Category Archives: General Science

It’s About Time

Weights and measures including time, are immeasurably important to to our lives. Our food supply our depends on our knowledge of the seasons, and what we buy and sell is linked to our ability to measure what something weights, or its volume and myriad of other measures.

Measure of time comes in two ways, that set by some natural phenomena such as the time it takes the earth to travel around the sun and those times which are seemingly arbitrary – the length of a second, a minute and an hour.

The length a year is obvious, it is how long it takes the earth to circle the sun, about three hundred sixty five days. But not exactly because it is actually about a quarter of a day longer, hence the need for leap years which have three hundred sixty six days. There is actually another finer adjustment, because to keep the calendar in sync with the season, there is one more rule, a century year is not a leap year unless it is evenly divisible by four hundred. The year two thousand was but the next three century years will not be.

Winter soltice, Machu Pichu

Winter soltice, Machu Pichu

A day is governed by the time it takes the earth to rotate on its axis. The time it takes to make a full rotation is actually lengthening due to tidal forces which create drag and slow the rotation but not by much. A day gets a tiny fraction of a second longer in a century.

When we start carving up a day we move into arbitrary units. Why twenty four hours in a day, sixty minutes in an hour and sixty seconds in a minute? The twenty four hour day has as its origin the observations of stars by the ancient Egyptians. This has little to nothing to do with modern time keeping, but it stuck. The same is true for the divisions of hours and minutes. In this case we look to the Babylonians who had a base sixty counting system. To the Babylonians numbers like six, twelve, sixty, and three hundred sixty were “round numbers” just like ten, one hundred, and one thousand are round numbers in our base ten decimal system.

Talk about stuck in a rut, we measure time based on an archaic, four thousand year old, base sixty system which is confusing and unnecessary.

Big Ben

Big Ben

Quick, tell me how many seconds in three hours. UGH – let’s see sixty times sixty times three. Like archaic measurements used in the United States, bushels and pecks, ounces and gallons, and ounces and pounds, these non-decimal calculations are tedious.

Scientist use the metric system for its simplicity. Virtually all units are in base ten EXCEPT
time. It’s about time for a change. The staff at “Keep Time-keeping Simple Inc” Propose the following: ten hour days, one hundred minute hours and one hundred second minutes. If you were keeping time with a one mississippi, two mississippi kind of notation it would work for decimal time, as doing the math shows the decimal second to be eighty six per cent as long as a Babylonian second.

Back to the previous challenge of how many seconds in three hours, no problem: one hundred times one hundred times three is thirty thousand. You can do it without pencil and paper.

Lunch is at five o’clock sharp, and if you don’t want to stay up for Johnny Carson, set the VCR to record at 9.375 and don’t worry about AM or PM, they don’t exist. Good night everybody

high speed rail

Trains, Here and There

Automobile use as measured by miles traveled per capita peaked in 2005 and has been falling since. It is had to explain by a single variable, gas prices have been both up and down, not continuously up. We went through the worst recession since the great depression, but the economy is now improving, albeit slowly. Vehicles are becoming smaller so less accommodating for passengers but more efficient thus cheaper to operate.

Regardless of the reason, we are moving around less; and, there has not been a concomitant increase in mass transit. Is it time for us here in the US to consider an emphasis on mass transit to the degree that is available in Europe or the far east? Travel by train there is easy and frequent. You want to go from Edinburgh, Scotland to Bucharest, Romania, 1700 miles? There are trains for that, and daily I might add.

Not only can one travel long distances between large cities, but also short distances to small towns as well. There are nine different departure times daily from Chepstow, Wales to London, England (Chepstow is a town about the size of Clarksville, AR.) This would be equivalent to a train, nine times a day from Clarksville to Little Rock.

But we’re all about speed, right; and trains are too slow. Well they’re not so slow in Europe or the far East. Speeds between one and two hundred miles per hour are common.

European high speed rail

European high speed rail

And unlike the USA; Japan, Korea, and China are all investing in infrastructure which will allow for faster, more efficient trains.

China currently operates a fourteen hundred mile rail at over two hundred miles an hour, and is expanding rail service faster than highways or airlines. When a high speed rail became available in Taiwan most passengers switched from the comparable air route, and highway congestion decreased.

