One thing about energy losses during conversion processes, we can burn part of our feedstock that’s in an inconvenient form to provide the energy to transform the rest of it to a more convenient form. So if we convert coal to liquid fuel, the energy to do so comes from more coal. So even though we lose lots of energy in the conversion process that energy doesn’t neccesarily have to come from some other source…it’s just that we end up with less usable energy than we would if we could have used the original form.
So if we’re going to power our cars via coal, it might make a lot more sense to burn the coal at electrical generating stations and run electric cars rather than use the coal to create liquid fuel and run IC cars, or use the coal as solid fuel for steam cars.
I see your logic, but that would require a substantial changeover to all electric vehicles. If we could make gasoline, or a hydrocarbon fuel that could be used in existing vehicles with minor modifications, it might be a good interim solution.
South Africa makes fuel from goal at about $50/barrel.
Probably the greatest potential in grown fuel is going to be [bio-diesel from algae](South Africa makes fuel from goal at about $50/barrel.). We are currently making it at 4,000 gallons per acre per year and that number is expected to grow as the technology advances. It burns cleaner than regular diesel and the process uses CO2 from power plants. We are also experimenting with jet fuel (which is basically the same thing as diesel).
The future is here but nobody seems to know about it.
Levers change the range of motion and the force exerted, but they don’t change the amount of energy in play at all. You will only ever have a ham-sandwich’s worth of energy available - with a gigantic enough lever you can either move the earth a tiny tiny bit or move something tiny a long long way - but you will never be able to move the earth a long distance - that awkward first law of thermodynamics again.
Levers, pulleys, ramps and the like don’t let you create energy - they just let you use mechanical advantage to transform small long-duration efforts into large short-duration ones, and vice versa.
Would it possible to run existing IC engines on something other than hydrocarbon-based liquid fuel? Sodium, for instance, reacts magnificently with plain ol’ water – could that, or similar reactions, be harnessed as fuel?
I’m trying to think of what elements actually are flammable – you need stuff that burns, as hydrogen and carbon do. Not sure if sodium is flammable in the sense that you can light it like charcoal (or is it?). Magnesium is flammable, IIRC (flash bulbs in cameras). Potassium, too, right?
Turning that stuff into a handy-dandy ready-to-pump liquid may be another matter altogether, of course. Like I say … wild hair.
Well, it would probably be pretty radically different from a standard IC engine, but I believe things like elemental boron have been proposed as fuels, so there’s no reason why you couldn’t use a sodium/water reactor as e.g. a heat source for a steam car. The practicalities of weight, energy content, toxicity of reaction by-products, cost of materials etc. are usually what make alternative systems tricky.
Now that I think a little more on it … IIRC, what you really need to run unmodified IC engines is a combustible vapor. That is, if what’s getting sprayed into the cylinders can be considered gasoline “vapor”.
Does that open the door, conceptually, for gaseous fuel? Get hydrogen from fuel cells, have a system that leaks a little H into the cylinders, add spark, and go. Too risky? Too much of a PITA to handle/distribute compared to liquid gasoline (or does the use of existing fuel cell technology mitigate that somewhat?)?
I know propane cars (for instance of gaseous fuel) are a technological possibility … but you don’t want to get in a wreck with a propane car! I am assuming substituting some other gas for propane doesn’t increase the safety factor very much.
There are plenty of fleet vehicles that run on CNG–compressed natural gas, which is methane. Of course we could run IC engines on gaseous hydrogen, or methane, or ethane, or propane.
The trouble with fuels that are gases at room temperature is that they take up a lot more space than liquids. So you have to compress them, or refrigerate them, or generate them on demand. So you could have metallic sodium, drop it into water and generate hydrogen gas on demand, and then burn the hydrogen.
The trouble with the sodium angle is that while sodium isn’t an uncommon element, it takes quite a bit of energy to refine it from sodium compounds into sodium metal.
Pretty much. Hence the popularity of cheap simple systems like wood gas and the like.
And yes, with sodium, boron and the like you’re basically using the metal to transport energy from the refining plant to the vehicle. You still need a lot of fossil, nuclear, hydro, solar or whatever energy to power the purification.
There was an article in Discover about guys that were doing this with turkey offal. It was a lot more than just a vat, and they were still trying to figure out how to make it commercially viable (i.e., make a profit).
I found the article here. The company has a web site at http://www.changingworldtech.com/ but it doesn’t give a clue as to how profitable they are. Looks like part of the business model is to license the technology.
One could use hydrogen peroxide, more typically used as a monopropellant rocket fuel, or an oxidizer for a secondary reaction. Hydrogen peroxide doesn’t “burn” actually, it decomposes into water and oxygen with a great deal of released energy. The oxygen can then feed combustion of something else. Hydrogen peroxide is interesting in being both a fuel in its own right and a terrific oxidizer.
Given that the actual peroxide decomposition produces only water and oxygen as waste products, it seems attractive as an energy storage medium. There have been proposals for automotive use of the stuff, but the safety concerns are, ummm, considerable. Just imagine vehicles driving around with tanks of high concentration hydrogen peroxide. The medicinal peroxide you get at the drugstore, and perhaps get a little skeevy about using is a 3% solution.
Like the aluminum-H2O cycle? You convert metallic aluminum into aluminum hydroxide and water. When the aluminum is consumed, you replace the battery.
There was also the zinc-air battery. A solid fule for cars
IIRC, the energy needed to produce metallic aluminum from bauxite (?) is non-trivial. May be worth it, though … don’t have the cost-benefit analysis at the ready.
Also, how do these batteries stack up against existing hydrogen-fuel-cell technology? IOW … which of these batteries is the better mousetrap?
If I remember correctly from the article, one of the roadblocks was that meat plants are still allowed to sell offal to make feed for cattle and other ruminants. Perfect way to transmit Bovine Spongiform Encephelitis, if it gets into the food chain. So, the thermal conversion/de-polymerization people were having to pay for truckloads of offal instead of getting it for free or being paid to haul it away.
They were also having problems with people filing odor complaints against the plant. Even though many of the complaints were filed when the plant was not running, they were still forced to upgrade their equipment to appease the townspeople.
Last thing I heard was that the company was focusing its efforts in Europe, where plants are not allowed to sell their offal for feed, and the plants are more than happy to pay to have it hauled away.