ENERGY: Present and Potential Sources

Comparisons of Gaseous Fuels

Note critical temperatures and pressures, esp 1st 3 fuels
Fuel**	Critical		Formula	___Per mole___			BTU per	vapor_pres
	oC	psi		gm	kcal	kJ	cuft	760 mm @
Natural gas*	-82.5	673
Hydrogen	-240	188	H2	2		285.8	319
Methane	-83	667	CH4	16	211	890.8	~950	-161.5oC
Ethane	+32	706	C2H6	30		1560.7	1700	-88.6oC
Propane	97	616	C3H8	44	526.3	2465
Butane	152	551	C4H10	58		2877.6	3200
*Per cent methane varies well by well, some are rich in propane; vehicles typically charged to 3000-3600 psi

**Handbook values are presented in a variety of units, so it is difficult to compare fuels in useful terms. I have undertaken some conversions for comparison. Conversion units are listed at the end of this essay.

Initially generation of electricity was direct current. Because of transmission (iR or current times electrical resistance) losses -- and power=current times voltage -- much greater power levels can be transmitted without significant power loss, by using transformers so transmission is at voltage levels of hundreds of kilovolts; thus alternating current has become dominant.

Of the two nuclear processes for the release of energy, fission and fusion, only fission has been controlled. In fission heavy radioactive atoms split to produce lighter atoms; in fusion light atoms join together to make heavier atoms. Both processes involve rearrangement of the constituent parts of atoms with the release of excess energy over that required for stability of the end products of the process. Our Sun is powered by fusion and research continues, in our laboratories, to contain the immense temperatures and pressures of the fusion process.

In common with coal- and oil-fired generation of electricity, heat from the reaction produces steam, which is used to drive the turbines that produce the electricity. Of course the steam could be used for motive power as in nuclear-powered submarines or aircraft carriers; in time it will undoubtedly be harnessed in trains.

Politics: Like so many scientific advances, war motivated progress. The public is well aware of the destructive potential of the atom bomb (a fission reaction), where primitive versions were exploded over Japan to end World War II, and experimental explosions of the vastly more powerful hydrogen bomb (a fusion reaction). After World War II scientific effort was dedicated to harnessing the immense potential for constructive purposes such as generation of electricity, and several processes were developed, each with its own safety requirements. And concern for public safety has driven politics.

Barring accidental releases of radioactive material from a nuclear reactor there are no local environmental degradation issues other than temperature increase in cooling water that is released into a waterway. Of course, the public is aware of the Chernobyl (Russia - 1986) and Three Mile Island (U.S. - 1979) incidents, which resulted from failure of control devices and a resultant melt-down of the radioactive core; it became obvious that initial design and construction must deal with the possibility of accident. In the Three Mile Island incident, there has been no reported leakage of radiation from the containment building or into the river; evidently design of that reactor facility was adequate. In the Chernobyl incident the immediate area is still a wasteland, some of it too 'hot' to allow tourists to visit; survivors have become the subjects of study on the effects of radiation poisoning.

We are continually bombarded with background (naturally occurring) radiation from both space (gamma radiation which produces nuclear events when it strikes molecules) and sub-surface (radon) sources. In evaluating radioactive leakage the concern is for increase in radiation beyond this natural background -- in the increases we can control -- rather than in total radiation. It is unfortunate that the public fear of accident and the resultant outcry against nuclear power generation has produced a near-hysteria and has curbed further research efforts. As various possibilities for problems became obvious, designs became more elaborate, resulting in the cost of nuclear power plant construction being so greatly increased by safety concerns that nuclear power is marginally uneconomical and initial investment has become a limiting factor in development of nuclear generation of electricity. (To my knowledge, no new installations have been undertaken in this country for years -- decades, in fact.)

There are concerns for public safety in three aspects of nuclear generation of electricity: (1) failure of a nuclear reactor that releases radioactive products into the environment, (2) accident in transporting hazardous wastes (by-products of nuclear reaction) through populated areas, and (3) long term storage of hazardous wastes since half-lives of some wastes are thousands of years and geological stability of storage sites is difficult to guarantee. Failure and construction costs are twin problems; hopefully new designs and new realizations will both reduce risk and lower costs. Accidents happen; containment vessels must be adequate to prevent rupture in all but the most grotesque accidents. Long term storage embraces several technical and scientific concerns, each of which can be addressed if there is will and foresight.