Technological advances in Japan involve a Maglev train. Maglev is short for magnetic levitation, where levitation of the train above the rails means a near frictionless and therefore faster, quieter and more efficient rail line. The train has been successfully tested on a short track at over three hundred miles an hour and expects to be in service by 2015.

What about American Exceptionalism? Is anything unique going on here? One bright spot is California which has proposed a high speed rail line between Los Angles and San Francisco. The voters in California have approved close to ten billion dollars to develop the line, which at two hundred miles an hour would complete the trip in two to three hours. Current driving time for the trip is seven or eight hours.

A real game changer has been proposed by entrepreneur Elon Musk, who designed and sells the Tesla, a successful all-electric car. He wants to build a Hyperloop, basically an evacuated tube,

hyperloop

hyperloop

to transport people at eight hundred miles per hour. The technology is the same as that used to move money and checks from the remote teller to your car at the bank. The trip from Los Angles to San Francisco would be about a half an hour and if similar technology existed locally one could go from Little Rock to Dallas in about twenty minutes. Now that would be both exceptional and American.

poison ivy

Poison Ivy

The old adage “leaves of three, let it be” helps to identify and therefore avoid poison ivy. The plant is polymorphic, growing as ground cover, small shrubs up to two or three feet high, or a climbing vine. It is often confused with virginia creeper which has five leaves. Formally named Toxicodendron radicans, it and other related plants contain urushiol (oo-rush-ee-ol) . The substance is present in all parts of the plant; leaves, stems, roots, and berries. Poison ivy, poison oak, and poison sumac are known to cause the characteristic itchy, blistering rash.

Virginia-Creeper

Virginia-Creeper

Other plants such as cashews also have urushiol when raw and must be properly processed, shelled and roasted, to remove the plant oil. Lacquer, the stuff that produces the beautiful shiny finish in furniture, contains small amounts of urushiol and can affect hypersensitive individuals. The name urushiol comes from the Japanese name for Lacquer, urushi.

The first time, or first few times one is exposed there usually isn’t a reaction. Only after being exposed does one become sensitized and on second exposure develop the itchy rash. This is because urushiol is an allergen, something which causes an allergic reaction , and and the allergy has to be “learned” by exposure.

Actually it is a bit more complex. Only proteins, very large molecules, can cause an allergic reaction. Much of our bodies are protein so our immune system must be able to distinguish our proteins and foreign proteins. Antibodies develop as a method to rid the body of foreign protein. A whole cascade of chemical reactions occur once the immune system identifies a foreign protein. Urushiol is not a protein but a substance know as a hapten. Haptens are small molecules which can chemically react with protein. Once a protein, for example the keratin of our skin, has reacted reacted with urushiol our bodies no longer recognize the protein as “self” but rather as foreign.

Urushiol is a fat soluble oleoresin, which means that it can penetrate the skin within an hour or two. There it reacts, “labels” the protein, and sets the allergic reaction in motion, the rash occurring several hours after exposure. Heavier exposures result in a faster reaction.

This has lead to the misconception that the allergen may be carried through the blood. For example heavy exposure to the back of the hand and only slight exposure to the upper arm means that the rash will show up on the hand first and arm only later.

Another misconception is that the fluid present in the blisters contains the poison. Once the blisters form, the poison is long gone. You can’t get a reaction just by coming in contact with someone else’s rash. You can be exposed by secondary contact however. There is a fairly wide variation is sensitivity so exposure and subsequent reaction can occur when a sensitive person handles the clothes of a less sensitive person.

In extreme cases, people are exposed by inhaling smoke particulates from burning poison ivy. This can be dangerous as the rash occurs in the throat and even in the lungs.

Geothermal Heat Pumps

The term geothermal when applied to heat pump technology means that the ground is used as a heat exchange medium, rather than the air. Heat pumps are nothing more than reversible devices to heat and cool a home.

The technology is the same as refrigeration. When a gas expands, it absorbs energy from the air, thus cooling the surroundings. Refrigeration works by using a pump to compress a gas, called the working fluid. The compressed gas, now a fluid, is moved to the area to be cooled and then allowed to expand. The heat being moved by a heat pump is expelled away from the area to be cooled. For most systems, “away” is the air outside the house.

