the Air Vent

Because the world needs another opinion

Energy and politics

Posted by Jeff Id on August 10, 2008

Ok I just wrote an entire article about energy. I started small and before I knew it I had several pages. Unfortunately what I first posted contained some ugly errors and I had to repost. I screwed up and my first real post got deleted …..completely. I think I can recreate my 4 hours of work a bit faster this time but I am frustrated.

Right now there is a big discussion about drilling for oil vs alternative energy or both. Alternative “green” energy includes biofuel, solar, nuclear, wind, wave, geothermal, and others I’m sure. The now not green energy includes any form of wood, oil, natural gas, coal or anything with evil carbon in it. Why isn’t wood a good biofuel? I can’t figure that out.

As often is the case in what appears to be complicated, a small amount of math can give some interesting results.  Let’s do some energy calculations for fun.

To begin with we in the US used 28.352 trillion BTU’s of power for our cars in 2005. Our power plants produced 39.928 trillion BTU’s in 05 according to the department of energy here.

In watts hours (a different unit than btu which means the same thing like feet and meters) we produced 11.7 trillion watt hours electrically and our cars used 8.3 trillion watt hours. The net result in 2007 is about 390million gallons of gas burned with each gallon containing 121million Joules of energy. A Joule is an energy measure similar to BTU.  The vast majority of the gas is burned in cars.

If you use 1 joule per second you are using a power of 1 watt.

So our cars use 390 million gallons per day x 121 million joules or 4.71 x 10^16 joules/day or 546 billion joules per second which is 546 billion watts —– Wow!

For interest the total gallons per second is 390/3600sec/hr/24 or 4513 gallons/second.

The eco guys hate natural gas, coal, nuclear, oil or anything we can easily use and want us to use biofuel, or various forms of solar or geothermal. What is needed in today’s discourse is a rational discussion about these subjects.

Hydrogen power cars

I love reading the liberal posts about how we will use water to power cars. I would say less than 5 percent of the posts on treehugger.com have any clue what they are saying. But they will say it as loud as they can. I couldn’t believe that there were several posts from people getting angry that anyone would use water to miraculously power a car because we would run out of water next. Morons…. If this is your concern then you have failed the IQ test for this site and should look elsewhere. We talk about numbers here.

Well we can’t fix everything so let’s talk about energy.

There is no such thing as an energy shortage. Einstein provided us with a nice equation which we all recognize E=mc^2. This means that mass is basically energy tied up as particles. Not a little bit of energy either actually it is really. ….. really big energy. The energy in the Nagasaki atomic bomb was equivalent to only 1 gram of matter being converted directly to energy. This is equivalent to a small paperclip releasing 100% of its energy. The important thing to remember is that any mass has the same energy 1 gram of wood, water, lead, chicken, anything is exactly equal. The only problem is we aren’t wise enough to release it yet, it’s a good thing too because I own a lot of paperclips and I don’t want to see one go off.

What we have instead, is a convenient energy shortage created by policies with dubious intentions. Convenient energy includes coal, natural gas, nuclear, wood and a number of other sources which work quite well using our current technologies. Today though I want to calculate the plausibility of alternative “green energies.”

To get rid of or remove fossil fuels in our cars we need an alternative. Hydrogen is a good alternative because it burns super clean, and recombines with oxygen primarily into H2O.

For a hydrogen car to work we need to get hydrogen. Since we cannot easily mine hydrogen directly, this will be captured from electrolysis of water. When direct electric current is applied to water (H2O) Hydrogen is released from one electrode and oxygen from the other.

Splitting a water molecule requires energy. The amount of energy absorbed by the water when split is exactly … exactly equal to the amount of energy released when the hydrogen burns and turns back into water. You cannot save energy by splitting (through ridiculously complex or magical process) and recombining the same elements.

Fortunately MIT recently discovered an improved method for splitting water HERE. This is not a minor breakthrough and if it is completed, it will change wind, solar and wave power possibilities for years to come. The true efficiency of the process hasn’t been determined but it is supposedly much much better than now. For my calculations below I will assume an excellent 30% loss in converting electrical energy to hydrogen energy.

