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DESIGN OF AN EARTH BATTERY SYSTEM
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DESIGN OF AN EARTH BATTERY SYSTEM
https://www.researchgate.net/publication/349214200_DESIGN_OF_AN_EARTH_BATTERY_SYSTEM
DESIGN OF AN EARTH BATTERY SYSTEM
BY
OGBONNA VICTOR CHIMAROKE 20141925043
A PROJECT SUBMITTED TO THE
DEPARTMENT OF MECHANICAL ENGINEERING,
SCHOOL OF ENGINEERING AND ENGINEERING TECHNOLOGY,
FEDERAL UNIVERSITY OF TECHNOLOGY, OWERRI
IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF BACHELOR OF ENGINEERING (B.ENG) DEGREE IN
MECHANICAL ENGINEERING
NOVEMBER, 2019
CERTIFICATION
This is to certify that this work, “DESIGN OF AN EARTH BATTERY SYSTEM” was carried out by Ogbonna Victor Chimaroke (20141925043) at the department of Mechanical Engineering, Federal University of Technology, Owerri.
Approved by:
………………………………….…. ….………………………………
DR. A.C. OKORONKWO DATE
(PROJECT SUPERVISOR)
…………………………………….. ………………………………….
ENGR. DR. G. O. OSUEKE DATE
(HEAD OF DEPARTMENT)
..…………………………………… …………………………………
ENGR. PROF. J. C. EZEH DATE
(DEAN OF S.E.E.T.)
…………………………………… …………………………………
EXTERNAL EXAMINER DATE
DEDICATION
To God Almighty for the grace, strength and wisdom He showered on us throughout the period of this project.
ACKNOWLEDGEMENT
I am most grateful to God almighty for the inspiration, knowledge and wisdom to write this project. I would like to appreciate my supervisor, Dr. A.C. Okoronkwo for his positive contributions towards the success of this work.
My appreciation goes to my Head of Department, Engr. Prof. G.O. Osueke, my class adviser, Engr. C. Onwuachu and the entire staff of Mechanical Engineering for their advice, support and contribution throughout my years in school.
I am grateful to my parents, siblings, friends and well wishers for their support and encouragement. I am forever indebted to them. God bless you all.
ABSTRACT
Earth battery involves the use of soil as the medium for generating electrical energy. Soil naturally contains energy in the form of telluric current that is capable of generating a DC supply electricity. Different types of soil contain different electrical resistivity and conductivity values. The selection of the clay soil is due to its low resistivity and high moisture content. Electrodes made of two dissimilar metals, copper and zinc, were used to conduct electricity. The consideration of the arrangement of the cells, the pH value of clay soil, and the conductivity of the electrodes were taken in order to achieve the optimum value of output voltage. Thirty (30) earth battery cells were arranged in series and each cell was isolated in a plastic container to maximize a DC output voltage of about 19v. This output voltage charges a battery of 12v through a charge controller incorporated in an inverter which powers the inverter and consequently produces an AC output of 850VA. This study on earth batteries using copper and zinc electrodes is very encouraging and portrays the viability of the earth battery as an alternative source of electricity in an environment where the supply of electricity is deficient.
TABLE OF CONTENTS
TITLE PAGE……………………………………………………………………..…i
CERTIFICATION………………………………………………………………….ii
DEDICATION……………………………………………………………………..iii
ACKNOWLEDGEMENT…………………………………………………………iv
ABSTRACT………………………………………………………………………..v
TABLE OF CONTENTS………………………………………………………….vi
LIST OF FIGURES………………………………………………………………..ix
LIST OF TABLES………………………………………………………………….x
1.4. SIGNIFICANCE OF STUDY.. 4
2.1 THEORETICAL FRAMEWORK OF THE STUDY.. 6
2.2 BACKGROUND INFORMATION ON EXISTING SYSTEMS. 7
2.3 EMPIRICAL REVIEW OF RELEVANT LITERATURE. 11
2.4 SUMMARY OF LITERATURE REVIEW… 12
3.1.1 Tools and equipment for construction. 13
3.1.2 Instrument for Data Collection. 14
3.1.9 Material of the electrode. 18
3.2.2 Arrangement of DC Supply of earth battery. 20
3.2.3 Procedures to assemble an earth battery system.. 24
4.1 PRESENTATION OF RESULTS. 30
CONCLUSIONS AND RECOMMENDATIONS. 40
5.2 CONTRIBUTIONS TO KNOWLEDGE. 40
LIST OF FIGURES
Figure 2.1: Earth battery cells connected in series………………………………………… 8
Figure 3.1: Soil horizons………………………………………………………………………. 14
Figure 3.2: Serial connection of batteries………………………………………………….. 22
Figure 3.3: Parallel connection of batteries……………………………………………….. 23
Figure 3.4: Cascade (series-parallel) connection of batteries…………………………. 24
Figure 3.5: Serial connection of 15 earth battery cells on bare earth……………….. 25
Figure 3.6: Serial connection of 15 earth battery cells in isolated plastic buckets. 26
Figure 3.7: Serial connection of 30 earth battery cells in isolated plastic buckets. 28
Figure 3.8: A schematic representation of an earth battery, inverter and battery connection………………………………………………………………………………………………………… 29
LIST OF TABLES
Table 3.1: Bill of materials for the design of earth battery………………………..13
Table 3.2: Soil groups……………………………………………………………..15
Table 3.3: Type of soil with average resistivity and typical resistivity value…….18
Table 3.4: Comparison among series, parallel and cascade connections…………….24
Table 4.1: Voltages of individual cells……………………………………………30
Table 4.2: Voltages of individual cells after 1 hour………………………………31
Table 4.3: Voltages of individual cells after 2 hours……………………….…….32
Table 4.4: Voltages of individual cells after introducing plastic containers………33
Table 4.5: Voltages of individual cells 1 hour after introducing plastic
containers………………………………………………………………34
Table 4.6: Voltages of individual cells 2 hours after introducing plastic
containers………………………………………………………………..35
Table 4.7: Voltages of individual cells with electrode length of 0.5m…………….36
Table 4.8: Voltages of individual cells with electrode length of 0.5m after
1 hour……………………………………………………………………37
Table 4.9: Voltages of individual cells with electrode length of 0.5m after
2 hours……………………………………………………………..….38
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CHAPTER ONE
Energy plays a very important role in the socio-economic and technological development of every nation. The electricity demand in Nigeria far outstrips the supply which is epileptic in nature. The country is faced with acute electricity problems which are hindering its development notwithstanding the availability of vast natural resources in the country. It is widely accepted that there is a strong correlation between socio-economic development and the availability of electricity.
Access to modern energy services is an enormous challenge facing the African continent because the energy is fundamental for socio-economic development and poverty eradication. Today, 60% to 70% of the Nigerian population does not have access to electricity (Hopkins, 1902). There is no doubt that the present power crisis afflicting Nigeria will persist unless the government diversifies the energy sources in domestic, commercial and industrial sectors and adopts new available technologies to reduce energy wastages and to save cost.