The hotter it is outside in the summer, the harder a heat pump has to work to cool your home. This is where the ground comes into play. Geothermal heat pumps use the ground as “away”. The heat exchanger portion of a geothermal heat pump is connected via wells drilled or lateral lines on the property to water or some other liquid which transfers the heat to the much cooler ground, rather than the much warmer air. This process is more efficient at moving heat, and therefore summer cooling costs are lower.

The process is reversed in the winter. Compressing a gas inside a home produces heat, then the compressed gas is moved out of doors and allowed to expand and cool out of doors. Heat pumps are quite efficient at heating in the winter as long as the temperature is not too low. The colder it gets the less efficient the system. For a geothermal heat pump, it doesn’t matter what the air temperature is because the heat exchange is with the ground which is about fifty to sixty degrees Fahrenheit year round. In the winter the ground is warmer than the air so geothermal heat pumps are more effective than traditional air source systems.

Overall geothermal heat pumps are more efficient than normal air source heat pumps, particularly during the temperature extremes of summer and winter. In a study at Fort Polk Louisiana, heating costs during winter days below freezing were forty per cent lower. During the summer days with the temperature over ninety degrees, the costs of cooling were also about forty percent lower with the ground source heat pumps compared to air source heat pumps.

Heat pumps work best when the difference between the outside and inside temperatures are not great. Geothermal heat pumps take advantage of the more stable ground temperature, keeping the difference lower than for air source heat pumps.geothermal_heat_pump2

ground-source-heat-pump3

Geothermal systems require the drilling of wells or laying lateral lines to create the ground contact so the systems are inherently more expensive that simple air source systems, but because of their greater efficiency, usually have payback periods on the order of five to ten years.

Geothermal Energy

The term geothermal has come to be associated with two technologies which are only tangentially related; first, power can be produced by drilling into the ground to a depth where the rock is hot enough to boil water. The other use of the term geothermal is associated with ground source heat pumps which need only drill down a few feet to a temperature of fifty to sixty degrees Fahrenheit.
 
Utility scale power can be produced by drilling into the ground to a depth where the rock is hot enough to boil water to produce steam. The steam is then used to drive a turbine to generate electricity just as a nuclear reactor or a coal fired power plant produces steam to turn turbines. Electricity production from geothermal heat requires drilling several kilometers into the earth and is consequently very expensive, but in certain locations heat is near enough to the surface to make its utilization practical.
 
Heat at the core of the earth is approximately 6000 degrees Celsius, hence a temperature gradient exists: twenty five degrees C per kilometer. The heat is due to at least two factors, residual heat from the accretion of the planet over four billion years ago and radioactive decay of certain elements such as Uranium and Thorium.
 
To economically produce power, hot rock must be within three or four kilometers of the surface. This only occurs in geologically active regions, such as areas with earthquakes and/or volcanoes. In these locations fissures in the earth’s crust allow movement of magma near enough to the surface to be exploited for power production.
 
The simplest design for a geothermal power plant takes advantage of hydrothermal convection. Cool water from the surface seeps underground, is heated and then rises back to the surface. The heated water, now steam, is obtained by drilling wells to capture the steam and directing it to turbines for energy production. The water from the condensed steam can then returned to continue the cycle.
 
Although the heat is essentially free, the cost of drilling and maintenance of equipment can be high. Subterranean steam extracts caustic materials which corrode even the most inert metals. A limiting factor for energy production can be the rate of heat transfer through rock. As heat is extracted from rock surrounding the well site, heat must be transferred through the rock, limiting the rate of heat extraction.
 
The United States leads the world in geothermal electric capacity. The US has about 2.7 GigaWatts installed, a quarter of world capacity. Twenty six plants in one location called the geysers,

geysers north of San Francisco, accounts for three quarters of the total US production. For comparison, one nuclear reactor has a capacity of just under one GW.
 
Parts of Alaska, Washington, Oregon, California, and much of Nevada and Hawaii have potential for geothermal electricity production and much of the Rocky Mountain area could extract useful heat for direct uses such as space heat for apartment buildings, schools, and other large facilities.

The Anthropocene

Scientists in general and particularly geologists measure time on our planet in epochs. For example the time from two and a half million years ago until twelve thousand years ago is called the Pleistocene. This time period was characterized by a series of long glacial periods. The current epoch is called the Holocene which began with the worldwide recession of the glaciers.

