Monthly Archives: July 2019

Renewable Energy Milestone

Renewable energy achieved a significant milestone in April, surpassing coal as the greater source of power for electric generation in the United States. This record may not persist as April is a windy month and because of mild weather less energy is needed for heating or cooling. Regardless, it is a milestone that portends the future.

Electric power from burning coal has been in decline for over a decade. Nuclear power is flat and renewable energy is ascendant. Of the renewable energy sources, wind is the leader followed by solar. Hydropower, geothermal and biomass are relatively static.

Technological advances and economies of scale are responsible for the lower cost and therefore greater penetration of renewables in the electric power production marketplace. Wind turbines are getting larger and taller which makes them more cost-effective in both production costs and efficiency as taller turbines reach windier levels of the atmosphere. As for solar arrays, the advances are mainly in cost reductions due to economies of scale rather than greater efficiency at capturing sunlight.

About seventeen percent of the energy mix is now renewable, and that is dominated by hydroelectric dam generation. In absolute terms, wind produces about seven percent and solar a little under two percent. These numbers are small but the two sources have the greatest potential for growth. Wind energy production has increased a phenomenal thirty-fold since 2000. When it comes to growth, solar is the champ having grown one hundred times faster than wind; that is, a three thousand-fold increase in installed capacity between the year 2000 and today.
One of the beauties of solar is its scalability. Practical installations range from small home systems providing most if not all of an individual homeowners electric power needs up to utility-scale monsters that cover hundreds of acres. Slightly larger than home size installations are those for schools and churches. Even larger installations include power for businesses such as Walmart Supercenters. The real growth, however, is in utility-scale solar arrays.

Entergy, the main supplier for electricity in Arkansas is now producing power from a giant installation near Stuttgart. This facility has 350,000 panels covering 475 acres. It produces enough energy for 13,000 homes. Using this scale of production suggests that every home in Arkansas could be powered from an area less than ten percent of Lafayette County, the smallest county in Arkansas.
Wait just a minute you say, what about when the sun goes down? Not to worry, at least for a couple of decades. Power grid managers won’t worry until intermittent sources reach somewhere between thirty and fifty percent of the total load. Right now wind and solar represent less than ten percent. Two factors are important, source management and grid size. Although wind and solar are intermittent, they are also predictable, and increasingly so.

Utility grid managers have become quite good at wind and sun forecasting. They know about how much wind and solar power will be available in the short term and can effectively plan for alternate sources during those times. The total size of the US power grid adds to the stability. Power can be shipped for one region to another with the flip of a switch – well, that and a more robust national grid of transmission and distribution lines.

Dr. Bob Allen, Ph.D., is Emeritus Professor of Chemistry at Arkansas Tech University.

Hybrid, Plug-in Hybrid, and Full Electric Cars

Vehicles powered by electricity come in several flavors; simple hybrids (HEV,) plug-in hybrids (PHEV,) and fully electric (EV.) Their biggest advantage is that vehicles powered somewhat or completely by electricity are more efficient. This means they are inherently less costly to operate.

Toyota has led the charge with the introduction of their hybrid Prius in 1997 in Japan and 2001 in the US and the rest of the world. It is basically a traditional Internal Combustion Engine (ICE) and drive train. It has a small battery and electric motor which provides supplemental power, increasing the efficiency of the vehicle, even though the battery is charged mainly by the ICE. Scores of cars now use this hybrid technology and even a few pick-ups.

A very important component to all these electric vehicles is regenerative braking. When the car decelerates it causes the alternator in the vehicle to become a charging device for the battery, in the process slowing the vehicle without using the brakes.

Intermediate between simple hybrids and fully electric are plug-in hybrids. They are different in that they are true electric vehicles with an ICE to extend the range. The drive train in these vehicles are powered by the electric motor, the ICE is just used as a generator. The PHEVs have a battery which gives the vehicle a range of about 40 to 50 miles, generally enough for the majority of commuters. The vehicle can then be plugged in at home to recharge the battery for the next day’s commute. For longer trips, the ICE charges the battery on the fly.

The ability to charge a battery-powered car from the grid, that is by plugging into a wall outlet creates considerable savings as the energy to power a vehicle by electricity costs one third to one quarter as much as the cost of gasoline. Another bonus is cleaner air. Electric power is inherently cleaner than ICE power because much of the energy used to produce the electricity is from clean sustainable sources such as wind, solar and hydropower.

The real future of surface transportation is all-electric cars. These vehicles take advantage of regenerative braking and other computer controlled mechanisms. The EPA rates EVs by comparing the electric energy used to the amount of gasoline an equivalent ICE car would use. It comes out to something like 130 miles per gallon equivalent or better. Although electric cars initial costs are higher, over the lifetime costs are frequently lower than ICE vehicles due to lower fuel and maintenance costs.

By far and away the best known electric vehicle is the Tesla, built by visionary Elon Musk. Depending on the model, Teslas have a range of between 250 to over 300 miles on a charge. More importantly for Tesla however is the fact that a fast charging network has been built out across the US such that travel, at least on interstate highways, not a problem. The Tesla charge stations are located so that a 200 to 300 mile drive get one to the next charger. Charge times to fill the battery are on the order of an hour or less.