Disposal of radioactive wastes presents several challenges. Some concerns, such as protection of reprocessing and research personnel, are common to all. Processing spent fuel rods, which is the source of all concerns about waste, can separate non-radioactive from radioactive products. Researchers should strive to turn waste from one process into a resource for another. Many radioactive products have half-lives on an hour-days-weeks time scale; unfissioned radium and plutonium plus other heavy elements can be recycled back into new fuel rods; elements of intermediate half-lives may be irradiated in a nuclear reactor to transform them into non-radioactive or stable, non-toxic elements. Thus the volume of waste can be reduced by 95-99% and what remains may be encapsulated and stored; information available to me shows that encapsulated wastes -- and here we deal with isotopes (such as strontium-90, cesium-137, technetium-99 and iodine-129) one by one -- will decay and lose toxicity over the course of a few hundred years (rather than the many tens of thousands of years presently postulated). Wikipedia offers information on transmutation of nuclear wastes by either linear accelerator or sub-critical reactor so the bulk of waste has a remaining half life of less than 30 years.

I understand that, in the U.S., uranium ore is sufficiently plentiful there has been little incentive to extract uranium from spent fuel rods, so entire rods become waste. Were the uranium extracted from spent fuel rods, what remains may be treated as radioactive waste.

It is unfortunate that research in the U.S. on breeder reactor technology -- that is, generation of more fissionable material than is consumed in the course of expending fissionable material -- ceased. If power demands continue to escalate, nuclear will become a necessity, and breeder reactors will be a feature of the future. Simply put, if the United States does not maintain a lead in this technology, someone else will, to our probable disadvantage.

Technical: We are familiar with the orbital description of atoms, with electrons orbiting around a nucleus consisting of protons and neutrons and the number of electrons equal to the number of protons. Chemically, the number of electrons governs. Of course protons, being all positively charged, repel each other, so neutrons are necessary to prevent the nucleus from flying apart. And as the number of protons increases, there is an increasing possibility for extra neutrons, which gives rise to isotopes of the elements, such as carbon-12 (normal) with six each and carbon-14 with six protons and eight neutrons. And the nucleus of carbon-14 is unstable with a half-life of 5700 years, that is, in a sample of carbon-14 atoms, on average half will decay within 5700 years.

So we go on up the scale of elements through iron-56 (Fe₅₆) with 20 protons and 36 neutrons, through strontium-88 (Sr₈₈) with 38 protons and 50 neutrons to uranium-238 (U₂₃₈) with 92 protons and 146 neutrons and plutonium-242 (Pu₂₄₂) with 94 protons and 148 neutrons, the imbalance between protons and neutrons increases. As atomic weights (the '242' or '238') increase, fewer isotopes are stable although half lives may be exceeding long. The most common naturally-occurring isotope of uranium is U₂₃₈ (over 99%) with the remainder U₂₃₅, which is sufficiently unstable to be fissionable by ejection of an alpha particle (helium-4, with 2 protons and 2 neutrons). U₂₃₅ may fission to U₂₃₁ which may in turn fission to U₂₂₇, which may in turn fission to a lighter atom.

Thorium, with some help from traditional fissile materials, can set up a self-sustaining breeder reaction that produces U233, which can be used in power generation and is resistant to nuclear proliferation because of emission of enough gamma rays that the fuel is dangerous to handle and easy to track.

Ejected protons and neutrons may escape to the surrounding space and thus not participate in a chain reaction, but if they strike another atom, that atom may in turn eject a particle. When more particles escape than strike other atoms, the reaction is 'sub-critical' and no chain reaction occurs; if more particles strike other atoms than escape, the reaction is 'critical' and there is a chain reaction. In reactors for power production the degree of criticality is controlled by inserting or removing absorbing materials between fuel rods. However, other reactors may be designed for sub-critical operation so materials may be inserted to be bombarded by neutrons, thereby increasing the number of particles in their nuclei in order to create a heavier chemical and, depending on the stability of that nucleus, perhaps creating a different chemical.