Power demand has increased with population growth, industrialization and civilization. Most householders are barely conscious of the conservative measures for the available limited supply, while the environmental impact has rarely been taken into cognizance by consumers.
Adequate power supply is an unavoidable prerequisite to any nation’s development, and electricity generation, transmission and distribution are capital-intensive activities requiring huge resources of both funds and capacity. In prevailing circumstances where funds availability is progressively dwindling, creative and innovative solutions are necessary to address the power supply problem.
An Earth battery consists of a pair of electrodes made of two dissimilar metals, such as iron and copper, which are buried in the soil. Earth batteries act as water activated batteries and if the plates are sufficiently far apart, they can tap telluric currents. Telluric current is an electric current which moves underground or through the sea. Telluric currents result from both natural causes and human activity, and the discrete currents interact in a complex pattern. The currents are extremely low frequency and travel over large areas at or near the surface of the earth. Earth batteries are sometimes referred to as telluric power sources and telluric generators. Common metals used as electrodes are copper and iron or zinc.
Earth battery was constructed by a Scottish inventor Alexander Bain in 1841. This invention was first used to power his electric clock. The combination the plates that he used is zinc and copper. An earth battery is the simple homemade cell. Almost any liquid or moist object that has enough ions to be electrically conductive can serve as the electrolyte can serve as the electrolyte for a cell (Cooper, 1995). Production of small amount of electricity can be demonstrated by insert two electrodes into a lemon, potato and glass of soft drink. These homemade cells are of no real practical use because it just can produce small current and cost far more per unit energy generated than commercial cells. Earth batteries were used around the end of the 19<sup>th</sup> and beginning of the 20th century to power telegraph lines. They were buried in convenient locations along the power lines and supplied free for that infrastructure. The technology was discarded and replaced with hydroelectric because hydro was a measurable, finite source that industry could use to make money.
The earth battery bears resemblance to the common chemical or acid battery. Basically, the battery consist of two metal sheets or rods; one copper or carbon and the other zinc or aluminium. These metals are present as positive and negative terminal of the battery. An earth battery acts as the electrolyte system in voltaic cell because the conductive plates from different location are buried in the ground. This cell operating just like operating devices, these devices were not continuously reliable owing to drought condition. To obtain natural electricity, experiment would thrust two metal plates into the ground at a certain distance from each other in the direction of a magnetic meridian or astronomical meridian (Kelvin, 1800).
Power is essential to everyone for their daily activities. We need power for almost everything. Some of these sources of power pose a threat to the environment and to human health (through the emission of carbon dioxide, carbon monoxide and other exhaust gases which will result to global warming) while some are intermittent.
The use of the normal battery or dry cell leads to the greenhouse effect. The environment will be contaminated because of the mercury, silver, lithium, cadmium, lead and acid in dry cell or normal battery. If these batteries are burned or land filled, the heavy metals in prototype can affect the environment and the effect faced in the long term is harmful.
There is an alternative way to reduce the cost and generate electricity through the soil. It is very easy to construct and also devoid of pollution. Other than that, relationship between combinations of material utilized as a part of the setup and the measure of voltage produce need to be considered wisely. Besides that, it is important to know the relationship between the types of connection to generate lots of energy.
Therefore, by using earth battery we will be reducing the greenhouse effect and give benefit to the green technology. However, earth battery produce low voltage compared to the dry cell battery.
Earth battery only requires constant enrichment of the soil/electrolyte. The plates, one copper and another iron or zinc, are connected above ground by means of a wire with as little resistance as possible. In such an arrangement, the electrodes are not appreciably chemically corroded, even when they are in earth saturated with water, and are connected together by a wire for a long time.
The main objective of this study includes;
· To generate power that is environmental friendly,
· With a cost-efficient energy source
· Provide a DC voltage of 19V from the earth battery
· To power some appliances with the power generated from the earth battery
This particular work will elaborately highlight the advantages of using earth soil chemical reactions and electron affinity based earth batteries to generate power that is environmental friendly, less expensive and provides a DC of 19V.
The major benefit or impact of this project work is that it will show the importance or relevance of untapped energy present in the earth crust in the form of telluric current. It also cuts across other fields of study such as Electrical Engineering and Soil Science Technology. It also shows the ever expanding correlation between these field of study.
This project work will focus on the design of the Earth battery . It will also emphasize on it’s working principles which includes the composition of the soil as an electrolyte and how it aids power generation.
The work will involve some principles of electrical engineering, chemistry and soil science technology featuring energy and power generation.etc.
It will be a pilot experiment that will be set up at the automobile workshop of Federal University of Technology, Owerri to generate a DC of about 19 volts from the soil (an earth battery) which will be converted to an AC of about 850VA using an inverter. This will power some selected appliances in a room.
This chapter will present the past articles that are related to this project. This case study review about the type of soil used for earth battery, potential difference or voltage output of two metal electrodes that have been chosen, the depth of the electrode in soil and the distance between two electrode. Basically literature review will expose the previous work to understand this project. Literature review also helps to find overall information about earth battery to make sure the objective of this project is fulfilled.
Basically the operation of the earth battery is the production of electrical energy from chemical reaction between two type of material of the electrode and the organic soil as the electrolyte medium. The effect of this reaction will convert the chemical reaction to electrical energy.
2.1 THEORETICAL FRAMEWORK OF THE STUDY
Earth battery is one of the alternative energy that can be used to produce electricity. It is the combination of clay soil and electrodes such as Copper electrode (Cu) with Zinc electrode (Zn) or other metals that can produce potential difference (V) and current (A).
It consists of conductive plates from different locations in the electro potential series, buried in the ground so that the soil acts as the electrolyte in a voltaic cell. As such, the device acts as a rechargeable battery.
When the electrodes are connected with the appropriate soil condition, the electrochemical reaction occur to ensue production of zinc ions from the zinc metal which travel through the ground toward the copper terminal. The chemical reaction of zinc will affect the plant and topsoil but it also affect groundwater, so it is important to limit the amount of zinc.
The soil is an unutilized chamber of natural energy. The chemical reaction in the soil produce independent ions which are left unresolved. The soil take actions as an electrolyte with two dissimilar electrodes buried in the soil and thus produce a potential difference. This process is called an ‘earth cell’. To increase the voltage, connection in series is needed whereas to increase the current, connection in parallel should be done. Earth battery consists of electrodes buried in the earth, as therefore constructed, have not been capable of giving an electromotive force greater than that obtainable from a single couple.
2.2 BACKGROUND INFORMATION ON EXISTING SYSTEMS
One of the earliest examples of an earth battery was built by Scottish inventor Alexander Bain in 1841. In addition to his battery experiment, he invented and patented the electric clock. One of the projected uses of his earth battery was to power his electric clock whose resulting voltage of Bain’s earth battery was about one volt. The Earth battery, in general, generated power for early telegraph transmissions and formed part of a tuned circuit that amplified signaling voltage over long distances.
