Monthly Archives: September 2013

large solar array

Solar Steel

People often think that solar photovoltaic panels are OK to put on a roof to cut ones electric bill a little but really doesn’t go far to fill the needs of the nation when it comes to electricity. Or that it’s OK for light weight usages like lighting in parking lots but can’t provide for heavy industries like steel mills. I would like to disabuse those folks of the idea that solar can’t keep us going.

First some fundamentals. Electrical energy is measured in Watt-hours (Wh) or multiples there of. If your monthly electric bill is about a hundred dollars, close to the Arkansas average, you are using a MegaWatt-hour (MWh), which is a million times a Watt-hour. This amount of electricity is available year around from a space about twenty seven feet on a side. It easily fits on a south facing roof. A system like this will not just lower your bill but eliminate it.

Let’s talk about power for heavy industry, and it doesn’t get much heavier than steel mills. Nucor Corporation operates twenty-three steel mills

electric arc furnace

electric arc furnace

across the United States producing twenty-two million tons of steel annually employing electric arc furnaces. If we can figure out how to do this with solar panels we can do anything.

It takes about one and a half Mwh electric to produce a ton of steel. On average each plant produces a million tons of steel a year, so we need one and a half TeraWatt-hours;

steel

steel

a TeraWatt is a million times a MegaWatt. How much land do we need per plant? It works out to one thousand five hundred acres. This is equal to the land use of less than four average farms in Arkansas. That’s it. The land occupied by four farms in Arkansas will provide enough sunlight to power a steel mill. Cool, huh?

When you look at total electric use in the United States over a year the numbers get really big. The national annual electric use is four PetaWatt-hours; a PetaWatt is a billion times a MegaWatt. So how much land would it take to generate all the electric power we use in the United States? A surprisingly small nine thousand square miles. This is an area smaller than Rhode Island.

The numbers I cite are good for the amount of sunlight in Arkansas using flat plate collectors. If the national power grid originated in Nevada using tracking panels, the area needed is less than five thousand square miles. There are counties in Nevada much larger than that. There is no question that sunlight alone can provide all the electric power we need in this country.

The obvious fly in the ointment is the need for storage when the sun doesn’t shine, or transmission to where the sun doesn’t shine, but both those limitations are under study and are an achievable goal in the near future. And that’s just solar Photovoltaics as an energy source. That amount of energy is available from wind turbines and the potential for geothermal is greater still.

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.

Professor Mark Post holds the world's first lab-grown beef burger during a

Petri Patties – Lab Grown Meat

Even though we have yet to recover from the current recession, we still lead the world in economic might and that is reflected in our high rates of consumption of everything from crude oil to meat. Both of these commodities contribute to our exaggerated contribution to global warming.

As other countries expand their economies, that is become more wealthy, they tend to eat more meat. China in 1961 consumed four kilograms per person. By 2001 that jumped to fifty-four kilograms. Currently half of all pork produced in the world is consumed in China. By comparison the US eats over one hundred twenty kilos of meat per person per year. By the year 2050 global meat consumption is estimated to double, from the current 230 to 465 million tons.

The connection between meat consumption and wealth is easy to see. Protein from meat is expensive. The cheaper alternative comes from diet that balances beans and grains to provide complete protein – nutritious but bland. So what’s the harm if you can afford meat? Two factors; personal health effects such as heart disease correlate with high meat diets, and meat production contributes to global warming.

Enter the lab burger,stage left – PETA has a bounty out for the first practical lab grown meat. A study done a couple of years ago suggests that if meat could be “grown” in the lab, about 50 per cent less energy would be used, virtually no land would be needed, and ninety per cent less green house gases would be emitted compared to traditional agricultural methods. These environmental improvements result from considerable decreases in methane release from ruminants and decreased deforestation not needed for feed; corn and soybeans, and fodder; grass from pastures.

We now have a Petri patty, not practical by any measure but at least the proof of concept has been achieved. Last month a celebrity chef in London, England prepared the world’s first and only hamburger made from meat grown in cell culture in a laboratory in the Netherlands. The idea of lab meat is not new. As early as pre-world war II, Winston Churchill wrote about the possibility. He was concerned that a war which resulted in a blockade of the UK could threaten the population with starvation.

The process is simple in principle but extremely difficult in practice. The simple explanation: take a muscle cell from a cow, stimulate the cell to divide in a nutrient broth, and voilà! The lab burger. In practice the process took several years and over four million dollars. Tissue harvested from a carcass is first treated with an enzyme to remove connective tissue and release the muscle cells. The cells are cultured in fetal bovine serum, a fluid taken from slaughtered calves. Alternative cell culture media exist but performed poorly. Because the cells lack any vasculature the cells can only be grown in thin films. Also methods had to be developed to “exercise” the developing muscle tissue.

One final problem is physical, the cells are colorless and without fat so the lab meat was colored with beetroot juice and cooked in butter and oil. For cultured meat to become a real alternative it has to be a whole lot cheaper, redder and fattier.

Colorado River

Extended Drought in Southwestern US

One of the projections of climate change due to global warming is alterations in rainfall patterns. Warmer air will hold more moisture so one might think that global warming will cause more rainfall and generally that is true overall, but another feature of global warming is a redistribution of rainfall, more falling on the coasts and less in the continental interior.