We recognize the probability a spent fuel rod will contain a variety of chemicals and isotopes, including Pu₂₄₂ (U₂₃₈ absorbing one alpha). Exact mixture of isotopes will obviously depend on the energetics of the various reactions with nuclei in the fuel rod, which must depend on composition of the fuel rod and power level of reactor operation. For a light-water reactor, enrichment of U₂₃₈ with U₂₃₅ is only 3-5%; spent fuel rods contain about 94% uranium, 1% of transuranic elements (Plutonium and heavier) and fission products.

The uranium content of coal could produce more energy than combustion of the coal; yet it either goes up the smokestack or is dumped in a landfill as a constituent of ash.

COLD (nuclear) FUSION excited a great deal of public interest some years ago. It has been suggested that loading deuterium into palladium (by electrolysis) will produce the gas helium plus an excess of output energy over input energy. Development has been hindered by lack of federal interest and the apparent unwillingness of private sources to fund research. Graphs I have seen show insignificant power levels although there seems a modest amplification in power. Production of helium in the process suggests fusion is indeed occurring. The use of palladium, an extremely expensive precious metal, militates against widespread application; less expensive metals must be sought if there is to be hope for this technology. My personal estimate is that practical application is so far in the future as to be unworthy of heavy investment at this time, though a modest level of experimentation should be continued.

(There was a suggestion years ago that useful energy could be derived from a simple arrangement, using electrolysis of water in the presence of finely divided nickel. Demonstrations reportedly produced 1 kilowatt of heat energy for each 1 watt expended in operating the system, a multiplication of 1000. The author of this statement has offered no reference, and I have found none in following links at his web site. If such an experiment were successful I would think it would be a widely-used high school chemistry demonstration.)

Politics, July 2009 It is foolhardy in the extreme to think the Nuclear Nonproliferation Treaty will bar other governments from developing nuclear technology -- delay it, yes, but not prevent it. Aside from the U.S. and Russia, nuclear explosives are known to be in the hands of Israel, Pakistan, India and North Korea. One man, I think his name was Kahn, a native of Pakistan, was in possession of the knowledge and apparently sold it -- who knows where else? My personal suspicion is that nations other than Iran are currently surreptitiously developing their own nuclear technology.

Solar energy may be used directly as a heat source, or it may illuminate photovoltaic cells to generate electricity. Direct heating of a heat transfer liquid, which is used to produce steam to power generators, has taken two forms: 1) Extended lengths of tubing in reflective troughs that follow the sun are heated by direct sunlight, and 2) Reflectors, that follow the sun, direct sunlight onto a container of heat transfer liquid to raise its temperature. There are currently installations of both types but I am lacking in data; troughs produce elesctricity at $0.20-0.28 per kilowatt-hour. Photovoltaic generation currently costs $0.50-0.70 per kilowatt-hour.

Constancy is the greatest question to the user. The promise of solar energy is of course greatest nearer the equator (or between the Tropics of Cancer and Capricorn) and where clouds do not obscure the sun. And with ground-based collection, sufficient energy must be captured and stored during daylight hours to provide the needs of the overnight hours. In European installations huge arrays of solar panels produce megawatts of electric power. Every kilowatt-hour and every barrel of oil or cubic foot of gas that is saved is that much gain for the useful life of our resources.

It has been suggested that huge solar collectors in space could collect and concentrate solar energy and beam it to the ground. There may be promise in such technology, but we must be extraordinarily careful that the transmission of power to the ground does not sterilize the ground nor cook everything in the intervening atmosphere (including birds who may have a flyway during migrations).

In residential application, water heated by incident solar energy is an obvious application, especially since short term storage can overcome the irregularities in collection and usage. Home heating should be feasible in many regions; for comfort's sake it may be necessary to provide back-up equipment although some level of temperature discomfort during periods of extreme weather should be acceptable as a trade-off for conservation. On average about a quarter of the home energy budget is for hot water, with most of the rest for heating and cooling of the living space. I estimate that in most homes the cost of equipment for solar energy collection for hot water would be recovered in a year or two. I further estimate that, in using circulating hot water for space heating, solar energy could, in the northern United States, supply over 50% (and in the south over 90%) of total needed heat (with minimal auxiliary equipment for use in extreme weather). I have seen house designs for using solar heat only, using window location and massive walls (and other ballast) for heat collection and retention. (I am, in fact, surprised that federal subsidies have not been offered for retrofitting existing residences and for initial equipment in new housing.)

