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Opinions are fun. My friends tell me I am someone with lots of opinions and that's fine since I don't get mad at others when they disagree with me. In this same spirit I am interested in hearing yours views as long as you are able to share your views without boiling over. I look forward to hearing from you. I tend to write in the form of short essays most of the time, but contributions do not need to be in this same format or size. Some of the content here will date itself pretty quickly, other content may be virtually timeless, this is for the reader to judge.


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Doing the math on energy                                                                                     Print this essay

Posted at: Dec/21/2009 : Posted by: mel

Related Category: Environment,

So I have been doing some reading and math with respect to a "carbon footprint". If the goal is to reduce the amount of carbon being expelled into the atmosphere, then we need a real goal....say 50% reduction. Switching from 160HP gas burning cars to 75HP plug-in electric cars is not actually a savings. In the U.S. we produce the majority of our electricity from either coal or natural gas. Factoring in transmission loss these sources still produce approximately 90-95% the same carbon as gas powered cars, especially when you factor in transmission loss. Surprised, the process of converting coal or natural gas into electrical energy is also not perfect, and a great deal of the energy in the coal or natural gas goes up the stack or out a cooling system as waste heat. I am not going to explain all the science here, but fundamentally the Second Law of Thermodynamics requires it so this can’t be avoided. Then there is the all the heat loss from the charging and discharging of a battery. Battery technology is fundamentally very heat intensive and inefficient to recharge. For the novice readers, simply said, not all the energy goes to the drive wheels, if there is heat radiating from the vehicle, it took energy to make that happen. Try charging a battery and at the same time put your hand on the battery, the heat you feel is energy that will not go to the drive wheels.

I know, there has been a lot of consumer noise about hybrid and plug-in electric cars. From the consumer standpoint of cost per mile to operate these are potentially very efficient vehicles technologies. Reducing the cost per mile as gasoline goes up and up is a good thing, but this does not mean we are actually reducing the amount of carbon being pumped into the atmosphere.

I know, you are raising your hand from the back of the room and you want to talk about solar, also known as photovoltaic. Solar electric generation is really cool stuff, but it is also backwards math. I could be sarcastic and call it “smoke & mirrors”, but I will leave that to others. Yep, it’s true that the sun is a very substantial energy source and harnessing it is a great idea. The challenge is how we make a photovoltaic cell. Current material technologies and manufacturing methods make these cells very energy intensive to produce. Once you factor in the expected lifespan of these components we are actually not any further ahead in reducing our carbon footprint.

Now I will be an optimist and believe that in a few years we could produce the solar cells economically. To meet the current energy needs of Los Angeles would by many estimates require 2300 square kilometers of desert being paved with solar cells. Even if industry could approach that kind of volume, there is still the unintended impact. 2300 square kilometers of dark solar cells would by their reflectivity change local weather patterns in ways we cannot begin to predict, but it is entirely possible they could create their own localized low pressure area. Woops, large scale solar array produces permanent cloud cover reducing effectiveness, sounds like a headline. I am also imaging the environment impact on various species of desert birds, lizards, rodents and turtles.

Based on current knowledge the remaining options are hydroelectric, wind and nuclear.

Hydroelectric is good within limitations. There is only so much water and gravity to be taken advantage of. Much like a house of cards, you just can’t change something without finding out there is an impact elsewhere later on. In the first half of the 20th century we created a lot of hydroelectric dams. Time has taught us that the damming of many of these rivers has had a detrimental impact on fish populations and waterway ecosystems. We are only now starting to see the environmental impact these dams have had. In response to the impact on fish populations and ecosystems we are now significantly limiting new dams and in many cases removing selected hydroelectric plants.

Nuclear is the logically choice, but as long as we give such a large voice to such a small group this option should be considered dead. It is interesting to note that France gets 80% of its electricity from nuclear power and by my math has the excess capacity to power half their cars if they were converted to electric. It pains me to admit that France might be doing anything right or at least ahead of us.

I know, I sound like a pessimist and I prefer not to. The big point I am try to make is that we have to be careful what we are actually talking about. If the goal is to reduce our foreign oil dependence or automobile tail-pipe emissions, hybrid-electric, and plug-in electric cars are a good path to go down. But driving an electric car does not mean you are pumping less CO2 into the atmosphere, it only means you are getting your energy from another source.

Fundamentally, if the goal is to pump less CO2 into the earth’s atmosphere we need to be willing as individuals and as communities to live a less energy intensive lifestyle. Accomplishing this could be almost earth shaking in scope. We would need to become very dependent on public transportation virtually giving up our personal vehicles. Western economies would need to move away from replaceable goods. This would mean holding on to the same TV, toaster, and cell-phone for 10 years or more which would have a significant impacts consumers and manufacturing jobs.

After 120 years of unfettered consumption of natural resources we are now beginning to see the impact. Our challenge is how we change in response. Are we trying to reduce our oil dependency, or our carbon footprint? The way we ultimately respond could be as significant to mankind as the transition over 100 years ago from an agrarian society to an industrial and manufacturing based society.

