2012 04 20

The most annoying thing about TV and radio news is any explanation of any position must be made within 15 seconds or it won't be made. Even as I pick up the pen to explain what I'm about to explain I'm worried that most readers won't have the patience to read it - and I'm going to keep it as brief as possible.

I'm really annoyed over the Green Energy chatter. I think most people see energy in catagories:

Bad for the environment:

Not Bad for the environment (i.e., green):

I strongly reject the notion that the energy under "bad" is really bad - and I reject the claim that the items categorized as Green are any better.

For one thing, all the stuff discussed as green are really just solar or stored solar energy. Some are really obvious while others are less clear if the reader doesn't understand the definition of energy.

Solar energy is, obviously, solar; but even then, we tend to want to convert it as quickly as possible into a nice portable form such as electricity (usually potentially stored in a battery for later use.)

Any energy that comes from a plant is stored solar energy. After all, why are leaves green? The process of photosynthesis occurs when sunlight shines on a leaf. The plant uses the energy to rip the carbons out of CO2 molecules (leaving the oxygen in the air for mammals to breathe). The plant takes the carbon atoms and some water molecules and manufactures sugars of various kinds. The products are used to fashion plant material (the plant grows). The sugar molecules are stored solar energy. Later, if you burn the plant (for example), the heat that is released is that same solar energy. If a scientist converts the plant material into a liquid - say, ethanol, and later burns it, that heat is stored solar energy. Does that make sense?

What if we used the energy stored in pork fat? Say, we build a motor that burns pork fat and we use it to turn an electric generator. Where did the energy in the pork fat come from? Well, if the hog was raised on vegetables, see the above discussion on photosynthesis. The digestion converts some of the sugar in the plant into fat. If the hog was fed nothing but chickens - well, hopefully you can follow the energy trail.

Let's talk a little bit about hydro-electric energy - by which, I mean the use of river water to turn turbines to generate electricity. Where did the energy that is being taken from the river come from? I claim it is another form of solar energy. I'm not going to give a complete physics lesson here; but let's remind ourselves of the difference between potential and kinetic energies. The kind of energy we love is kinetic energy. That's the energy we see in action. It's cooking our food. It's making that lightbulb glow. It's making that radio make sound.

I can make a simple energy storage device to illustrate potential (stored) and kinetic (working) energy. Consider the following scene. There are two cars and a hill. There is no energy in either car.

If I push one of the cars up the hill, the car becomes capable of doing work. I did work by pushing the car up the hill; but the energy I used to push the car is in fact stored in the car.

It's a rudimentary battery that is storing energy. Now, that energy can be used up by simply letting the car roll back down the hill; but that's not very interesting. If I tie a string between that car and the other car (which still has a zero energy state), then when I let the car roll down the hill it can do something useful in the process. In this case, it is used to pull the other car up the hill.

Now consider another simple machine. A weight is tied by a string to an empty beaker. The string is slung over a pulley. Now, I rig up a kettle of water to be heated by some burning wood that was formed with solar energy. The water gains energy by heating up and much of it is pushed up a tube (ultimately caused by the energy from the burning wood).

As the water vapor increases in altitude it cools - and the energy is stored in the water molecules as potential energy. They are distilled and transferred into the beaker. This device is another energy battery that can be used to lift the weight. Does this make sense to you? that the weight of water can be transferred into a potential energy system simply by being evaporated and distilled?

Do you realize the same energy storage system happens when water vapor comes up from the oceans and distills (rains) over land and runs down rivers - and turns turbine generators in river dams?

I'm not in favor of wasting that hydro-electric energy; but it's just stored solar energy.

Now, lets consider coal. Coal is ancient plant matter, right? So, the energy that is in coal is energy that came from the sun a long time ago and is stored in the coal. If I burn a piece of coal, the energy that is released is ancient solar energy. Burning crude oil is also the process of releasing ancient solar energy.

In fact, the only energy sources generally thought of as useful that are not solar are nuclear and geothermal (geysers). Nuclear energy exists in abundance on this planet. I'm a little suspicious of siphoning off the energy of the rotating planet because it requires slowing down the rotation of the earth and transferring the energy into some other form of energy.

If solar energy is green, then fossile fuels are green.

By the way, everybody is so terrified about CO2 getting in the atmosphere. Have you thought about where those carbons were before they were in oil? They were in (probably) animal fat, and before that in a plant and before that in the atmosphere!