Commercial and industrial applications should not be overlooked. Certainly for hot water and heat in commercial buildings, solar energy should be part of their energy considerations. In industrial and commercial application it should not be a barrier to exploitation that there may be brief periods during the year when solar plus auxiliary heaters allows space heating to fall below ordinary comfort levels. In Spain it is now required by law that new buildings use solar energy for a portion of their needs.

And solar energy has been successfully applied to recovering potable drinking water -- and water for other home needs -- from the ocean on a commercial scale. It dumbfounds me that local solar distillation has not been massively applied in the Third World and in areas with adequate but contaminated water.

In Spain new commercial buildings are required to use solar energy for a high percentage -- wish I had kept the reference -- of their energy requirement.

A solar chimney is planned in Australia where a chimney some 0.4 miles high will be heated by the sun and rising air trapped within will drive turbines.

To deal arithmetically with solar energy, we measure a solar constant (amount of energy received atop Earth's atmosphere on a square meter that is normal to the sun) at Earth's average distance from the sun. It is about 1.3 kilowatts with a variation of some 2% due to solar activity. As the sunlight penetrates our atmosphere, some 20% is absorbed by atmospheric constituents and some 30% is reflected from clouds, aerosols, glaciers, water, sand, vegetation, etc. (not as infrared energy but at the same wavelengths as are incident). So some half reaches the ground and is absorbed there. Of this half some 40% rises into the atmosphere as water vapor (including the heat of vaporization) and convection currents; the balance heats Earth and the warmer Earth radiates energy into the atmosphere as infrared energy, some of which penetrates to space while some is absorbed and heats certain atmospheric constituents (the so-called "greenhouse gases"). Of this absorbed heat about half is reradiated into space and the other half is reradiated to the ground, raising ground temperature further. A temperature balance (or, more accurately, a balance of energy flows) is reached between incoming and outgoing radiation.

The effect of solar radiation on any specific unit of Earth's surface varies according to angle with incident radiation, distance energy travels through the atmosphere, intervening clouds, and the radiative nature of the surface (both reflective, absorptive and reradiative). Evidently, numbers describing local reception of solar energy are highly dependent on local conditions so averages for Earth are not predictive of local reception. It is estimated that, on average, 240 watts reaches every square meter of surface.

I had at one time wanted to pursue application of solar energy to distilling ethanol from fermented vegetables. It was not at the time interest in economy but interest in technology because vacuum distillation would be involved and my specialty had been vacuum technology; I did not pursue it.

8-18-05 From a report dated in 1997: Solar cells of polycrystalline silicon of 12-15% efficiency are on the market with promise of 18% upon removal of impurities. Photovoltaic cells vary in response to wavelengths of incident radiation; maximum theoretical efficiency of conversion has been estimated at more than 70% using the entire spectrum, which would require multi-layer construction, while a two-layer cell may reach 50% conversion efficiency. It is estimated that an efficiency of 14% is the boundary for commercial competitiveness. 12-12-05 Researchers at Ohio State University claim 97% capture of the solar spectrum in solar cells designed for satellite experiments. OSU researchers also have produced a hybrid material capabale of capturing the entire energy content of sunlight. 11-6-08 Researchers at Renssalaer have developed a reflective coating that makes possible collection of energy without repositioning the array as the day advances.

A fascinating statistic: A typical coal-fired generating plant consuming 10K tons of coal per day is liberating 100 kg of uranium per day, either up the smokestack or in the ash that is dumped into a landfill. The energy content of the uranium in the coal is greater than the energy yielded by burning the coal.

Atmospheric consequence: Coal is pure carbon plus impurities; burning it produces CO₂ plus compounds of the impurities, such as sulfur dioxide (SO₂), which combines with water in the air to produce sulfurous or sulfuric acid which may in turn decompose to aerosols.