Comments (2)                                                                                                                                                    [Add Comment]


 

Stop the madness. The so-called Utopian dream of a planet with 500 million people is genocidal--and evil for those who think genocide in a good cause is a good thing.

I'm with Freeman Dyson. The only known way to save the planet is to generate and make electricity cheaply available 24/7 to all of the populated planet.

For those who think CO2 is an evil global warming pollutant, the best way to reduce your carbon footprint is to stop breathing. Literally. CO2 is not a pollutant in any way shape or form. It's plant food and human waste. CO and NO2 are pollutants and thank God for the engineers who figured out how to almost eliminate them from automobiles. You probably can't even kill yourself by locking yourself in a garage with a modern car running. CO2 is not pollution, is not a greenhouse gas (greenhouses head by preventing convection). The only proven link between warming and CO2 is that CO2 levels increase in the captured substitute data (ice cores and tree rings) after a period of warming.

Posted at: Dec/25/2009 : Posted by: Frank Hood

 

Frank,

I don’t dispute the distinction between CO and CO2, but CO2 is one of the byproducts of burning hydrocarbons such as natural gas, oil products, and coal.

So the real challenge is this concern over “Global Warming” (GW). I strongly believe GW is real and a result of greenhouse gasses. I question whether GW is catastrophic to humanity. There is no doubt that GW will cause change, and we all know how much humanity hates change.

Now for some basics in case we have a reader not as well informed as Frank.

What is Global Warming?
Global Warming is the gradual increase in global temperature (warming) due to change in the composition of the earth’s atmosphere. As greenhouse gases accumulate in the atmosphere, more heat from the sun penetrates the earth’s surface, and less heat escapes – creating a ‘greenhouse’ effect. The source of these greenhouse gases can be both natural, man-made, and a secondary man-made effect. I will get back to these shortly.

What are greenhouse gases?
There are six key greenhouse gases: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydroflurocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6).

There is no doubt that nature produces many of these gases. CO2 and CH4 are common products from volcanic activity and decaying organic matter. The currently level of volcanic activity is relatively low, but even if it was high, it would be beyond our control. Since there is plenty we do have some control over, it is more worthy of time and discussion. We get CO2 from a variety of sources, burning hydrocarbons is a common source of contention. CO2 is also a byproduct of mammals breathing (that includes people). I for one don’t want to be the person who foolishly tells everyone else to stop breathing, but seriously; with an estimated global population of 6.7 billion and still growing this is arguably the largest source of CO2. One of the most natural ways to scrub CO2 and produce oxygen is via photosynthesis. In photosynthesis CO2 and water are converted into biomass and sugar, a waste product of this process is the production of oxygen (for humans this is our favorite gas). So a good solution would be more forest. Unfortunately as our population grows we have to cut down more and more forest to make space for humanities ever increasing numbers and humanities need for forest products.

What I am saying fundamentally is that population growth rather than the burning of fossil fuels is likely the single biggest contributor to GW via the production of greenhouse gasses and thereby to Global Warming…So why all the focus on fossil fuels? This is actually the easiest thing to answer. As a parent one of the life lessons I have come to respect is that certain battles are just not worth fighting because despite my best energies, I can’t win. The biggest factor in GW is humanity and it’s ever increasing numbers. I suspect that our planet can’t effectively cleanse itself of the activities of more than 3-4 billion people. As mentioned earlier we are at an estimated global population of 6.7 billion currently. There is no effective way to regulate world population, especially with over 150 different national governments who each have their own agenda. Attacking the effects of fossil fuel is merely dealing with a challenge we might actually be able to change.

So now I am back to Global Warming. I believe strongly that GW has happened numerous times in earth’s history for various natural reasons. I suspect that the majority of the previous warming cycles have had a significant and maybe detrimental impact on the dominate animal and plant life of that specific era.

There is no doubt that the United States with the help of legislation has reduced, or at least stabilized its production of greenhouse gasses since the 1970’s. But we are talking about a global issue, where change has only begun in a few selected countries. Los Angeles has cleaner air than 30 years ago, but what about China and India? These countries are growing rapidly and they are producing greenhouse gasses at an alarming rate that is circulated across the globe.

Global warming as a result of greenhouse gas accumulation is very real. It is the result of a substantial increase in world population, a substantial decrease in forests supporting photosynthesis, and the large scale use (last 120 years) of burning hydrocarbon fuels such as oil, natural gas, and coal. Any solution that is not enacted on a global scale will ultimately prove to be ineffective. Humanity has only been around for a few thousand years. In this time our increasing numbers and our activities have begun creating change that will have a significant impact on where we live, how we live.

Or…our world population has grown to a level where we expel large amounts of CO2. The quantity of CO2 exceeds the current acreage of forests ability to convert it back to oxygen. Worse yet we are hacking down forest all the time to make room for these ever increasing numbers of people. Frank, I think this means I just agreed with you in a very verbose way.

Posted at: Dec/28/2009 : Posted by: mel


Laurence J. Peter
There are two kinds of failures: those who thought and never did, and those who did and never thought.
 
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