Recently some scientists have called for the naming of a new epoch called the Anthropocene, characterized by human influence on the planet due to our transformation of the atmosphere over the last two hundred years. Others contend that the start of the Anthropocene should be counted as starting much earlier. Modern humans have influenced the planet by churning the biosphere for close to a hundred thousand years. Our mobility has resulted in the movement, occasionally purposely, of many many plants and animals.

Wheat originated in Near East, corn in Central America, and rice in Far East. All are purposely cultivated world wide. The inadvertent introduction of some species has been the ruination of others. The inadvertent human dispersion of the black rat is a good example. It has caused the extinction of many bird, reptile, and other small vertebrate species across the planet.

The honey bee originated in Africa, and migrated to Europe. It was brought to North America by the colonists for honey production and has been a resounding success. Annually fourteen billion dollars worth of crops are dependent on honeybee pollinationhoneybee in the United States alone. Ironically the honeybee brought to North America by humans is now threatened by humans by the use of a class of insecticides known as neonicotionoids.

Non native earthworms were also brought to North America by the colonists but this time the importation was accidental. They came as part of the ballast of ships and in the soil of potted plants. Their introduction has been a mixed bag. Whereas home gardeners and those who fish extol the virtue of the earthworm, they are actually harmful to forests of northern North America.

Glaciers advanced to about the Missouri and Ohio Rivers and wiped out earthworms, if there were any to begin with. After the glacial recession, the forests returned and adapted in the absence of earthworms. The normal condition of the forest floor is a thick layer of slowly decomposing leaves. The presence of earthwormsearthworm accelerates this decay, removing an important organic layer that serves as seed beds for saplings, ferns, and wildflowers.

One of the newest accidental imports is another ant, called the Crazy AntCRAZY ANT for its erratic behavior and tendency to swarm. It first showed up in Houston TX and has been seen in southeast TX, southern Louisiana, southern Mississippi and and much of Florida. Where it occurs it either kills or drives out most other species of insects, spiders, small reptiles and birds. They will nest just about anywhere but are particularly fond of electrical wiring, causing a 150 million dollars a year damage in Texas alone.

We certainly live in a time of dramatic global human influence. We continue to change the composition of the atmosphere and hence the climate. We are making the oceans more acidic. We are dispersing uncountable numbers of species, generally with negative impact. And all these effects are causing extinctions of flora and fauna. My question for you is should we?

Carbon Capture and Storage

President Obama recently gave a speech at Georgetown University addressing global warming. He has recognized that limiting carbon emissions from power plants is an important step in reducing our contribution to the release of green house gases. One approach is the process where the Carbon Dioxide produced by burning fossil fuels such as coal is captured and stored, rather than released to the atmosphere.
 
If Carbon Capture and Storage (CCS) can be made to work, we could have our cake and eat it too.  That is, we could have the benefits of cheap energy without the negative consequences.   Basically CCS is a process of capturing the Carbon Dioxide waste stream from a power plant and then putting it somewhere other than the atmosphere.

The problem is that it is neither cheap nor easy. CCS technology could double the construction and operating costs of a power plant.   A further limitation is the need for storage sites such as airtight underground caverns or the ocean depths, where the carbon dioxide would stay for a long, long time. Like forever.
 
The best site would be a geologic formation where subsurface rock naturally reacts with carbon dioxide via a process which chemically mineralizes it. These formations exist but are few and far between. We need enough storage space for about thirty billion tonnes of carbon dioxide for this year and even more in future years due to growth.
 
Without mineralization, storage becomes much more difficult. Carbon dioxide, a gas at normal pressure, would need to be pumped into storage wells and the wells then capped to prevent release.  At atmospheric pressure it would require over six thousand cubic miles of underground open space per year. This kind of space doesn’t realistically exist, hence pressurization is necessary to reduce the volume.   The higher the pressure the more difficult it will be to contain the stored gas. Any leakage will increase the cost both economically and energetically- all that capture, transportation, and pressurization uses energy.
 
Another storage site to consider is the ocean depths.  The advantage of ocean storage is that the conditions of the abyssal plain are high pressure and low temperature.  Under these conditions carbon dioxide exists as a liquid with a volume only a fraction of that as a gas.   Slowly, the dissolved carbon dioxide would react with seawater forming carbonic acid. We would slowly turn the oceans of the world into salty soda water.  Rather than just sounding silly, it’s actually deadly.  The acidity created by the higher carbonic acid concentration would essentially sterilize the oceans.
 