Like solar energy, constancy is an essential concern. There are localities with prevailing winds of a constancy and velocity where turbines may be used to generate electricity on a competitive basis. Where there is sufficient wind to power industry, there seems the possibility of suspending industrial output during periods of calm so extended as to exceed the limits of energy storage (batteries). While I cannot foresee a likelihood that whole communities could be developed with the possibility of extended discomfort, I can see a local dual-energy economy with wind as a primary energy source with only nominal back-up, perhaps solar, for home heating and hot water.

I have not followed the installation of wind farms on the Oregon coast for the generation of electricity, but I am heartened at efforts to tame the winds. But I have recently read (National Geographic, Aug. '05) that wind turbines are generating significant quantities of electricity, in Denmark some 20% of the nation's needs, significant installations in Germany and some in Britain. A web search reveals the competitive nature of a developing technology and useful general information is difficult to find. There are maps of wind velocities at various heights above ground although wind is highly localized and strongest on mountain ridges. New Hampshire's White Mountains has reportedly the highest velocities in this country, and such locations as the Himalayan mountains should hold possibilities for exploitation although transportation would become a question. (I can visualize whole nations being supported -- as in the case of petroleum -- by production of electricity by mountain winds.)

A Dutch firm has anchored a wind turbine off the coast of Italy, expecting to generate nearly 10 megawatts per turbine.

FloDesign Wind, a domestic start-up company is preparing to test wind turbines 60 feet in diameter based on jet engine designs (instead of propellers some 150 feet long). Whereas many propeller designs generate 1-2 megawatts per unit, their design is expected to generate 250 kilowatts per unit. In a wind farm, units may be spaced much closer than propeller turbines.

Automobile makers are seeking lithion-ion batteries that will endure 15 years and 5000 charging cycles and store enough energy to drive a car 40 miles. Stationery batteries have been used to augment solar heat although it is quite expensive.

HYDROELECTRIC

Atmospheric consequence: Methane is produced by the anaerobic decay of plants and stumps submerged in creating the dam, and methane is 21 times as powerful in the greenhouse effect as CO₂. On balance a dam may produce as much atmospheric consequence as burning the fossil fuel it replaces.

Levies on the Mississippi have demonstrated that Nature will work its way and that there are practical limits on man's ability to control Nature.

Tides have also been harnessed in locations where it was economically advantageous to do so. A wave generator is being developed at England's cliffs to convert the ocean's wave motion into electricity. A number of patents have been filed for various devices to use wave motion to generate electricity, and other developments are presently under way.
Off Oregon's coast a wave generator is planned to supply 400 homes. Cost $4 million. It is some 150 feet tall, 40 feet wide and weighs 200 tons. Others are planned but there are skeptics.

Research in the Netherlands uses ion exchange membranes where fresh water and sea water come together. Alternating membranes have river water between +-- pairs and sea water between --+ pairs, each pair producing a voltage difference. The Dutch reportedly expect to generate 300 MW at a single site.

BIOMASS: Wood and Wastes (including agricultural)

Oak 3.99 kcal/gm; pine 4.42

Conversion of biomass into various fuels depends on the temperature to which the biomass is initially exposed.

There is tremendous waste of combustible wood, such as roadside burning of trees felled for highway development. Or of trees cut for beautification or for safety reasons. And clear-cutting of forests for agricultural land. I am unaware of any organized effort to collect these (otherwise waste) woods for use in electricity generation or other energy applications -- not even for home fireplaces. I am unaware how wood chips, produced for tree management or clean-up of storm debris, are disposed of.

The National Bioenergy Center is testing various organisms that can digest woody cellulose to produce methane or methanol. And it is claimed that switchgrass, native to the American prairies and presently used for animal food, if converted to methanol could produce 1/2 to 2/3 of demand for U.S. transportation fuel.

Despite their ubiquity I do not see the collection and burning of leaves and pine straw as commercially viable energy businesses or fuel choices although it may be possible to ferment either to produce alcohol. Where household organic wastes are composted as a means of waste disposal, should the heat generated find useful application, then organized collection of leaves, straw and yard waste could become justifiable.