The simplest earth batteries consist of conductive plates from different metals of the electro potential series, buried in the ground so that the soil acts as the electrolyte in a voltaic cell. As such, the device acts as a primary cell (device acts as a non-rechargeable battery).
Figure 2.1: Earth battery cells connected in series
The formal name of these current is “telluric currents. Because of the incorporation of these currents in the success of this type of battery, earth batteries are sometimes referred to as telluric power sources and telluric generators.
As was cited earlier, these batteries differ little from traditional batteries. They include conductive plates and include an electrolyte. The simplest earth batteries consist of conductive plates buried in different locations. The choices of these plates as is found in the accompanying table aids in the voltages created. When buried in the ground, the moist earth acts as the electrolyte found in a traditional voltaic cell. This form of cell, however, device acts as a non-rechargeable battery.
Due to the continuous variation of the moisture content in the earth’s soil, an earth battery is not continuously reliable. It should be noted these devices were used by early experimenters as energy sources for telegraphy. This helped explain the theory of telluric current. The long distances between telegraph offices aided engineers in their discovery there were electrical potential differences between most pairs of telegraph stations. This was cited as the result from natural electrical currents flowing through the ground. They were named telluric currents.
Some early experimenters did recognize that these currents were, in fact, partly responsible for extending the earth batteries’ high outputs and long lifetimes. Later, experimenters would utilize these currents alone and, in these systems, the plates became polarized.
Lord Kelvin adds to the study of the earth’s current. He cited that continuous electric currents flowed through the solid and liquid portions of the earth, and the collection of current from an electrically conductive medium in the absence of electrochemical changes (and in the absence of a thermoelectric junction. It should be noted that Lord Kelvin’s “sea battery” was not a chemical battery. Lord Kelvin observations there were variables, such as the placement of the electrodes in the magnetic field and the direction of the medium’s flow affected the current output of his device. Variables of this nature do not affect traditional battery operation.
To obtain this natural electricity, experimenters would thrust two metal plates into the ground at a certain distance from each other in the direction of a magnetic meridian or astronomical meridian. It was learned the stronger currents flow from south to north.
This phenomenon possesses a considerable uniformity of current strength and voltage. As the Earth currents flow from south to north, electrodes are positioned, beginning in the south and ending in the north, to increase the voltage at as large a distance as possible.
The current produced is highest when two events occur:
· when the two metals are most widely separated from each other in the electro potential series,
· when the material nearer the positive end is to the north and the negative end is towards the south. The plates, one copper and another iron or zinc, are connected above ground by means of a wire with as little resistance as possible. In such an arrangement, the electrodes are not appreciably chemically corroded, even when they are in earth saturated with water, and are connected together by a wire for a long time.
Also it was discovered in early experiments that the current would be strong when the northerly electropositive electrode is driven deeper into the medium than the southerly electrode.
In other experiments, a pair of plates with differing electrical properties and with suitable protective coatings was buried below the ground. A protective or other coating covered each entire plate. A copper plate could be coated with powdered coke. A layer of felt would be applied to a zinc plate. This type of enhanced aid to better use this natural electricity, were used fed electromagnets, a load, that were part of a motor mechanism.
Organic wastes as additives are used in the soil of ground-based earth batteries to improve its performance. Three types of organic wastes were studied; Palm Oil Mill Effluent (POME), pineapple waste and lemon waste. Each organic waste is added into separate damped clay soil containers with a ratio of 20:80.
2.3 EMPIRICAL REVIEW OF RELEVANT LITERATURE
In a related study carried out by: Khan, Saleem and Abas in Lahore (Pakistan), “Experimental Study of Earth Batteries”, Different combinations of metallic and non-metallic solid electrodes were investigated for maximum potential difference (Ryeczek, 1984). In view of robust and cost effective use of this natural power technology by unskilled village consumers. Most suitable combinations of the commonly available metals were selected for further detailed characteristic studies. Combinations of Magnesium anode and Coke cathode; Zinc anode and Graphite cathode; Aluminum anode and Carbon cathode; Zinc anode and Copper cathodes gave 2.05, 1.40, 1.10 and 0.9 volts per cell. Typical rated power of a single Zn-Cu cell was measured to be few tens of microamperes. Small power electronic devices such as calculators, electronic watches, baby toys and cell phones and white light LEDs were operated on site. The voltage level was found to increase linearly by connecting multiple earth battery cells in series like commercial lead acid battery. The load current was found to increase by connecting earth cells in parallel. The source current capacities were also found to increase by increasing surface areas of the electrodes. However, single cell voltage was found to remain constant irrespective of the electrode sizes. This paper reports detailed characteristic study of the most cost effective and accessible metal electrodes earth batteries. Operation of earth battery as a free electricity source was demonstrated successfully
2.4 SUMMARY OF LITERATURE REVIEW
In this chapter, literary works done by other researchers were reviewed or discussed. It began with conceptual framework of concepts such as; chemistry, energy and finally, earth battery.
Empirical framework of this study reviewed the works done by the past and recent researchers in related fields. A study carried out by Khan et al operated on earth battery as a free electricity renewable source of energy using different combinations of metallic solid, liquid and gas electrodes (Emme, 1900).
This project aims to efficiently harness the power generated from the earth that will not only be used to power an electric clock or used as an energy source in telegraphy but will be able to power some appliances in a room. The earth battery will produce a DC output voltage of 19V that will charge a battery which consequently powers an inverter to generate an AC of 850VA. This output power will be able to power some appliances in the home.
The materials used for this research work include soil(loam), electrodes (copper and zinc pipes), copper wire, aluminium wire, masking tape, iron saw blade, plastic container, screwdriver, inverter, multimeter, Charge controller, 12V Battery.
Table 3.1 Bill of materials for the earth battery
3.1.1 Tools and equipment for construction
1. Iron saw blade
2. Masking tape
3. Screwdriver
4. Pliers
5. Measuring tape
3.1.2 Instrument for Data Collection
A DT-830D digital multimeter was used basically for data collection and results were obtained from the experiment that was carried out.
The soil consists of one or more distinct layers called horizons. These layers are alluded to as O, A, E, B, C and R depending on their position and nature (Cooper, 1995).
· O: Layers overwhelmed by natural material. Generally not introduced under warm dry conditions.
· A: The mineral soil horizon that is as a rule at the surface or beneath an O horizon. It more often than not has more natural carbon than hidden layers. In some cases this layer is missing or truncated because of disintegration or evacuation. Likewise, all surfaces coming about because of furrowing, feeding, or comparable aggravations are alluded to as A horizon.
· E: Horizon characterized by eluviations (removal of materials such as silicate clay, iron, aluminum, or organic matter), if distinct from the A horizon. It is frequently not present and usually more pale-coloured than the A horizon.