So with our new technologies we can do some basic calculations of how much solar would it take to make clean solar power for cars.

Arizona is in the process of making a state of the art solar power plant which uses heat to boil water or something and make energy. The plant is called Solana and you can visit it here.

The plant is expected to produce a peak of 280 megawatts (million watts) of power on 1900 acres or 7.7 sq kilometers. The plant is a big step forward in solar power and will produce no greenhouse gas. To split water for hydrogen and oxygen to replace all of the gasoline we use will require 546 billion watts of continuous power with perfect efficiency (see above). If we assume an excellent 30% loss we can take 546*1.3 = 710 billion watts of power required to make the hydrogen for our cars.

At night the sky is dark so the 280 megawatts of solar drops to zero and in the evening the light is dim so we will say the system produces an average of 280*1/2 (for night)*.8 (for evening) or 112 megawatts average for 24 hours.

The number of advanced solar plants required would be 710 billion watts required/112 million watts per Arizona solar plant or 6339 plants to power all of the US cars on solar power. At 7.7kilometers per plant times 6339 we get 48,812 square kilometers of power plant in Arizona.

Arizona has 294000 sq kilometers so if we covered 48812/294000 or 16 percent of Arizona with power plants we could power all of the US cars on solar. I’m not a big fan of Arizona anyway (just kidding).

The cost per power plant of this type is estimated at 1 billion dollars so the total cost to build the plants is 6.3 trillion dollars. Ok, that’s a big number. But we are sending 700 billion per year overseas for oil right now.

Let’s see, the estimated cost per kilowatt hour is $0.20 that translates into 3.6 million Joules for $0.20. For one gallon with 121 million Joules the cost translates to 121/3.6*.2 or $6.72 per gallon equivalent energy. Let’s not forget our very hypothetical conversion efficiency for creation of hydrogen of 30 percent loss so we have nearly achieved the technical ability to replace gasoline of $8.74 for the gasoline energy equivalent amount of hydrogen with excellent conversion.

So after my long winded analysis which favored the solar plant at every turn we have determined that this plant can produce the hydrogen equivalent of one gallon of gas for 8.74 Wow again.

I tell you what I cannot see an investment of 6.3 trillion when the hopeful payoff is 8.74/gallon gas replacement with zero emissions. Of course they aren’t trying to make hydrogen, this plant will just produce electricity for homes but energy is energy and cost is cost.  Arizona, take my advice and burn some oil, build a nuke, do anything else but this plant is an obvious boondoggle. What a colossal mistake, I had no idea until I did the calculations.  

Still it’s a cool project but it’s not even close to ready for prime time.

A short look at biofuels

Unlike solar power, I can tell you that biofuels are a scam before I do the calculations. Any reasonable engineer with a pencil and a napkin will tell you the same but let’s do it anyway. It wouldn’t even be an issue without the huge subsidies (cash handouts) from the government.

For corn and soy a generous amount of biofuel per acre is 150 gallons of ethanol (you can find many sources on the internet). It takes considerable power to make corn and soy beans into gas. For some time there was a debate as to whether it took more fuel to make the ethanol than it produced. Today some report a reasonable number of 1.35 gallons of ethanol to 1 gallon of processing fuel. So we net .35 gallons/gallon actual. For 150 gallons we get 38.8 gallons of usable fuel per acre.

If we assume 1 gallon of bio-fuel is equal to 1 gallon of gas (it’s not) but it is close. We need 390million gallons/day or 142.35 billion gallons per year. This requires 142.35billion/38.8 gallons/acre or 3.67 billion acres which equals 14.85 million square kilometers. Unfortunately the entire US is only 9.1 million square kilometers.

This simple calculation should completely end the debate on biofuels but it doesn’t. Every honest engineer knows biofuels don’t work but what is worse are the subsidies from the federal government which have driven up fuel prices and created shortages across the poorest parts of the world. The inane policy of our government is actually killing people not to mention costing us money by increasing food prices and taxes.

Well we’ve found two alleged solutions which won’t solve the problem. This is progress, next time I will talk about nuclear.


One Response to “Energy and politics”

  1. AlexM said

    Your blog is interesting!

    Keep up the good work!

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