Monthly Archives: October 2019

Energy Storage Efficiency

There are those who constantly dismiss wind and especially solar as impractical energy sources because it is not available all the time, hence standby power must be available – fair enough. Right now Unit One of Arkansas Nuclear One is offline for refueling.

So is anybody sitting in the dark for a month or two? Of course not. Must there be another nuclear reactor standing idle waiting for Unit One to go down for refueling? Again the answer is no. There is sufficient excess capacity in our electrical grid to make up the difference in electrical energy needs during the outage. The same is true today for our intermittent energy sources, wind and solar. It is estimated that no additional backup will be needed until we reach about thirty percent contribution of these renewable sources to our total electric production.

Right now wind turbines to our west and the solar panels at my home use the grid as storage, just like Unit One. When the wind isn’t blowing, the sun isn’t shining, or Unit one is offline to refuel, the other power sources in the grid make up the shortfall. Electrical energy transmission and storage are hot research topics in science and technology. Numerous ways exist already for grid-scale energy storage, the ongoing research is to find ways to store energy efficiently and affordably.

One option being explored by as Swiss company is a cuckoo clock writ large. Excess energy is used to raise concrete blocks up, just like the weights on a clock. To recover the stored energy simply allow the weight to go down, turning a generator as they come down. This type of energy storage is not very efficient, maybe sixty to seventy percent, but is inexpensive.

At the other end of the spectrum is a high-cost, high-efficiency strategy such as a rechargeable Lithium-ion battery. The efficiency here is about ninety percent. Although expensive, Lithium-ion batteries are quite lightweight so they have value to power portable devices, from hearing aids to electric cars.

One energy storage medium that most don’t recognize as such is Hydrogen. Hydrogen gas is very energy-dense, meaning a small amount of it will store a lot of energy. Hydrogen can be generated by electrolysis of water. The hydrogen can be stored until energy is needed, then the hydrogen can be burned to make steam to turn a turbine to generate electricity. But, burning anything to produce heat to turn a turbine is a quite inefficient process. Because of the laws of thermodynamics, you can only get back about a third of the energy put in.

Better than burning to make heat is another technology known as a fuel cell. Fuel cells convert Hydrogen back to water without as much waste heat. Hydrogen generation via electrolysis, then conversion back to electricity has a “round-trip” efficiency of about fifty percent.

The science and technology of grid-scale electrical energy storage will mature as we expand our reliance on wind and solar, ultimately eliminating the use of fossil fuels.

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

“Impossible” Food

Within the last few months advertising for “impossible food” has ramped up. Actually, Impossible Foods Inc. is a California company – where else – which is focusing on producing veggie burgers. Some companies have been around for years and others are now jumping into the market. Why?

Beef, along with other animal sources of meat constitute an excellent source of protein. Americans eat an average of about 250 pounds of animal protein, including fish and shellfish, annually. There are alternative sources of protein such as a diet that balances beans and grains, but strict vegetarian diets must have an additional source for Vitamin B12.

The easy and tasty nutrition of meat, especially beef, does come at a cost. Much of the arable land in the United States is dedicated to the production of feed for the animals we eat and animals are not very efficient in turning the calories they eat into the protein we desire.

Energy inputs to raise animals come in the form of the energy needed to produce crops for animal food, mainly for fuel and fertilizer. Beef, the one we eat the most of is at the head of the inefficiency lists. It takes 33 units of energy to produce one unit of beef. Pork is better at 11 units in per unit out. Chicken is even better at 5 in to 1 out.

So where is all that wasted energy going? It is complex but boils down to two main factors, digestive inefficiency and basal metabolism, essentially heat production. The consequences of this waste is significant. As mentioned, land use is dominated production of animal feed. The CO2 released from fossil fuel use contributes to global warming. Much of the Methane released which also contributes to global warming comes from agriculture.

Animal wastes, feces and urine, can be a significant issue as we have recently seen in the fight over the hog factory operation in Mt Judea. A combination of public and private money, amounting to millions of dollars will be spent to close the farm and prevent further damage to the Buffalo National River.

Phosphorous and Nitrogen applied to crops as fertilizer runs off and ends up in the ocean. There is currently a several thousand square mile area at the mouth of the Mississippi River that is called a dead zone. Nutrient overload here ironically prevents virtually anything from growing.

All the issues of land use, global warming, and nutrient pollution would greatly benefit from the adoption of a vegetarian diet. Land use could shrink by a factor of ten if we ate beans and grains rather than feeding them to livestock. Similarly, agriculturally driven production of green house gasses and nutrient pollution would be reduced.

Now back to the impossible foods. Vegetable-based burgers and such have been around for sale at the grocer’s for years and in few restaurants but seldom before in fast food chains. Now you can get an impossible whopper. The faux meat patty is made from soy protein with numerous amendments to simulate a real burger.

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

Global Warming as a Threat Multiplier

The single most important, essentially all-encompassing function of government is to keep us safe. This too often is thought of only in terms of physical violence; you know the line, defend against all enemies, foreign and domestic… But other factors threaten our well-being. Climate change, floods, droughts, and intensified storms affect us all. Additionally, these factors can serve to magnify the risks of many others, especially military and political.

The term “threat multiplier” is used not just by what some call climate alarmists but also the Pentagon. The US military gets it.

Refugee crises have driven some countries into the hands of autocratic leaders who talk tough but at the expense of democracy. Refugees from the Middle East wars strains the patience if not the resources of Europe. The wars are ultimately political but the politics can be driven by environmental factors.

The bloody and seemingly endless civil war in Syria was preceded by a drought that drove farmers from the fields and herders from the pastures. Without work, the former herders and farmers were easily conscripted into the arms of warlords who paid them to kill not till.

The civil war in Yemen was begun over political power. Climate change is multiplying the suffering of the people. In the past, villages would store enough food to last for three or four months in times of emergency. In recent years less rainfall, resulting in reduced harvests, means little if any food is stored for periods of crisis. There is arguably no greater crisis than war.

Now, this civil war threatens to spiral into a broader war between Saudi Arabia and Iran, or even engulf the whole region in conflict and misery.

The presidential election of 2016 was dominated by Trump’s call to “build the wall.” Although immigration was at the time at a fifty-year low, increasing numbers of refugees from the Northern Triangle region of Central America now threaten our stability.

Refugees from Guatemala, Honduras, and El Salvador are fleeing violence born of lawlessness. Again these conditions are made worse by climate change. The region is getting hotter and paradoxically, both floods and droughts strain agriculture. What rainfall occurs happens in fewer, heavier events. Flooding followed by periods of drought. To stay alive in hard times, many, especially young males, turn to violence as their only recourse.

Not acting to reduce the rate of global warming will exacerbate problems across the board. Climate change itself and all the troubles that the change serves to multiply the ravages of war, famine, and refugee crises.

The good news is that there are solutions. Sustainable energy supplies that don’t add carbon to the atmosphere are cost-effective replacements for fossil fuels. Utilities and some cities here in Arkansas are adding large scale solar arrays to their energy mix. The cities of Clarkville and Fayetteville have installed arrays with the intention of powering all city functions. Hot Springs has recently signed contracts to do the same. Even the Dover School System is examining a solar power option.

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