· B: A skyline, framed underneath An, E, or O skyline, which is ruled by demolition of all or quite a bit of the first shake structure and which shows proof of soil development, for example, alluvial (moved down from an above skyline) amassing of silicate dirt, iron, aluminum, humus, carbonates, gypsum, or silica; improvement of soil shading or structure; or weakness, and so on.
· C: Horizons or layers, barring hard bedrock, that are minimal influenced by pedogenic (soil framing) procedures what’s more, that need properties of O, A, E or B skylines.
· R: Hard bedrock
Table 3.2 Soil groups
The soil groups are coarse soil, fine soil and other soils. In the coarse soils, it consists of gravel and sand while the fine soils consist of silt and clay whereas the other soil is organic soil (Daniel, 1800).
Gravel and sand contain of rock fragment of different sizes and shape that can be either rock fragment or single mineral. The term uniform was describe as the narrow range of particle sizes present while the broad range of particle sizes is describe as well graded (Dieckmann & George, 1885).
Silt is the intermediate among fined sand and clay. Silt is less plastic and more permeable than clay. Quick behaviour in silt is the impulse of silt to liquefy when shaken or vibrated. Dilatancy refers to the tendency to sustain volume increase when deformed (Deffeyes, 2002).
Clay consists of particles with a grain size of less than 4 micrometre and present in properties of cohesion and plasticity. Those properties are not present in gravel or sand. Cohesion is the fact that material will stick together whereas plasticity is the property that grant substance to be deformed without volume change or rebound and without cracking or crumbling (Deffeyes, 2002).
Organic soil is different category from coarse or fine soils and it does not behave like silt or clay if the organic content is high. When the content of the organic is small to moderate, it still contains the properties of silt or clays (Goodstein, 2005). Organic matter comprises of dead plant parts and creature and microbial waste items in different phases of disintegration. In the long run, these things separate into humus, which is generally steady in the dirt.
Soil conductivity is a measure of the amount of salt in the soil. Soil conductivity is an important material in an earth battery. Soil conductivity determines the output power of the cell. The conduction in dirt occur through the moisture-filled pores that happen between individual soil particles. Naturally excess salt in soils containing in arid and semi-arid climates. Salts level in the soil can increase as a result of cropping, irrigation and land management (Rogner, 1997). Although soil conductivity does not give a direct measurement of specific ions or salt compounds, it has been correlated to the concentrations of nitrates, potassium, sodium chloride, sulphate and ammonia. Therefore, the electrical conductivity of soil is determined by the following soil properties (Ruppert, 2005).
a. Porosity: The higher soil porosity, the more efficiently electricity is conducted. Soil with lot clay content has bigger porosity than sandier soil.
b. Water content: Dry soil is much lessened in conductivity than moist soil.
c. Salinity level: Increasing absorption of electrolytes (salts) in soil water will dramatically increase soil electrical conductivity. The salinity level in most soils is very low.
d. Cation exchange capacity (CEC): Mineral soil containing high levels of organic matter (humus) and/or 2:1 clay minerals such as Montmorillonite, illite , or vermiculite have a much higher ability to retain positively charged ions (such as Ca, Mg, K, Na, NH4, or H) than soil lacking these constituents. The presence of these ions in the moisture-filled soil pores will enhance soil electrical conductivity in the same way that salinity does.
e. Temperature: As temperature decreases toward the freezing point of water, soil electrical conductivity decreases slightly. Below freezing, soil pores become increasingly insulated from each other and overall soil EC declines rapidly.
Table 3.3: Types of soil with average resistivity and typical resistivity value [9]
3.1.9 Material of the electrode
The next parameter to be considered is the type of electrode. Generally, materials have characteristics behaviour of resisting the flow of electrical charge. Metal is used because of its high conductivity and electrical value. Different types of electrode gives different values of potential difference. Electrode selection is based on the conductivity value of a material. In this part, to increase the voltage, the electrode used must have features such as low resistivity/high conductivity, high melting point and durable.
Based on the requirements for electrodes, the following materials are the most suitable for the design of earth battery:
Copper has the highest conductivity of any non-precious metal and one that is 65% higher than aluminium. This, combined with its high ductility, medium strength, good resistance to corrosion etc makes copper the first choice as a conductor for electrical applications. Copper is low in the reactivity series (which means that it does not corrode easily). The standard electrode potential of a copper electrode is +0.337V
Zinc is a moderately good conductor of electricity. It is relatively resistant to corrosion in air or water, and therefore is used as a protective layer on iron products to protect them from rusting. The standard electrode potential of a zinc electrode is -0.7628V
Aluminum is soft, durable, lightweight, ductile and malleable metal with appearance ranging from silvery to dull grey, depending on the surface roughness. It is nonmagnetic and does not easily ignite (Kleveman, 2004) aluminum has about one-third the density and stiffness of steel. It is easily machined, cast, drawn and extruded. Aluminum is a good thermal and electrical conductor, having 59% the conductivity of copper, both thermal and electrical conductivity, while having only 30% of copper’s density. Corrosion resistance can be excellent due to a thin surface layer of aluminum oxide that forms when the metal is exposed to air, effectively preventing further oxidation. The strongest aluminum alloys are less corrosion resistant due to galvanic reactions with alloyed copper (Fesquet, 1878).
Brass is alloy of combination between copper and zinc. The physical properties of brass are malleable and ductile, with alloys that contain less than 35% zinc able to be cold- rolled. The conductivity of brass is only between 23 and 44% of the conductivity of copper, which is still fairly high. The uses of brass vary depending on the percentages of zinc and copper, and which other metals have been added to alloy to bring out specific properties (Katz, 2007). It conducts heat very well. Brass material with more zinc is stronger and harder. The color of brass is light yellow color close to that of gold. Brasses with less zinc are more of a red brown color.
After considering some factors such as cost, electrical conductivity/resistivity, durability of material, pollution and availability of materials, copper and zinc emerged as the most suitable electrodes for the earth battery design in order to achieve optimal performance.
The materials were carefully selected after some tests for best performance. The copper electrode was tested with a bar magnet to ensure that the best copper pipes were used.
The following procedure describes how to design DC supply of earth battery. The constant variables are the soil and metal electrode. The metal electrode made from copper and zinc has high value of conductivity is chosen. The combination of the soil and these electrodes with series-parallel arrangement may have a high output voltage and suitable with a small load such as 3V LED lamp. As the distance between the electrode and the interface between the two soils increases, the apparent resistivity decreases.
3.2.2 Arrangement of DC Supply of earth battery
The next parameter involved is the arrangement of the earth battery. The arrangement means how the cells can be connected. The arrangement that will be reviewed in this project is series, parallel and cascade (series and parallel). Method of arrangement of position or type of connection that will be done applies in order to optimize the output voltage from the DC supply of clay soil battery.
3.2.2.1 Series Connection
A series circuit is a circuit composed entirely of components connected in series. In a series circuit, the current flowing through each of the components is the same, and the voltage across the circuit is the sum of the voltages across each component. To increase the output voltage in a circuit, series connection will be used.
