2 + 2 ≠ 5

Suppose you had a planet, let's call it Planet Worth.

The planet could sustain a certain amount of life, and would be run by a particular species. We'll call them Ruinians. The Ruinians have for many thousands of years managed to survive reasonably well; they have developed agriculture, democracy, methods to enhance their fertilty, methods to prevent fertility. They have had some wars and diseases, sure, and at times they have had some pretty serious setbacks. But by and large they have increased in number, they have got healthier, live longer, consumed more and find themselves now at a point where they are starting to challenge the ability of Planet Worth to provide them with resources quite as easily as in the old days.

The Ruinians have not been totally unaware of this situation developing and many have started to make some noise about it. But some are making noise -albeit with good intentions - about the wrong things. They are talking about choices, but some choices aren't being put on the table.

Time to stop talking in riddles.

The planet has some good, useful stuff in it. Like coal, and oil and gas. The Ruinians know they aren't going to last forever (known it for a century or more), and they know that despite this they are consuming these materials at an ever increasing rate. Our old friend supply and demand tells us that when Ruinian Crude hits $108 a barrell, there's a fair chance it's because lots of people want it. Back in economics class we learnt about substitute products, and how they start to become attractive when the original gets scarce. And the petrol Mr and Mrs Ruinian put in their tank is starting to attract some substitutes. Enter biofuels.

Now the only trouble with biofuels is that they don't grow on trees(!) You have to plant huge fields of them, you have to convert and refine them to make them into usable fuel. And if you are using that land for fuel then you can't use it for anything else.

Remember the arguments for curtailing global population growth that I was banging on about earlier? Now we have a second reason to need less people - you can't make people and biofuel crops and feed-crops all co-exist in the same field. Not even Doctor Who has that one sussed.

Another thought, that makes the 'Westernisation' of Planet Worth tricky. Western Worth is hooked on animal produce - they love their hamburgers - and, you guessed it, you need land to raise animals. No, not the lovely farmyard scenes from the nursery books, I'm talking hectares of land turned over to cattle herds to serve the growing millions of fast food lovers the world over. Space. So little of it. So many demands for it.

Now, in the Ruinians newly enlightened times it shouldn't take much working out that if they want to have enough food and enough energy for everyone then they have to:

• make sure that 'everyone' is not a growing number
• replace the fossil fuels with renewables, including setting land aside for biofuel crops, and
• stop gorging themselves on inefficient foodstuffs. Using land to raise meat uses 3 times more resources that raising crops for direct consumption

I think the Ruinians have a good chance of pulling through, because they did their sums and realised that you can't get a quart out of a pint pot; you can't make 2 + 2 = 5. They have a fix on their planet's value.

Do you know what your Planet's Worth?

http://www.guardian.co.uk/environment/2008/apr/05/biofuels.food
http://www.vegsoc.org/info/why%20its%20green%20final%20small.pdf