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Alternative Energy and Survival Copyright Ó 2005 by Todd Detzel Not to be distributed without permission
I. Introduction Most readers of this handout recognize that their way of life is dependent upon “energy slaves” provided to them by fossil fuels: coal, natural gas, oil and, although not considered a fossil fuel, uranium since it depletes. Despite that, people will still want to maintain their way of life even in the face of fewer slaves being available. However, this will be impossible as resources dwindle. The only choice will be to first reduce the number of slaves needed by changing the way we live. And, second, to make use, not of slaves, but willing partners, equals if you will, that are not used to any extent now. Understanding this partnership is crucial. For example, there is a great deal of talk of using various kinds of biomass for fuel. But if an excess of biomass is used for fuel our biomass partner will rebel and stop producing and no amount of force can make it produce again. It is as simple as that. Think of the once forested hills of Greece, Italy and, now, Haiti. Haiti’s mountains are currently being deforested/denuded to make charcoal for cooking in the cities since there is no other way to make money in rural areas to buy needed goods and food.
The focus of this presentation is upon a worst-case scenario where trucks are no longer bringing goods to our area and the grid is down permanently. There is little point in discussing intermediate scenarios where things are not too good but not too bad because too many variables make it impossible to focus upon those areas that are crucial to survival.
II. Non-Petroleum Energy Sources
The following list is fairly comprehensive but not exhaustive. Note that in some cases additional steps are necessary to use the energy source. For example, plant oils, with a few exceptions, cannot be used directly for biodiesel but must be esterified with methanol.
Phytofuels Algae Oil Wood Methanol Wood gas Space and water heating/cooking/baking Potassium hydroxide from ashes (for biodiesel) Making burnt limestone - agriculture Charcoal – blacksmithing/smelting/and, perhaps, gardening (Terra Preta) Pottery firing Steam/external combustion engines Thermionic electricity production Plant seed, nuts and fruit Oil
Plant starch/sugar/cellulose/biomass Ethanol
Human and animal waste/by-products Methane – anaerobic digestion of waste Oil – thermal depolymerization of offal
Human and/or animal power Treadmills Walking wheels Water lifts Rotary presses Cranking or pumping (as on a bicycle) wheels – rotary motion Foot treadles - linear or rotary motion Pushing/pulling – raising/lowering
Flowing Water Water wheels – rotary or linear motion Pumping water (hydraulic ram) Micro-hydro electric generators
Solar PV electricity Space heating – active and passive Heating water – active and passive Cooking/baking Food dehydration Refrigeration Lighting (light pipes)
Wind Linear motion – pump water Rotary motion – grind grain Wind electrical generator Pressurize air
Earth/soil Cold cellar Space cooling Heat reservoir for water-based heat pumps
Tidal Electrical power generation
Ocean OTEC/thermal differentials Electrical power generation Waves Electrical power generation
Energy Source Pros and Cons
Only possible major sources are reviewed.
Algae – It is possible to extract significant quantities of oil from pond-grown algae. Estimates range up to 250 gallons per acre of pond. There are no current algae operations for oil extraction so it is impossible to know whether production estimates are correct. Algae production in our area would be problematic since we do not have a long “growing season” or high summer temperatures to foster maximum growth. Dewatering and extraction of oil from the algae would require specialized equipment. It’s greatest advantage is that it would require little labor to produce the algae and the pond could be placed on land that would be inappropriate for crops. However, given summer evapotranspiration, significant quantities of water would be required. The oil extracted would be used for biodiesel after esterification.
Methanol – The production of methanol is problematic in that it would have to be produced locally by fermentation of wood chips using dedicated equipment and specific bacteria rather then natural gas as is now done. Further, it is fairly useless for anything except esterification with plant oils to produce biodiesel. Existing ICE motors cannot use methanol as a fuel.
Ethanol – The production of ethanol is less problematic then methanol. However, it is questionable whether non-industrial ethanol production has a positive return on energy invested. In addition, suitable crops must be grown and land and water used. Possible crops for source material include corn and sugar beets. Tri-fuel engines in Brazil can use ethanol directly as a fuel. However, standard ICEs in the U.S. cannot use it as a fuel. One possible use of ethanol is as a lamp fuel by combining the ethanol with a plant oil for use in an Aladdin -type lamp. But even this assumes that mantles are stored for long-term use.