However, disadvantage of this circuit is that if one of the components of the series circuit is faulty such as overloaded or short circuit, the whole circuit will then be damaged.
For series connection:
Current
I<sub>t </sub>= I<sub>1</sub> = I<sub>2</sub> = I<sub>3 </sub>= I<sub>n</sub> (3.1)
Voltage
V<sub>t</sub> = V<sub>l</sub> + V<sub>2</sub> + V<sub>3 </sub>+……+ V<sub>n</sub> (3.2)
Resistance
R<sub>t</sub> = R<sub>l</sub> + R<sub>2</sub> + R<sub>3</sub> +……+ R<sub>n</sub> (3.3)
Figure 3.2: Serial connection of batteries
3.2.2.2. Parallel Connection
The second method is parallel connection. In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component as stated in Kirchhoff’s current law [24]. If two or more components are connected in parallel, they have the same voltage across their ends. The same voltage means the average of the output voltage of the connection. The advantage of parallel connection is that it increases the current at constant voltage at the supply end, and if there is a short circuit or overload, only the overloaded or short-circuited device will be damaged. This makes it easier to isolate faults and perform repairing to the faulty branches. In other words, if one branch fails, the other branches can still keep on working. However, the disadvantage is the output voltage is less than the output voltage of series battery connection.
For parallel connection:
V<sub>t</sub> = V<sub>1</sub> = V<sub>2</sub> = V<sub>3 </sub>= V<sub>n </sub>(3.3)
Current
I<sub>t </sub>= V<sub>t </sub>(1/R<sub>t</sub>) (3.4)
Resistance
1/R<sub>t</sub> = 1/R<sub>1</sub> + 1/R<sub>2</sub> + 1/R<sub>3</sub> +……+ 1/R<sub>n </sub> (3.5)<sub></sub>
Figure 3.3: Parallel connection of batteries
3.2.2.3. Cascade Connection
This method is the combination of series-parallel connection in one circuit. To calculate the output of the voltage and current of this circuit, the theory of series and parallel is applied. The series-parallel combination has same advantage as series and parallel, but this type of connection needs more battery to increase the voltage.
Figure 3.4: Cascade (series-parallel) connection of batteries
Table 3.4: Comparison among series, parallel and cascade connections
3.2.3 Procedures to assemble an earth battery system
1. The Iron saw was used to cut the copper pipes and Zinc pipes to a length of 1m.
2. A masking tape was used to hold the two dissimilar metals (copper and zinc) which are separated by an insulator to prevent lagging.
3. A pair of electrodes was inserted into the soil to form a cell.
4. Repeat the procedures above to produce 14 other cells.
5. The soil was moistened with about 5litres of water per cell.
6. The voltage of each cell was measured independently with the multimeter and the readings were recorded. Readings were also taken at intervals of 1hour.
7. The set-up was then connected in series with aluminium wire.
8. The voltage of the serial cell combination was measured using a multimeter.
Figure 3.5: Serial connection of 15 earth battery cells on bare earth
Due to the short circuiting of electrodes, the voltage cannot increase on bare earth surface. We need to isolate individual cells to add up the voltage. To demonstrate serial addition of voltages, 15 DC earth battery cells were prepared in separate plastic buckets and moistened with about 10litres of water each. The isolated earth battery cells were connected in series to increase the voltage as shown in Fig.3.5
Figure 3.6: Serial connection of 15 earth battery cells in isolated plastic buckets
After the individual cells were isolated from each other and the ground. The voltages of individual cells were measured and recorded. The overall serial voltage of the cells was also measured and recorded. The voltage increased drastically due to the isolation of the cells from each other and the ground. The overall voltage in serial connection was approximately the sum of the individual cell voltages.
The electrodes were cut to a length of 0.5m and the voltages of individual cells were measured and recorded. The overall serial voltage of cells was also measured and recorded.
15 more plastic buckets were introduced and 15 other pairs of electrodes were inserted into the buckets to give a total of 30 cells as shown in fig.3.6. The voltages of the new individual cells were measured and recorded. The overall serial voltage of the 15 new cells was also measured and recorded. The overall serial voltage of the whole 30 cells were measured and recorded at intervals of 1 hour.
Figure 3.7: Serial connection of 30 earth battery cells in isolated plastic buckets
The output of the DC earth battery is connected to a charge controller which regulates the amount of charge entering the battery. The charge controller consists of a diode that prevents charge reversal. The earth battery charges the 12V battery through the charge controller and the battery is connected to the inverter. The inverter has an in-built step-up transformer that boosts the input of the battery to an output of 850VA
<br clear=”ALL”>
Figure 3.8: A schematic representation of an earth battery, inverter and battery connection
4.1 PRESENTATION OF RESULTS
The various experimental procedures carried out have been described in the previous chapter. There were about 9 different tests undertaken to determine the voltage of individual cells and the overall serial voltage.
Table 4.1: Voltages of individual cells
Table 4.2: Voltages of individual cells after 1 hour
Table 4.3: Voltages of individual cells after 2 hours
Table 4.4: Voltages of individual cells after introducing plastic containers
Table 4.5: Voltages of individual cells 1hour after introducing plastic containers
Table 4.6: Voltages of individual cells 2hours after introducing plastic containers
Table 4.7 Voltages of individual cells with electrode length of 0.5m
Overall series connection for 30 cells = 19.18V
Table 4.8 Voltages of individual cells with electrode length of 0.5m after 1 hour
Overall series connection for 30 cells = 19.20V
Table 4.9 Voltages of individual cells with electrode length of 0.5m after 2 hours
Overall series connection for 30 cells = 18.75V
Inserting the electrodes directly into the earth decreases the overall output voltage when connected in series. This is because the arrangement is short-circuited when the electrodes are connected directly into the earth. Charges are also lost into the earth when these electrodes are inserted directly into the soil. This reduces the potential difference of the cells due to loss of charges.
When the plastic containers were introduced, the charges became isolated from the ground. The plastic containers served as insulators to prevent the diffusion of charges into the ground as the charges were now confined.
The overall serial voltage increased drastically from 2.5V to 9.87V. This result is approximately equal to the overall ideal serial voltage which is obtained by the summation of the individual cell voltages.
That is:
From equation (3.4)
V<sub>T</sub> = V<sub>1</sub> + V<sub>2</sub> + V<sub>3</sub> +………..+ V<sub>n</sub>
The earth battery was proven from the result to work best when damped. The salinity level of the soil drastically improves the conductivity of the soil, hence, making the earth battery more efficient.
CONCLUSIONS AND RECOMMENDATIONS
Results of experimental study on earth batteries using copper and zinc electrodes are very encouraging and portrays the viability of the earth battery as an alternative source of electricity. The initial results for week operation of earth batteries has shown reasonable potential for use in remote locations for signaling as well as charging cell phone and white light illumination applications. This interesting study has enlightened us on one of the sources of energy around us that is readily availability but has not been properly investigated.
