Sunday, March 4, 2012

Alternative Energy

With gas prices spiking again it there has been talk of how to bring them down. If you follow politics (I do as the government has a much bigger impact on my life than most things) then you may have heard of President Obama's suggestion to create fuel from algae. Now true to form the Republicans started bashing President Obama on this supposedly stupid idea claiming it won't work and won't make a difference. The truth is it would work and would make a difference. Now this isn't' the only idea out there on how to fuel our future but is the most recent. So with this topic I decided to cover some of the ideas that are out that since oil is a finite resource  despite what one party would suggest and we will eventually run out. This way people can have a good understanding of what the options are and have reasonable knowledge about them. Side not I once asked an oil geologist about how much oil the earth ever had and got the following about 15 years ago so the values may be different now and I don't know if these include non traditional sources like tar sands and shale:

  • Approximately 6 trillion total barrels of oil existed
  • Approximately  3 trillion of that 6 trillion are recoverable with current technology
  • We have consumed  approximately  1 trillion in the last 200 years, most in the last 50 years at an ever increasing rate.
  • OPEC lies about their reserves.
The battery powered car
First off this means nothing. A battery powered car is really only as clean as the source that provides your electricity. Granted coal, and natural gas power plants are a whole lot more efficient than your small internal combustion engine in your vehicle so even powering an electric car with electricity from a coal plan would probably be much cleaner. This is most because a really good running vehicle engine is capable of a max 30% or so efficiency. This means that you use at most 30% of the total energy in the fuel for useful work. The large stationary engines used in power plants are about twice as efficient meaning they get twice the usable energy from from the same amount of fuel. Also handling pollution from one stationary large source is much easier than from many small moving sources. Right now the biggest obstacle for electric cars are range and recharge time. The best ones now claim 100 miles on a charge that takes 8 or so hours from a special outlet. Granted this does cover most people's daily driving habits. Also this wouldn't require additional power plants as most people would be charging their vehicles at off peak times (at night when power demand is low and generators that can be stopped are) when there is extra generation capacity.

There are 2 primary forms of solar energy photoelecrtic and solar thermal. Both can be used to produce electricity to do useful things with like power a car with a rechargeable battery. I have head lots of people complain that there is no way we could ever get enough power from these to power our planet. These people are wrong. The truth is if 1% of the entire planet was covered with 1% efficient solar panels would would be able to meet all of our current power needs. This isn't a number I just made up but is are real figure from NASA where they state that we receive 10,000 times the energy from the sun than we actually use. Now given that most solar solutions are more efficient that 1% (really good solar cells are about 40% efficient and cheap crappy ones are usually at least 5% efficient) we could easily meet all of our power needs. Solar thermal can be used to generate power even when the sun goes down as they use molten salt to store the heat so solar can work even when it is dark out. The setup for this is the solar power tower where mirror focus light onto a tower. 

Good idea in theory when you do it like the Brazilians do but when you do it like we do in the US and make it from corn it is one of the dumbest things government has ever done. I plan on writing a couple of articles specifically on ethanol eventually where I will really go into detail on it as it is the favorite bio fuel.

Bio oils
There are a number of things that can be lumped under this heading such as the bio diesel made from used vegetable oil (or straight vegetable oil), bio diesel made from soy beans, and bio oil. that is refined into fuels. They are all chemically very similar. This is where President Obama's plan to make fuel from algae falls. This group would be the least painless for most people as it requires no change to our current infrastructure. You can refine bio oil into the correct type of fuel to use in your vehicle or what ever. So lets look at a few select options in the category (I can't include all of the different options there are too many):
  • Algae - This shows some promise for making bio oil even in crappy climates like Minnesota. Granted it would work better in warmer sunnier climates like Florida or California. Basically what is done here is algae is grown in enclosed vats  of water. When the vat is full the algae is scraped off  and pressed to get the oil out of it. The left over bits of algae can the go off and be used either as a fertilizer or feed into some other processes or disposed of in some appropriate manner.
  • Thermal Depolymerization - This is another promising solution as it would work with just about any organic material. You can use things garbage, bits left over from animal processing plants, saw dust, tree trimmings, leaves, switch grass, or basically anything made from carbon. Under high heat and pressure (add in some water if your source material doesn't have enough) you turn carbon based things into oil. This oil can then be sent off to be refined into the same things we make from crude oil from the ground like fuels, plastics, fertilizers, industrial chemicals. 
  • Fischer-Tropsch Process - This is a similar process to thermal depolymerization and is part of the gas to liquids process to produce liquid fuels and other hydrocarbons from organic material. It is a process that works as the Germans used in during WWII on an industrial scale to fuel their war machine. They were using coal as the source material but you could feed it any carbon based material and get the same results.
  • Vegetable Oil - I think this is great using wast veggie oil to power a diesel vehicle. Here you basically get used fryer oil from restaurants (they may give it to you free since they have to pay to dispose of it) and you go an burn it in your diesel vehicle. It seems like a good use of something that was just going to be thrown away. If you are interested in doing this just do a Google search and you will get more info that you need to get started. It probably wouldn't work to fuel every diesel vehicle as there just isn't enough wast vegetable oil but it would cut demand for diesel.
If you think this is going to happen you are kidding your self, and no I don't mean because of the Hindenburg. The biggest problem is hydrogen is that it doesn't exist in a free state on our planet. You need to make it from something and you will never get the energy out of it that you put into making it. Lots of people think that this is the water powered car, if you are one of them you have been fooled, this won't work because of the Laws of Thermodynamics (I should do a post on this myth some day). Basically there are 2 ways to make hydrogen either use natural gas and do some steam reformation on it or use massive amount of electricity to do electrolysis on water, either of these options takes way more energy than you will ever get back out of the fuel so why not just have natural gas or electric vehicles instead and cut out all the losses of making hydrogen. Other than the energy loss (hydrogen is really a poor carrier) hydrogen is a pain to transport. Again here I am not talking about explosions but it has this nasty ability to cause embrittlement in all sorts of metals, and we currently don't have a distribution network for it like we already do for the things required to make it (natural gas, or electricity). So can we just say this was a stupid idea and quit wasting resources on it.

Non-Traditional Oil
This is probably the worst solution as we could go after more shale oil, tar sands or just convert coal to liquid fuels. It would work until it becomes too expensive to do but it would buy some more time to get better solutions working.

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