Dr. Bob Allen, Ph.D., is Emeritus Professor of Chemistry at Arkansas Tech University.

The Celebration Gap

Early in the cold war, there was a missile gap. In the late 1950s, America was threatened by the perception that the Soviet Union possessed superiority in the size and number of nuclear-tipped intercontinental ballistic missiles (ICBMs). Turns out the fear was unjustified, as President Eisenhower’s science advisory committee greatly overestimated the Soviet arsenal.

What threatens us now is a celebration gap. Actually, it’s a get away from work to relax gap. The Fourth of July is here. Most get off work to be with family and friends so we can celebrate our independence from the rule of King George. The problem is, when it comes to celebrations we’re a bunch of pikers. We have ten federal holidays, which are usually matched by states but we have no national holidays where all workers have an expectancy of time off – paid or otherwise.

In most of the world, the civilized world with the sole exception of the United States, laws afford workers a guaranteed minimum number of paid National holidays. Leading the world is arch enemy Iran with twenty-seven paid holidays. Most of Europe guarantees somewhere between ten and twenty days.

But it gets worse (or better depending on your perspective), not only does much of the world guarantee paid holidays, they also mandate vacation time. This is most commonly two to three weeks on top of the holidays. France is instructive, where all full time employees are guaranteed five weeks of vacation in addition to twelve national holidays. Oh, and they have thirty-five hour work weeks. Remember this is all full time employees, not just government employees but butchers, bakers and candlestick makers.

Should we Make America Vacat(ion) Again? Is there an advantage to taking time off or does it distract from productivity? There is significant evidence that worker productivity is better when interspersed with paid time off. One study showed that employees and were in a better mood and more effective in their jobs for over a month after a paid vacation. Another study showed that vacations increased net productivity and lowered stress.

Americans don’t get it. Almost forty percent don’t take a single vacation day in a years time. Even when vacationing, sixty percent take work with them. One of the longest-running collective studies of health, the Framingham Heart Study began in 1948 showed a positive correlation between vacation time and well being and longevity.

When compared to other nationalities such as Europeans, we work longer hours, spend less time with our friends and family, only to live shorter less fulfilling lives. Somewhere we seem to have lost our way.

Dr. Bob Allen, Ph.D., is Emeritus Professor of Chemistry at Arkansas Tech University.

Water Management

Exoplanets, or extrasolar planets, are simply planets that circle a star other than our own. First detected in the late 1980s, there are now thousands of known exoplanets. Although there is no current interest as a place to flee the ravages of our planet, the exoplanets are none the less of scientific interest.

The biggest problem as an escape route is the fact of distance, the nearest is over four light-years away. A light year is the distance light travels in one year or about six trillion miles. Despite being quite distant, the exoplanets are of interest as possible sources of other life in the universe. To accommodate life as we know it requires one universal – liquid water.

Water has unique chemical properties as a solvent that no other substance really can compare. Chemistry and thermodynamics, anywhere in the universe, combine in a way that makes life inconceivable without it.

With an abundance of water on this planet, one might think it is not an issue but increasingly it is. Specifically the availability of manageable water. Global warming and the climate change that follows therefrom is making the management of water difficult.

Sea levels are rising and rising faster than previously predicted. A recent study in the Proceedings of the National Academy of Sciences has suggested that the sea level rise may be as much as six feet by the end of the century, more than twice the prediction of just a few years ago. And lest you think the end of the century is a long way off, it is within the lifetime of someone who could be reading this column today.

Whole cities will either have to be abandoned or pay incredible costs for infrastructure to hold the seas back. Forty percent of the world’s population is coastal, that is live within fifty miles of a seacoast.

Meanwhile farther inland, managing water is being made more difficult. Billions of people around the world depend on meltwater from the mountain snowpack. The regions which include the western United States, Alpine Europe, Central Asia and downstream of the Himalayas and Tibetan Plateau contain nearly half the human population of the planet. Global warming is threatening the timely delivery of freshwater. More cold season runoff can overwhelm reservoir storage of water, making less water available later in the growing season.

We’ve recently had a lesson on water management with the historic flooding of the Arkansas River valley. Serious to catastrophic failure of levees is responsible for disaster declarations in a sixth of Arkansas Counties. Levees and other flood control structures will have to be not just replaced but radically upgraded to accommodate changing rainfall patterns.

At every turn, climatic instabilities force greater expenditures on infrastructure. This is the cost of climate inaction. The sooner we act to reduce the rate of global warming, the less we have to spend on mitigation. We have economically practical technologies to stop driving global warming. Wind and solar electric energy coupled with battery storage can power the world. We must wholeheartedly invest in the future, now. Or do we abandon our children to our unaddressed climate disasters?

Dr. Bob Allen, Ph.D., is Emeritus Professor of Chemistry at Arkansas Tech University.