5.2 CONTRIBUTIONS TO KNOWLEDGE
1. This study will serve as a guide for further studies in this area.
2. This study will help us understand the relationship between electricity and the earth.
3. This study will also provide the good knowledge base that will be useful in harnessing energy from the earth.
1. Further research work should be considered on other types of soils such as clay soil.
2. Further work should be done on how to embark on a larger scale production to harness energy from the earth which will yield larger amount of power for commercial and industrial purposes.
3. Further research work should consider replicating the methodology of this research and also adding sewage water on the earth batteries to increase its efficiency
4. Further research work should consider replicating the methodology of this research on other electrode material types such as silver, aluminium, brass etc
A. A. Fesquet, 1878. “Oliver Byrne, and John Percy,” The Practical Metal-worker’s Assistant. H.C. Baird & Co., pp. 529-530.
D. Goodstein, 2005. ” Out of Gas: The End of the Age of Oil. W. W. Norton’ Book ISBN 0-393-05857-3.
Daniel Drawbaugh, 1800s. “U.S. Patent 211,322 Earth battery for electric clocks”.
Dieckmann, George F., 1885. “U.S. Patent 329,724 Electric Earth Battery”.
E. Katz, 2007. “Alexander Bain”. The history of electrochemistry, electricity and electronics; Biosensors & Bioelectronics.
G. M. Hopkins, 1902. “Experimental Science: Elementary, Practical and Experimental Physics. Munn & Co.,. pp. 437 – 451.
H.H. Rogner, 1997. ” An Assessment of World Hydrocarbon Resources,” Annu. Rev. Energy Environ, Vol. 22, pp. 217-262.
J. Cooper, 1995. “Powering Future Vehicles with Refuelable Zinc/Air Battery,” Science & Technology Review, pp. 6-13.
K.S. Deffeyes, 2002 “Hubert’s Peak: The Impending World Oil Shortage,” Princeton University Press.: ISBN 0-691-09086-6.
K.S. Deffeyes, I.D. MacGregor, 1980. “ World Uranium Resources, Scientific America,” Vol. 242, pp. 66-67.
Lord Kelvin, 1800. Sea Battery: Method and Apparatus, US Pat. No. 4153757
L.C. Kleveman, 2004. ” The New Great Game: Blood and Oil in Central Asia,” Atlantic Monthly Press: ISBN 0-87113-906-5.
M. Emme, 1900s. “U.S. Patent 495,582 Ground generator of electricity”.
M.C. Ruppert, 2005. ” Crossing the Rubicon: The Decline of the American Empire at the End of the Age of Oil,” New Society: ISBN-13: 978-0865715400.
Ryeczek, 1984. “U.S. Patent 4,457,988 Earth battery”.
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5 Replies
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Marking to read later.
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I have made a couple of these, the output was very low from the ones I constructed. I found solar panels combined with batteries far ahead of this tech. But if was in an emergency could be used to power a radio.
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Ground generator of electricity
~3KW
https://patents.google.com/patent/US495582A/en
Description
M EMME. GROUND GENERATOR OF ELECTRICITY No. 495,582. Patented Apr. 18, 1893.
UNITED STATES PATENT OFFICE MICHAEL EMME, OE OAKLAND, CALIFORNIA.
GROUND GENERATOR OF ELECTRICITY.
SPECIFICATION forming part of Letters Patent No. 495,582, dated April 18, 1893.
i Application filed August Z9, 1892. Serial No. 444,391. (No model.)
To all whom it may concern
Be it known that I, MICHAEL EMME, a citizen of France, residing at Oakland, in the county of Alameda and State of California, have invented certain new and useful Improvements in Ground Generators of Electricity; and-I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.
My invention relates to chemical generators of electricity, a prepared body of earth being used as the support and exciting medium for the electrodes or elements. In a generator constructed in accordance with my invention, any desired number of elements may be assembled in the same piece of ground and coupled in series or multiple series to produce the electro-motive force desired. I find that if a series of galvanic couples are inserted in a body of ground so that a straight line will pass transversely through the several couples and the space between the several couples be made large comparatively to the distance between the two elements composing the couples, the couples may be joined for series in the same manner as if they were contained in independent Vessels. In order, however, to attain the best results it is necessary to prepare the body of soil immediately adjacent to the two elements composing a couple in a manner which will be hereinafter fully described.
The several features of novelty of the invention will be hereinafter more fully described in this specification and definitely indicated in the claims appended to this specification.
In the accompanying drawings Figure l illustrates an earth generator in which the several couples are arranged in series. Figs. 2 and 3 show a cross section of ground containing one couple. Fig. Ll shows wedge shaped elements with a suitable solution rich in oxygen, chlorine, bromine, iodine or fluorine, or with a solution of a salt of an alkali. As elements I prefer to use iron as a positive electrode and hard pressed coke carbon for the negative electrode. The positive electrode is preferably a U-shaped bar of iron round in cross section. The two limbs of the U straddle a rod of carbon. The iron should be soft wrought iron. Cast iron also can be used, but I find that cast iron gives a little less electro-motive-force, probably by reason of the percentage of carbon and other impurities contained therein. Magnesium also yields excellent results producing with carbon a voltage of 2.25. Zinc, aluminum or any metal with which the ground and its contained salts or exciting medium will develop electrolytic y action may be used with varying results.
In carrying my invention into practice I level a piece of ground of sufficient area to contain the generator. For instance, for three hundred positive elements each twenty inches long and two inches in diameter bent as indicated in Fig. 3, and three hundred negative elements fifteen inches long and three inches in diameter, the length of the piece of ground should be about one hundred feet and its width about three feet. I dig forty-three holes, at a distance of thirty inches apart from center to center, in a line as indicated in Fig. l. Each hole is ten inches wide and thirty inches broad and of a depth sufficient to contain the elements. The loose soil dug from the ground is mixed with a proper salt or acid to render the generator active. For instance, if the ground is a vegetable mold commercial concentrated nitric acid should be added in sufficient quantity to saturate the.
is then introduced, the composite elements being immersed in it. The several groups of elements thus arranged may be connected in series by conductors as shown in Fig. l, though the generator will act without any external conductors except the terminal wires. A generator constructed as above described will yield 53.85 volts and fifty-six ampres, developing a total of 3,015.60 watts, or about four horse-power. By increasing the number of cells the capacity of the generator may be correspondingly increased to any desired horse-power. The couples may ‘be joined in simple series or in multiple series. The prepared body of soil should be periodically moistened preferably with the acid with which it was treated when first prepared for action, and in a plant constructed for continuous action I prefer to provide a reservoir as indicated at A in Fig. 6 and run a pipe of a material not attacked by the acid throughout the plant providing nozzles over the several couples so that they may be moistened when desired. With provisions of this nature the soil may be kept in a substantially uniform condition and the generator rendered continuously serviceable. Any accumulation of oxides or other products of the reaction between the prepared soil and the elements may be removed and a clean metal surface exposed for chemical action by raising the positive electrode and then forcing it back into place again. The carbon may be cleansed by simply turning it Without lifting it from its place.
