Forget Oil - Contest: Find a substitute for oil.

[Axeil]

Ok, like the title says let's forget using oil, natural gases, etc. Though forget "substitue" in the title - let's turn oil into a last resort substitute. I challenge everyone on this forum to find a better, more ecofriendly and efficent resource. If you can figure this out...well...you've helped alot of people.

[Dark Mind]

Hydrogen.

What do I win ?

And welcome aboard Hypography .

[Tormod]

All natural gas is not non-ecofriendly! If we could build engines that run on hydrogen (Although prices must come down) we'd be a lot better of ecowise.

However, what about solar cells, wind power, hydropower (waterfalls), tidal power? There are a lot of options being explored and used already.

[Dark Mind]

Originally Posted by Tormod

However, what about solar cells, wind power, hydropower (waterfalls), tidal power? There are a lot of options being explored and used already.

All of these come down to gravity . (Yes, even the Solar cells... Think about it...)

Gravity is the only force I know of that never loses energy. Harnessing it's full potential seems rather difficult, and probably not feasible or cost efficient for family owned transportation vehicles .

[pgrmdave]

The problem with hydrogen is that it takes a LOT of energy to get it into a usable form. Wind and solar energy are probably the best ways to go, their biggest ecological effect is their footprint.

[Tormod]

Originally Posted by Dark Mind

All of these come down to gravity . (Yes, even the Solar cells... Think about it...)

I am thinking about it - how do solar cells come down to gravity? AFAIK the major problem with solar cells is that they are expensive and have a poor conversion rate.

[UncleAl]

Human liposuction waste. Figure an overall average equivalent to 10 lbs each from 2/3 the population of the US alone. That's two billion pounds. Burn it for fuel, feed the poor, grease the skids of civilization. Over a hundred years you would retrieve 200 billion pounds from annual harvest. Render corpses for their body fat and the numbers go way up.

Why are we burying our free energy future?

[HydrogenBond]

They used to burn garbage for energy but nobody wants co-gen in their backyard. This the social problem with most renewable energy. It is funny that nobody mentioned nuclear fusion. Progress is slow and nobody has be faith it will be soon. Hydrogen gas sounds good and should be interfaced to other renewal energy like solar. There are bacteria that turn nitrate in nitrogen gas, maybe bacteria that make hydrogen. We pull a large solar powered bacteria farm behind us that generates hydrogen for our car.

[UncleAl]

Grow coelacanths in the now sterilized Grand Banks fishery. They use body oil for flotation not swim bladders. Coelacanths are finny oil wells. The left-over protein can feed Welfare mothers. Nothing bothers a coelacanth and survives the attempt - armed and armored. They're big, too.

http://www.mazepath.com/uncleal/coel.htm
http://www.dinofish.com/cimages/coel03b.jpg
http://www.jonchristianryter.com/IMA...nth%5Br%5D.jpg
Google Images
coelacanth 5350 hits

The inevitably aborning coelacanth oil crisis is not Uncle Al's problem.

[CraigD]

Originally Posted by Dark Mind

All of these come down to gravity . (Yes, even the Solar cells... Think about it...)

Good, challenging riddle, Dark Mind. Of course, solar cells generate electricity from light which is generated by fusion which as triggered by the gravitational collapse of the solar nebula. However, gravity is the source of solar energy only in the same way that the force of ones finger muscles are the source of the energy produced by a struck match. Small expenditures of energy (eg: collapse of the solar nebula) can trigger the release of larger amounts (eg: solar output) .

Gravity is the only force I know of that never loses energy.

Precise use of Physics terms are essential when making statements like this. Gravity is a force. Force applied over a distance (eg: lifting a stone against the force of gravity upon it) is work. The potential for work (eg: a lifted stone) is energy (energy and work have the same units) which can produce work (eg: dropping a lifted stone).

“Undesired” work is friction, and is responsible for “losses” in the production of energy by work, and the production of work from energy. Because gravity can act over a great distance, the energy produced by that force over such great distances can occur in the nearly friction-free setting beyond the earth’s atmosphere, making it a very efficient, but still not perfectly efficient, so it is, “lost” by such systems as the solar system.

Harnessing it's full potential seems rather difficult, and probably not feasible or cost efficient for family owned transportation vehicles.

It’s pretty easy to harness the potential of gravity. For example, spool a cable around the axle of some sort of wheeled vehicle, pass the free end over a pulley affixed a manageable height above, attach to a manageable massive object, wind, then release. This “gravitymobile” will exert a force averaging slightly less than the force required to wind it, over the same distance require to wind it. Like the mousetrap vehicles so familiar from the ad link on scienceforum’s main page, such a vehicle can reach a surprising speed, but isn’t something most of us would feel comfortable driving in rush hour traffic.

As this illustrates, a problem with gravity energy systems is that gravity is a very weak – the weakest of the 4 fundimental forces – makes for very low energy/mass densities compared to more traditional systems using gasoline, electric batteries, etc.

When it comes to collapsing stellar nebulae to ignite stars, gravity is an excellent force. For automobiles, it’s not so good.