The only way to store the thirty billion tonnes of carbon dioxide produced every year seems to be by pumping it at high pressure into every hole in the ground that we can find, plugging the hole and then hoping that the cap doesn’t come off, forever.  But what if a storage site does burp?
 
Lake Nyos is a crater lake in Africa.  Local conditions cause the lake to be supersaturated with carbon dioxide.  A limnic eruption occurred in 1986 for causes not entirely clear.240px-Nyos_Lake This event caused the near instantaneous release of close to 2 million tonnes of carbon dioxide. This is just like the classic mentos and diet coke eruptions, except deadly. The heavier-than-air gas killed about 1700 people and all their livestock.  This area was thinly populated or the death toll would have been much higher.
 
Carbon capture and storage, in the last analysis, is expensive, uses a lot of energy, and is quite risky to all life in the area of the storage wells.  Additionally Carbon Dioxide is only about half of the problem associated with global warming. The only real solution is abandon the use of fossil fuels and get all our energy from wind, solar and geothermal.

Biofuel is Inefficient

The United States attained the position of a superpower to a very large degree by our ability to utilize fossil fuels. Our way of life requires burning massive amounts of those fossil fuels. The wastes released by burning these fuels is leading to global warming and ocean acidification. If we want to preserve any semblance of a natural environment on this planet we must stop.

To maintain our lifestyle we have to adopt energy production systems that are free from carbon pollution and have long term sustainability. Direct solar, wind, and biofuels derived from crops are three strategies being exploited on a small scale already.

These three energy sources all derive from the sun but are they of equal efficiency? The short answer is NO, in capital letters. Not only are biofuels very inefficient in terms of land use, but also compete with food crops for acreage, fertilizer, and water.

Although the direct tax credits for biofuels like Ethanol and Biodiesel have been discontinued, we continue to subsidize these energy sources by crop price supports and mandates for biofuel use. This is certainly good for agribusiness, but is it good for society?

Consider the productivity of Ethanol from corn. In the United States, we use about half the corn we grow for ethanol production, roughly 50 million acres per year. For this we get 3 billion gallons of gasoline equivalent from ethanol. The problem is that we use over 130 billion gallons of gasoline a year. If we put every arable acre of land in the country in corn (580 million acres), we still would only be able to produce less than half of the fuel we need.

And we would have nothing to eat! The problem with biofuel is that photosynthetic efficiency is very low. That’s why it took hundreds of millions of years to accumulate the fossil fuels were are now consuming.

Of course, there are alternatives to biofuel.

wind turbines

wind turbines

If that same land area is used for wind turbines, solar thermal or photovoltaic applications, much more energy can be harvested. The 60 gallons gasoline equivalent per acre from corn ethanol represents less than 2000 kilowatt-hours per acre per year. Dedicate that same land mass to wind turbines with “good” winds and you get 130,000 kilowatt-hours per acre per year. And the land beneath the wind farm is still available for crops or pasture.

Photovoltaic systems are even more productive.rooftop_PV Virtually anywhere in the US, 800,000 kilowatt-hours per acre per year is attainable with current technology, That is 400 times as efficient as corn ethanol. We don’t need cropland, we can do it on our roofs. We get to eat.

In summary, photosynthesis is a very poor choice when it comes to energy production because it is so inefficient and it competes with food crops for land and water. Solar energy production methods such as photovoltaics and wind with current technology can sustainably power our future, now.

Arkansas Health Care

Generally speaking the quality of health care in a nation follows from the wealth of the nation. The economy of the United States is the largest in the world. When you divide the economy by the number of people (per capita GDP) we still fare well, generally in the top five depending on who you measure and who’s doing the measuring.

If you have money we have about the best health care system in the world. But if you don’t have the money, not so much. Measures of health of the population are not so rosy for us.cost_longlife75 Something like forty or so countries out of about two hundred, some much poorer than we have lower infant mortality rates, longer life expectancies, and a better overall quality of life. Most of western Europe, Asian countries such as Japan and South Korea, even Cuba out rank us in these health care measures.