I find that the period of activity of the generator during which no addition of salt or acid is required increases with the length of service. For example, during the first day of use the exciting’ medium should be added after ten hours of Work, after which it will yield twenty-six hours of service, and then after another addition of excitant it will yield service for two days, and so on.
In Fig. l is represented a generator the several electrodes of which are composed of rods grouped in multiple and arranged as indicated in Fig. 2 where B represents the solid ground and C .the mass of prepared soil.
inferior results are obtained by such an arrangement) as indicated at G.
The dotted lines Fig. 5 indicate the directions of electro-motive-force in the internal circuits, 1, 2, 3, 4, 5, 6 being in one direction and 7, S and 9 in an opposite direction. There lines in Fig. 5, the solid ground acting as a h conducting medium. Thus the internal resistance of the generator is lowered and the output of the generator consequently increased. The fact that such internal circuits actually exist may be demonstrated by the interposition of a voltmeter in the ground between successive pairs of elements; the whole body of earth in the neighborhood of the generator seems to be permeated with stream lines of electric energy. p This fact probably assists in some Way to prevent polarization of the negative electrodes as the battery acts with great constancy.
Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-
1. A generator of electricity comprising a series of galvanic couples each couple being embedded in an electrolytic medium composed of earth mixed to a pasty consistency with an exciting solution the spaces between the several couples being occupied by unprepared earth.
2. A ground generator of electricity comprising a series of galvanic couples embedded in an electrolytic medium composed of earth mixed to a pasty consistency with a suitable excitant and filled in holes formed at intervals in the earth.
3. A ground generator of electricity comprising a series of galvanic couples embedded in the earth and connected in series relation, the distance between the several couples being large compared to the distance between the elements of any couple, and a reservoir for periodically supplying a moistening medium and maintaining the action of the generator.
In testimony whereof I affix my signature in presence of two Witnesses.
MICHAEL EMME.
Witnesses:
LINCOLN SoNNTAG, CHAs. SONNTAG.
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This reply was modified 2 months, 3 weeks ago by Bright_Sunday.
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This reply was modified 2 months, 3 weeks ago by Bright_Sunday.
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This reply was modified 2 months, 3 weeks ago by
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http://www.free-energy-info.tuks.nl/SChapt26.html
<font size=”2″ face=”Arial” color=”black”>There is nothing magic about free-energy and by “free-energy” I mean something which produces output energy without the need for using a fuel which you have to buy.
<font size=”2″ face=”Arial” color=”black”>The 3-Kilowatt Earth Battery
This battery does not need to be charged. Earth batteries are well known. They are pairs of electrodes buried in the ground. Electricity can be drawn from them, but they are generally of little interest as the power levels are not great. However, in his patent of 1893, Michael Emme, a Frenchman living in America determined how to get very serious levels of power from an earth battery of his design. In this particular unit which he describes in his US 495,582 patent, he gets 56 amps at just under 54 volts, which is three kilowatts or 4 HP. At that early date, there was generally, not much need for electricity, but Michael states that by selecting the number and connection method of the individual components, any desired voltage and/or current supply can be had. This, of course, is a simple system which involves no electronics.<font color=”red”>Please bear in mind that some forms of construction utilise strong acids and careless handling of strong acid can result in skin and other damage. Protective clothing should be used when handling acids and an alkali should be ready for immediate use if careless handling causes splashes.</font>
Summarising his patent, Michael says:
<font color=”blue”>My invention relates to chemical generators of electricity where a prepared body of earth is the support and excitation medium for the electrodes or elements. Any number of elements can be assembled in the same piece of ground and connected in a chain or series of chains in order to produce the desired voltage and/or amperage.</font>
<font color=”blue”>I find that several straight chains of elements can function separately provided that the gap between the chains is much greater than the gap between the elements which form the chain. Being quite separate, those chains can be connected in series to increase the voltage, or in parallel to increase the available current.</font>
<font color=”blue”>It is necessary to prepare the soil in the ground in the immediate area around the electrodes which form each element in the chain.</font>
<font color=”blue”>
Fig.1 shows five elements connected in a chain. This view is from above with the rectangles indicating holes in the ground where each hole contains seven separate pairs of electrodes.
Fig.2 and Fig.3 show how individual electrodes are inserted into the prepared soil “C” which is surrounded by untreated ground “B”. Electrode “D” is made of iron and “E” is made of carbon.
Fig.4 shows how wedge-shaped electrodes can be used as an alternative construction. The advantage is that it is easier to pull a tapering electrode out of the ground.
Fig.5 shows the internal current flow circuits which operate when a chain of elements is used. The arrows indicate the direction of current flow.
Fig.6 shows a convenient method for periodically moistening the prepared soil areas.Soil of any type can be adapted for use with an electrical generator of this kind by saturating the soil immediately surrounding each pair of electrodes with a suitable solution which is rich in oxygen, chlorine, bromine, iodine or fluorine, or with a solution of a salt of an alkali.
For the electrodes, I prefer to use soft iron for the positive electrode and hard pressed coke carbon for the negative electrode. The positive electrode is preferably a U-shaped bar of iron which has a circular cross-section. The two limbs of the U straddle the rod of carbon. Cast iron can be used but it gives a lower voltage, presumably due to the carbon and other impurities in it.
Magnesium gives excellent results, producing 2.25 volts per electrode pair where carbon is the negative electrode.
In implementing my invention, I level a piece of ground of sufficient area to contain the generating chain or chains. For instance, for three hundred positive elements each twenty inches (500 mm) long and two inches (50 mm) in diameter, bent as shown in Fig.3, the length of the piece of ground should be about 107 feet (32 metres) and 3 feet (1 metre) wide. I dig 43 holes at a distance of 30 inches (735 mm) apart (centre to centre) in a line. Each hole is 10 inches (250 mm) wide and 30 inches (750 mm) long and deep enough to contain the seven pairs of electrodes.
The loose soil dug from the holes is mixed with the chosen salt or acid in order to make the generator active. For instance, if the ground is a vegetable mould, then commercial concentrated nitric acid should be added in sufficient quantity to saturate the soil, and manganese peroxide or pyrolusite should be mixed with the mass. If the soil has a sandy character, then hydrochloric acid or sodium carbonate (“washing soda”) or potash can be used. If the coil is a clay, then hydrochloric or sulphuric acid and sodium chloride may be used, the salt being dissolved in water and poured into the hole before the acid is mingled with the soil. The bottom of the hole is moistened with water and the prepared soil mixed with water to the consistency of a thick paste is then placed in the hole, surrounding the electrodes. The 43 groups of electrodes when wired in series as shown in Fig.1, will yield 53.85 volts and 56 amps, developing a total of 3015 watts.