Additionally, the rainfall patterns are predicted to change to more intense storms where larger amounts of rain occur over shorter time spans. Heavy rains mean more runoff, hence less water available for the myriad of uses we depend on – energy production, agriculture, industry, recreation and most importantly drinking water.

>The Colorado River and its tributaries drain a basin of a quarter million square miles. Forty million people in six western states [Colorado, New Mexico, Utah, Wyoming, Nevada, Arizona] are directly in the line of fire of climate change. For millions of years the Colorado has flowed from the upper reaches of the Rockies to a large delta at its confluence with the Gulf of California.

Not so much any more. A combination of drought and pressure on the river from agriculture and burgeoning cities has reduced the flow to the point that in recent years the Colorado no longer reaches the sea. Virtually every drop is removed for irrigation in the Imperial Valley of California, to cool coal-fired power plants around the Four Corners area, and to water golf courses in Phoenix.

Global warming and the attendant climate change is predicted to decrease precipitation by twenty percent in the watershed over the next forty years. This will greatly exacerbate the issue of the availability of water in the southwest. The water level of Lake Powell,

Lake Powell on Colorado River

Lake Powell on Colorado River

formed by the construction of the Hoover Dam is at an all time low, some 120 feet below its high of a decade ago. Images show what appears to be a “bathtub ring” on sandstone bluffs along the lakeside.

Another distressed southwestern watershed is the almost two thousand mile long Rio Grande which demarks much of the border between the US and Mexico. The two hundred thousand square mile basin has been stressed by a decade long drought, and it appears to be getting worse due to global warming. Two significant reservoirs, Elephant Butte and Caballo are at less than ten per cent capacity.

Elephant butte Reservoir

Elephant butte Reservoir

Like the Colorado, the Rio Grande doesn’t make it to the sea. What little flow exists is removed, mainly for irrigation. The flow essentially ends by the time it reaches Presidio, TX.  Other significant water courses in China, India and Australia are distressed to the point of no exit flows. The problems are real and worsening with increasing population demand and climate change.

Global warming is real, we are causing it and we need to address how to stop,even reversed it, in addition to the immediate need for adaptation to the new climate we are forcing.

reactor schematic

The Future of Nuclear Power?

There are discussions among members of the environmental community about nuclear power. Some have suggested that nuclear power can be part of the solution to curbing the release of greenhouse gases. Others disagree.
Dr Amory Lovins, noted physicist and sustainable energy guru, notes that “Each dollar spent on a new reactor buys about 2-10 times less carbon savings, 20-40 times slower, than spending that dollar on the cheaper, faster, safer solutions that make nuclear power unnecessary and uneconomic”. Then there is this:

In March 2011 a magnitude 8.9 earthquake and subsequent tsunami has initiated a crisis in northern Japan. Damage to several nuclear reactors has caused the leakage of three hundred tonnes of radionuclide containing water into the ground and nearby sea.

Four of the six reactors at the Fukushima Nuclear Power Plant were irreparably damaged.  Although the reactor cores may not have suffered any catastrophic failure of the containment vessels, partial meltdowns have occurred. Partial meltdowns occur when the fuel in the core gets so hot that the metallic cladding of the fuel rods melt. This means that the reactors will never be used again and in fact constitute a huge expense for cleanup.

Radiation due to fissile isotopes has been detected at levels some 400 times normal in the soil about 25 miles from the plant and traces of radiation have been detected in air as far away as Seattle, Washington. An ocean plume of radioactive water will reach the US in 2014.

ocean plume

Ocean Plume

The relative risk is unknown but simply calls attention to the magnitude of the damage which has occurred at the reactors in northern japan.

Much of the radiation must be coming from the on-site waste storage. The issue of nuclear waste continues to plague the nuclear industry in one form or another. We all want the power, but nobody wants the waste.

The problems at the Fukushima plant are due mainly due to the loss of power on site. The diesel generators which should have provided backup power to the site to maintain reactor coolant water failed because of the tsunami. Because of lack of coolant water, the fuel rods overheated, causing the metal cladding to melt, then react with steam in the reactor to produce Hydrogen. It was this Hydrogen which caused explosions in two or more of the reactor buildings. These explosions damaged the spent fuel pools which allowed water to leak out, thus precipitating radiation leaks.

The fuel rods in the spent fuel pools constitute high level nuclear waste. Unlike the fuel rods in the cores of the reactors, those in the spent fuel pool are not within any containment barrier. Rather they sit at the bottom of a swimming pool like structure. When coolant water is lost from these pools the rods overheat, melt and release radioactivity.

Every reactor in the United States stores its high level radioactive wastes in this relatively insecure fashion. The wastes are stored in the pools for five to ten years until cool enough to be moved to other storage locations. Severe weather events such as tornadoes, flooding, hurricanes, or even terrorists could damage the integrity of the fuel pools, unlike the much more secure reactor cores.

If nuclear power is to have a renaissance, there must be greater attention paid to the issue of on site waste storage. Of course more secure handling of wastes will only add to the cost and it is ultimately cost factors which will determine the fate of nuclear power here in the United States.