now (because we think we're doing something useful). quote: You are right about the car thing. We've engineered ourselves into auto dependance. I think there are far greater gains to be made getting people off of combustion engines than simply converting to biofuels. (why do I care? I mean, i could just let the **** hit the fan without saying a thing - ignorance is bliss - just keep on coping with my own self imposed, preliminary "personal energy crisis", and let everyone else find out for themselves what has been known for decades. "told you so" is completely meaningless, particularly when the gravity of the situation finally sets in) I think you are missing something here. Whether or not there is an impending climactic catastrophe, or environmental nightmare or whatever, it is too late. We are in big trouble and it isn't (just) the atmosphere or the biosphere in general (although given 3000 billion more barrels of oil to burn, it would be). I thought you folks might be aware of this, I'm sorry for not being more clear here. We have burned ~900 billion barrels of oil since the turn of the century. Most of that has been consumed since WWII (past 60 or so years). There are an estimated 900 - 1400 billion barrels of left to be gotten. That means we are nearing, or at, a global peak in oil production. After that peak, production of oil will fall at a rate of ~2-3% per year, while demand continues to go up a percent or two per year. How much do you think a barrel of oil can cost? Maybe this isn't sinking in. The production of biofuels is completely dependant on fossil fuels. That is what I am trying to alert you to. You cannot: 1) create biofuels, 2) store biofuels, 3) transport biofuels, 4) or even use biofuels, without cheap, easy to get petroleum. So, within the next couple years, as world oil consumption bumps up against supply constraints, the price of oil will skyrocket. Therefore, the price of everything will skyrocket, from milk to baby rattlers to tires to contraception to fertilizer, pesticides and stainless steel. The costs of biofuel will follow the price of oil, until the "biofuel infrastructure" decouples from the petroleum infrastructure - completely. If that is to happen, it will have to happen extremely rapidly, because most researchers believe the world "Hubbert Peak" will occur between 2002 and 2007. That means, if biofuels are to be anything more than a gimmic to society, the necessary steps to building a petroleum independant biofuel infrastructure has to begin yesterday, worldwide. And that is why I am interested in small scale, local usage. There will never be a large scale biofuels infrastructure (unfortunately) for the reasons I outlined above and for the reasons Dave UK has given (the US/UK/industrialized-world/car relationship). When oil costs US$100 per barrel, it's gonna get pretty expensive to upkeep the biofuel distribution centers, amongst other things. ~~~~~~~~~~~~~~~~ quote: http://geopubs.wr.usgs.gov/open-file/of00-320/ http://www.RunningOnEmpty.org http://www.petroplan.co.uk/ http://www.hubbertpeak.com/ http://hubbert.mines.edu/ http://www.dieoff.com/ http://www.egroups.com/group/energyresources http://pub3.ezboard.com/fdownstreamventurespetroleummarkets http://csf.colorado.edu/longwaves/oct00/threads.html ~~~~~~~~~~~~~~~ By the way, the most efficient way to "extract solar energy" is to burn petroleum, particularly if it comes "bubbling up sweet crude" (easily extracted and easily refined). That is why we have used it, and not photovoltaics or biofuels, to run civilization. There is no other fuel that can compare with it's BTU's, transportability, ease of storage (and availability - for a very short while). That said, here is a calculation from a collegue: Biomass---- USA area =2.37 billion acres. assuming 1 billion acres useable, producing 4000lbs/acre/yr at 6000 btus/ lb. Per acre energy production would be 24 million btus. Total energy produced from biomass would be 24 quads. These numbers can be massaged up or down. However biomass is limited by fertilizer, water, soil quality, labor, and governmental wisdom. We need a mass tree planting program right now. It seems unlikely that we could produce more than 20 quads of biomass. However biomass is the most useful alternate energy because it is storeable and because the ashes may be crucial for fertilizer, and legumes in bio digesters may be able to produce food, energy, and nitrogen fertilizer. Reference----- 1 acre=.4047 hectares, 1 kwhr=3.6*10^6 joules=3412 btus, 1 btu=1055 joules, 1 quad=10^15 btus =1 trillion cuft natural gas=171.5 million barrels of oil, 1 barrel=5.25 million btus,, 1 kwhr=approximately 10,000 btus crudely based on power plant efficiency and heat pump COP, It takes very approximately 10,000 acres wood to fuel a 1 megawatt power plant which will produce about 8000 megawatt hrs/yr. USA 272 million pop, 3.7 million sq miles or 2.37 billion acres area, uses 95 quads energy/yr Conservation----The necessary back up is to reduce per capita consumption to a third of what we are using now. Europe gives us a partial solution. By building car scarce Sustainable villages which combine manufacturing, agriculture, and dwelling we can certainly reduce per capita consumption by 2/3. That will probably be much cheaper than massive wind and solar. I believe that biomass fuel, because of its fertilizer gathering properties, its constant availability, its relation to food, and because of its relation to nature is essential. ~~~~~~~~~~~~~~ Here is another quote (that I don't fully agree with... but it is appropriate here) quote: something to think about... |
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I am not fighting you.
quote: -- Thomas Hardy I just hope we understand what the stakes are. |
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