By increasing the number of cells, the capacity of the generator may be correspondingly increased to any desired power output. The prepared body of soil should be periodically moistened, preferably with the acid with which it was treated when first prepared for action. In a generator intended for continuous use, I prefer to provide a reservoir as shown as “A” in Fig.6, and run a pipe made of a material which is not attacked by the acid, along the chain of elements, with a nozzle over each element so that they all can be moistened very easily. Any accumulation of oxides or other products of the reaction between the prepared soil and the electrodes may be removed by raising the positive electrode and then forcing it back into place again. The carbon electrode can be cleansed by simply turning it without lifting it from its place.</font>
<font color=”blue”>I find that the period of use of the generator during which no addition of salt or acid is needed, increases with the period of use. For example, during the first day of use, the acid or salt should be added after 10 hours of use, after which it will yield 26 hours of service, and then after another moistening it will operate for 48 hours, and so on, progressively increasing in duration between being moistened. This generator operates very consistently and reliably.</font>
Nowadays, we find mains voltage alternating current to be the most convenient to use. For a system like this, we would be inclined to use an ordinary inverter which runs on twelve volts or twenty-four volts. However, it needs to be remembered that the working input current is high and so, the wire used to carry that current needs to be thick. At 12V, each kilowatt is a current of at least 84 amps. At 24V that current is 42 amps (the inverter itself is more expensive as fewer are bought). Considerable household usage can be had from a 1500 watt inverter.
The soft iron / carbon construction described by Michael Emme produces 54V from 43 sets of electrodes, indicating around 1.25V per set at high current draw. It seems reasonably likely that ten or eleven sets of electrodes would give around 12V at high current and three of those chains connected in parallel should be able to power a 1500 watt 12V inverter continuously at extremely low running cost.
Patrick Kelly
http://www.free-energy-info.com
http://www.free-energy-devices.com
http://www.free-energy-info.tuks.nl</font></font>
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Simple high power earth battery 1892 Michael Emme US495582 – example 3 KW array with 43 divots 10x15x15" – each 5" hole 15" deep produces 10 W (1.25V 8A) from Tesla
OP·2 yr. ago·edited 2 yr. ago
An earth battery is a very cheap type of chemical battery that’s constructed in the ground. It’s a lot like a potato battery. The power output is usually minuscule, but this patent describes a powerful earth battery. It says a single cell can produce 10 W with 15″ (38 cm) long electrodes. It appears to generate power by the electrolytic decomposition of the carbon electrode, but there could be more to it than that. It says any amount of power can be produced using only the ground, relatively cheap electrodes (iron and carbon) and electrolyte. It provides an example array to get 3 KW with 300 cells in 43 little trenches (10″ x 30″ wide, 15-16″ deep, spaced 30″ apart center to center), occupying a total area of 3′ x 150′ (1 x 45 m) to produce 54 V and 56 A (3 KW / 4 HP). Each little trench contains 7 cells arranged as shown in Fig. 1. Those example figures scale down to 1.25 V and 8 A per cell (10 W). That’s a lot of current.
The positive electrode is a U-shaped bar of iron made of 2″ diameter wrought iron (5 cm). The negative electrode is a 3″ diameter (7.6 cm) rod of pressed coke (carbon). The electrodes are inserted into the ground with the carbon rod straddled by the U-shaped bar as shown in Fig. 3. The loose soil from digging the holes is mixed with an electrolyte appropriate for the soil type and mixed with water into a paste which the holes are refilled with when the electrodes are placed. Cells in parallel can use the same hole like the example with 7 cells in each hole.
https://patents.google.com/patent/US495582
It doesn’t say how long the electrodes last, but they’re so big they probably last a number of years. I might guess 2-5 years and then maybe at least 5 years after that with much lower output. The iron is probably not intended to be electrolyzed, but that probably occurs. The output must decrease as the iron rusts. For maintenance, the U-shaped bar can be lifted and reinserted to wipe off any buildup. And turning the carbon electrode accomplishes the the same surface wipe. The iron electrode might be coated or plated with something to inhibit oxidation for greater longevity. Or other metals like zinc, aluminum or magnesium could be used for more power but shorter electrode life. Nickel should last a lot longer than iron. The electrode could be nickel or a stainless alloy, or it could be a coat or plating of nickel on iron. Unless the very large mass of iron does something with magnetism, it would be a lot cheaper and equally effective to use pipe instead of solid metal stock. By the time the pipe has rusted through, solid stock would be ready to recycle too.
It implies the need for additional electrolyte diminishes exponentially over time, but the example figures only go to four days. It doesn’t use the worst chemicals that are used in many batteries (like hexavalent chromium compounds that cause organ failure, cancer and birth defects), but the acid or salt electrolytes could easily ruin healthy soils. The electrolyte suggested for sandy soils, potassium carbonate, could be enriching at the right concentration. Maybe sandy soils are the best place for this, because the ideal electrolyte for that type of soil could have a beneficial effect on the soil. More environmentally friendly electrolytes could work in other soil types too with reduced power output, but the electrodes should last longer. The electrolyte supply could be something like the drain from a septic system (to the drain field), which is a constant supply of salts and acids that could act as a fair electrolyte that’s also good for soil. And the electrodes would last longer with the milder acid in that. There are other innocuous electrolytes that could be used. One natural electrolyte with much lower output is seawater. Then it’s called a sea battery. The output per cell electrode size is much lower, but with enough cells, any power is possible. If claims made in this 1979 patent are true, then even the largest ship could be powered by a galvanic sea battery. It contemplated building a 5 MW battery. This emits carbon mainly as carbonic acid in the soil. That might be sequestered near the source by plants like trees or cotton. Dumping a lot of salt and acid in soil can’t be good for the environment, but with the right considerations this could be very green. It seems like the cells should be covered to prevent evaporation because dampness is essential. That would reduce electrolyte use.
I can’t say if Tesla had anything to do with this particular earth battery, but the scale of the example (3 KW) is like him. While most earth batteries were only intended to produce small amounts of energy for telegraphy or little devices like a clock, Emme was using earth batteries for industrial power. Of course the grandiosity in saying an unlimited amount of power is obtainable is very much like him, especially in 1892. And finally, Nathan Stubblefield’s 1896 earth battery and ground telephony system suggest Tesla had investigated earth batteries extensively by that time. Stubblefield was one of the early inventors of surface wave conduction wireless. The idea was first patented in 1882 by Amos Dolbear, before Tesla, but it was apparently Tesla who insisted it was better than radio for the longer range, greater power transmission and lower ambient noise. And he inspired the others who used it after Hertz discovered radio waves in 1887. In 1902, Stubblefield said he started his experiments with earth batteries and ground current wireless in 1892. Tesla was probably interested in earth batteries as ground current power receivers in addition to using them for power.
Simple high power earth battery 1892 Michael Emme US495582 - example 3 KW array with 43 divots 10x15x15" - each 5" hole 15" deep produces 10 W (1.25V 8A)
by u/dalkon in Tesla