Within the United States, Arkansas fairs poorly in these measures with a relatively high infant mortality rate (14th among the 50 states) and shorter life expectancy (7th shortest). The Patient Protection and Affordable Care Act colloquially referred to as Obamacare should help advance Arkansas’ standing in the United States and our standing in the world.

The reality is that we are a poor state, ranking very near the bottom in median income. That translates to a larger than average fraction of the population without sufficient health care. To bring better health care to those without, Arkansas has chosen to expand our Medicaid rolls as part of Obamacare. The lion’s share of this will be born of federal dollars. One hundred per cent of the cost of Medicaid expansion will be covered by federal dollars for the first seven years, and ninety percent thereafter.

This will add close to a quarter of a million Arkansawyers to the rolls of the insured, and should help to lower our infant mortality rate and extend life expectancy. In the long run this will also help lower the cost of insurance for those already insured. How so you ask? Read on.

The cost of health insurance to an individual is dependent on what the insurer has to pay the medical community, doctors and hospitals. Both law and ethics require the medical community to treat both the insured and the uninsured. To recover the cost of taking care of the uninsured, doctors and hospitals charge the insured a rate that keeps them in business. Here is an important point: The more insured the fewer uninsured. The fewer uninsured, the lower will be the premiums for the insured.

An additional cost savings of better health care for the less fortunate is the fact that those with insurance tend to get better primary and preventive care. It is ever so much cheaper to provide an inexpensive diuretic to lower blood pressure than to treat a heart attack or stroke.

In the grand scheme of things it is cheaper for the haves to help out the have nots, unless you are willing to turn a blind eye on the sick, to literally block them from the emergency room door.

“…the moral test of government is how that government treats those who are in the dawn of life, the children; those who are in the twilight of life, the elderly; those who are in the shadows of life; the sick, the needy and the handicapped. ” Hubert H. Humphrey

5.4 kW grid-tied

Cost of PhotoVoltaic (PV) Systems

Because of the previous high cost of photovoltaic (PV) panels, their use has been limited to rather specialized and unique purposes. PV panels have and continue to be used to power satellites, and remote sensing facilities on earth where traditional energy sources such as electricity provided by power plants was unavailable.

In the 1970s those PV panels that were used to power satellites cost close to eighty dollars per watt. By the turn of the century the cost of panels was down to the vicinity 8 dollars a watt. And the price continues to drop.pvcost When I put in the panels to power my home in 2008 the cost was around five dollars a watt.

The current cost of PV panels is now approaching one dollar a watt for small home scale systems. This results in a system payback time of about ten years. Imagine, you pay one upfront cost for for a system, it pays itself back in about ten years, and you have free electricity for the rest of the life of the panels which is well over 25 years!

So lets talk about the nuts and bolts of a system. It consists of three components, the PV panels which produce direct current (DC) electricity, an inverter to converter the DC to Alternating Current (AC), the stuff that powers you home, and storage for when the sun isn’t shining.

If a home is already connected to the grid then storage isn’t an issue. A “grid-tie” can be used as the storage, eliminating the considerable cost of batteries. The net metering law in Arkansas allows producers to utilize a bi-directional meter. When the sun isn’t shining power is drawn from the grid, when the sun is shining the meter runs backwards, crediting the production. A system can be sized to produce as much energy as is consumed.

And it doesn’t matter how big the system is, it always pays off in ten years or less. A larger system will cost more, but produce more so the break even point is the same regardless of size.

The average home is Arkansas uses about 1000 kWhs per month and hence has an electric bill in the vicinity of 100 dollars a month. Here is an illustrative calculation for the cost of a system to totally cover the electric needs for that household. The panels for a PV system should cost about 10 grand. Add in about 2 grand for a system inverter, and another 3 grand for installation and you get a total cost of about 15,000 dollars. There is a 30 % federal tax credit, a credit not a deduction, which will then lower the cost of the system to about 10,500 dollars.

For this household the system will generate all the energy needed to offset the billed amount of electricity, saving the consumer, now a producer, 1200 dollars a year. The payback time is less than nine years. And the system will continue to produce at this rate for two or three times as long as has been paid for already.

Do you have access to the southern sky? Then your roof, or open space can be utilized to pay for your electricity, and the cost can be spread over the life of the system. In the future companies like Entergy will be mainly involved in distributing energy, rather than producing it. Production will be at home.

Power to the people.