I have learned of two landfills in the State of Georgia where the methane produced by (anaerobic) decomposition of waste is captured and used to generate electricity. A sketch of one installation shows a liner underneath waste and a cover of dirt, with wells used to collect the gas. (Landfills emit some 34% of the methane released into the atmosphere.)

In my own practice I am composting leaves and lawn clippings. This should provide fertilizer for what gardening efforts I undertake.

I recall there was at one time talk of collecting hyacinth from northeast Florida waterways for use as fuel. This as a means of controlling unwanted vegetation in navigable waterways; use as fuel was incidental.

A study of 62 kinds of biomass in 1985 reported 17.5-18.75 mJ/kg for corn, 13.75 for weathered rice star (straw?) and 23.28 for prune pits. That equates to 4.3, 3.3 and 5.6 kcal/gm, respectively. One estimate is that, should biomass become the principal transportation fuel source, it would require doubling the amount of land committed to agriculture. (See comments on seed oils.) Another estimate, in 2009, suggests that 1/2 of domestic transportation fuel can be derived without any demands whatever on food production.

Raw sewage is being used in some parts of the world as a combination of fertilizer and water for crops.

ANIMAL FATS

Manufacturing plants are currently on line to produce the equivalent of crude oil from agricultural waste such as waste from a turkey processing facility.

GEOTHERMAL

Heat is brought to the surface by a heat transfer liquid, which heats water to produce steam to generate electricity. Cost per kilowatt-hour is $0.06-0.076. Geothermal enjoys the advantage that it produces electricity around the clock as demand varies.

There are applications aplenty in regions where volcanic heat lies just below the surface and has been used as an apparently inexhaustible source of heat. And there is no doubt that, with some innovation, volcanic heat may be tapped, in selected locations, at increasing depths.

GROUND HEAT

I have just learned (Jan 07) of heat pump applications of commercial and industrial size using loops of buried liquid (antifreeze)-carrying tubing to use ground heat for both heating and cooling. Electric energy cost has been determined to be half to a third that of conventional petro heat, with no other fuel required.

Undoubtedly homes of the future will take advantage of ground heat, with sub-surface temperatures near 55^oF throughout the year. A home partially submerged, and using the displaced earth for thermal insulation, would need only nominal energy to increase its internal temperature 10-15^oF, well within the bounds available from ground-level solar collectors or collection of ground heat.

The mountain home I did not build contemplated using a subterranean tunnel for air entry over heat transfer surfaces using ground heat for cooling and heating, with supplemental heat. I never got around to designing the heat exchange device for rejecting heat to that immense underground heat sink but did contemplate something akin to a septic tank leach field. Due to low thermal conductivity of soil, collection surface area would be large.

COMPRESSED AIR

VENTILATION

Obviously if air is to be drawn in from outdoors there must be ports for both entry and exhaust.

At one time our home used a large exhaust fan, primarily in lieu of air conditioning in the summer but occasionally for heating when indoor and outdoor temperature conditions allowed. It required operator intervention in selecting the times when it would be cost effective and in opening windows or other inlets; of course the process could have been automated but we did not undertake controls beyond on-off and opening selected windows. This seems a fertile application for home computers and "smart homes" as the products of the digital revolution become more widespread.

Automatic ventilation of attics to retard penetration of heat collected by the roof has long been common.

Ultimately nearly all the energy available to us comes from the sun and is, after taking part in various energy interchanges, radiated into space. A simple calculation equating energy received from the sun with radiation into space (by the fourth-power law) yields an average world-wide temperature of 0^oF. (I won't get into computation of world-wide average; that is a study unto itself.) The measured average is 59^oF. Over geologic time it is estimated that changes producing ice ages were less than 5^oF, a small change for such a significant result. The only reason that can be postulated for the difference between the theoretical average of 0^o and the measured 59^o is trapping heat in Earth's atmosphere and its reradiation to the ground before ultimately escaping into space. So there is a natural greenhouse effect that has made Earth habitable.