Oil crops - I’m putting this in as a separate energy source even though it isn’t directly, so that I can discuss plant production for fuel in greater detail. There are a variety of plant and tree crops from which oil can be extracted. Although many people would vehemently disagree, I believe biodiesel is a dead-end energy source in a worst-case. The first reality is that the available cultivatable land is already marginal just to produce the food people need to survive. To me, it is ridiculous to believe that sufficient land could be taken from this limited amount to grow crops for fuel. The second reality is that these crops would have to be irrigated and, in some cases, fertilized. The third reality is that harvesting a meaningful amount of a crop requires harvesting equipment – and there is none here. Lastly, you can’t even use the oil directly (except possibly as a lamp fuel) but must further process it using even more energy.
Wood gas – This probably offers the highest energy return of any alternative fuel in our area. The wood used does not require special production and can be forest litter. It can be used directly in gasoline and diesel fueled engines. However, some modifications to the carburetion and injections systems have to be made since wood gas has less specific energy then regular gasoline and diesel fuel. This makes it a one-time option since it is unlikely that the modifications could be undone. Instead, the modified parts would have to be replaced. Starting the engine requires lighting the gasifier and waiting for sufficient gas to be produced. Further, a stock of wood would have to be carried to keep the gasifier going.
Wood gas technology is well proven over many years so it is not necessary to re-invent the wheel. And, of all the plant-based energy alternatives, only wood gas requires that no crop be grown.
Wood gas offers the possibility of replacing propane for hot water heaters, refrigerators and stoves. It would be necessary to devise a system to pressurize the gas. However, since gas appliances typically only need a few inches of water pressure to operate, it should be possible to build a relatively simple pressure system to achieve this.
Biodiesel – The sole advantage of biodiesel is that it can be used directly with any diesel engine and starting the engine requires nothing more then turning the key. However, it is extremely problematic to produce the fuel. First, a suitable oil crop must be grown, harvested and the oil extracted. This will require specialized equipment for both harvest and oil extraction. Second, methyl alcohol has to be produced. At this time, fermentation of wood chips is the only potential, local source of methanol. Third, sodium hydroxide is the usual “catalyst” to promote esterificaion of the plant oil and the methanol. To the best of my knowledge, no research has been done using potassium hydroxide obtained from wood ashes. Further, a diesel engine requires either an electric starter or a pony engine (run on wood gas?) to start it. They cannot be hand cranked like a gasoline engine. Therefore, most diesel engines will become unstartable once their batteries die. Finally, some biodiesel fuels have the potential to gel at low temperatures depending upon the source oil.
Methane – Methane production using anaerobic digestion is a well-proven technology that requires little specialized equipment. If pressurized, it could be used to replace propane. The essential problem is that it takes a significant volume of waste to produce useful quantities of gas. It would be most viable in a confined animal feeding operation where waste is concentrated.
Depolymerization – There is insufficient local offal for such a facility and the technology, while proven, has not been shown to be energy positive. The cost of such a facility would be very high.
Electricity – Electricity is of no value unless it is used to power equipment, appliances or lights. All electrical usage produces heat resulting in degradation of the unit and eventually failure. And, if it rotates, wear. Therefore, all uses will eventually fail. Most of these end uses are likely to be unrepairable after failure. The only hope would be to salvage replacements from deserted homes or businesses. Failing that, electricity will eventually go the way of the dodo bird.
Human/animal – These are technologies that have been proven over millennia.
Wood, solar, water, et.al. - There are many proven, simple technologies that are sustainable.
Conclusion
The take-home from this review should be that:
1. There are no panaceas; 2. That there is no one best energy solution and that a multitude of energy technologies are necessary to survive; 3. That macro-solutions for the entire area are more problematic then localized, micro-solutions on your road or at your home; 4. That the more high tech an energy solution is, the more likely it is to be unsustainable; 5. That only part of the survival equation has been reviewed.
It is the last statement that should raise warning flags. Survival is a gestalt, that is, survival is more then the sum of its parts. Having energy licked doesn’t mean you can get by without water to irrigate crops. It doesn’t mean you can survive if you don’t know how to grow and preserve food and so forth. Survival is a package deal. |