Guilt free petrol only 5 or so cents away!
Currently the human race is doing a very good job of screwing up the environment by dumping heaps of greenhouse gases into the atmosphere. The one with the largest effect being carbon dioxide, which has increased in concentration by 32% since the start of the industrial revolution. So it might be a good idea to do something to get some of this stuff out of the atmosphere. Carbon sinks are a way to do this.
Basically a carbon sink is anything that removes carbon from the air and locks it up. This can be as simple as growing trees or as complex as blowing mountains apart with hydrogen bombs to make carbon absorbing gravel. Other possibilities less drastic than nuking mountains include seeding the southern ocean with iron to increase plankton growth and changing farming practices.
Creating carbon sinks costs money. At first the cost may be low as less expensive options are used, such as growing forests on marginal grazing land, but to do it on a large scale might result in a cost of around $65 dollars per ton of carbon absorbed, according to some estimates. Assuming this figure is correct, then removing the carbon dioxide produced by a coal power plant would cost enough to increase the price of that electricity for consumers by over a third. This would make coal power more expensive than wind or nuclear.
However, coal is very cheap compared to oil. The costs of trapping carbon released by burning oil are much cheaper in comparison to the total price. Currently oil costs about $740 per ton. Since it is about 85% carbon, then the cost of absorbing the carbon dioxide produced by burning a litre of petrol in your car would only be about 5 cents. In other words, a 3.5% increase in the current retail price. If we tacked this price onto each litre of petrol sold it should be enough to pay for the removal of the carbon dioxide it creates. Now I suppose a lot of people don't want to pay an extra 3.5% for petrol, but I have also noticed that a lot of Australians were willing to pay a lot of money to help Asian people who were hit by a tsunami, so I think Australians are quite interested in saving people from being inundated by sea water. And just think, for only an extra 5 cents a litre you could fill up your tank and drive entirely guilt free.
Unfortunately, these days a lot of energy is spent wringing oil out of deposits and the oil we get tends to be getting ickier and ickier and more costly to refine. It's not like the good old days when you could poke the earth with a giant needle and the black blood would come bubbling up by itself. Nowadays we oil junkies have jabbed the earth so much we can almost never find a good vien and when we do we often have to force the blood out. The additional cost of capturing carbon released in this process might increase the cost to 7.5 cents per litre.