Each gas and each kind of particulate matter in the air makes its contribution to the greenhouse effect, nitrogen and oxygen essentially none, water vapor, methane and carbon dioxide being the principal contributors to trapping heat (water vapor on a short time cycle, methane on an intermediate time cycle and carbon dioxide on a time cycle of many decades. Carbon dioxide concentration in the atmosphere was measured at 270 parts per million in the year 1750 and is some 350 now; and presumably the increase is primarily the result of the activities of our species. Scientists have undertaken to learn the carbon cycles worldwide -- the sources of carbon such as carbon dioxide and the sinks where it is removed from the atmosphere and bound up in vegetable matter, etc. This information is far from complete, but it is obvious that massive reductions in rain forest and destruction of kelp beds removes substantial sinks and may be a major contributor to the rise in atmospheric carbon dioxide. It is the increase in atmospheric carbon dioxide (and to a lesser extent methane) that causes environmentalists such concern about a generally increasing average temperature of Earth.

Sequestration of CO₂ from electricity generation is accomplished by combining the CO₂ with the mineral serpentine to produce magnesium carbonate, which is then used in place of limestone in the manufacture of cement.

Definitions, formulas and conversion factors: (Values cited are for the most part handbook values.)
In the international scheme, energy (or work or heat) is measured in joules (J) and power is measured in watts (W). Both units being small, it is easier in practice to use the prefix "kilo (k)," which is 1000 times larger. As a unit of energy the calorie (cal) has been so widely used that it is included (as kcal).
Power is the rate at which energy is expended, so energy is power expended multiplied by duration of its expenditure.
Arithmetically, anything multiplied or divided by unity (or 1) is unchanged. To use these conversions, make a fraction of two equal values (carrying along the units); multiply the quantity being converted by that fraction, cancelling units to be sure you have an accurate conversion
1 kJ = 1 kW-sec = 0.948 BTU = 0.239 kcal
1 kW = 1 kJ/sec = 1.341 hp = 293 BTU/hr = 0.239 kcal/sec
1 kcal = 3.967 BTU = 4.186 kJ = 0.001163 kW-hr
1 kW-hr = 3412 BTU = 3600 kW-sec
1 liter = 1.057 qt = 0.264 gal = 0.0284 bu, or 1 gal = 3.788 liters = 0.1337 cuft = 0.1076 bu
1 cuft = 7.481 gal or 1 cu m = 1000 liters
1 lb = 454 g or 1 kg = 2.203 lb
1 mi = 1.609 km or 1 in = 2.54 cm or 1 m = 39.37 in
1 acre = 0.4047 hectare (ha)
1 quad = 10¹⁵ BTU
Specific gravity (SpGr) is the ratio of weight of a liquid to that of water, measured at one temperature but reported at a reference temperature. Water at 15^oC of 8.328 lb/gal is taken as reference. SpGr times density of water yields density of the liquid. Thus SpGr(X^o/15^oC) times 8.328(15^oC) yields weight per gallon in pounds of the liquid at 15^oC.
Mole: For each element in the formula, multiply its atomic weight by the number of atoms in the formula; add them together. That number of grams is one gram-mole; and that number of pounds is one lb-mole.
STP: Standard Temperature and Pressure: At a temperature of the ice point of water (0^oC) and a pressure of 1 atm (14.7 psi)
A perfect gas at STP occupies 22.4 liters per gram-mole. While few gases are perfect near their boiling points, it is a useful approximation and, well above the boiling point is quite correct.
Absolute temperatures: To degrees Fahrenheit add 460 to get degrees Rankin. To degrees Celsius (or Centigrade) add 273 to get degrees Kelvin.
Critical temperature: The temperture above which a gas cannot be liquified regardless of pressure
Critical pressure: Equilibrium pressure at critical temperature so gas and liquid can coexist; at lower pressure it cannot exist as a liquid
Critical temperature and pressure: For the gas to exist in the liquid state, it must be at a temperature below critical and a pressure above critical.
A quad is short for 'quadrillion BTUs,' or 10¹⁵ BTUs.
Temperature is related to mass and velocity of constituent molecules 1/2 mv². In solids the movement of molecules is contrained; in liquids molecules are free to glide past one another; in gases each molecule moves in a straight line until it collides with another molecule. In compressed substances such as our atmosphere energy transfer between molecules results in a common temperature. In rarefied gases such as our upper atmosphere, temperature of a molecule may be as high as 3000^oF but the reading on a measuring device (such as your skin) it would be cold due to the low frequency of collisions with the device.