## October 8th

I’m now getting into serious system balancing. This is one of the toughest parts of designing any big simulation like this and it’s something I’m particularly good at. But today I made a change that is going to cost me. I decided to change the basic unit of energy from an exaJoule (10**18 joules) to a gallon of gasoline equivalent. That’s actually something of a nonsense unit of energy: other forms of energy are used in such different ways that converting them into the equivalent in gallons of gasoline is a bit of a stretch. But this has one thing going for it: when I say that the price of energy is \$4.00 per gallon of gasoline equivalent, everybody immediately gets it. If the price reaches \$10 per gallon of gasoline equivalent, everybody knows that’s expensive. If instead I present it as, say, \$75 billion per exaJoule, (the equivalent value), people just won’t get it. So I have to make the change.

Unfortunately, this requires me to revise every part of the simulation that measures quantities or prices of energy, and that stretches a long way. So I’ve been trudging through the database, revising numbers. The situation is seldom so simple that I can merely multiply or divide by 7.58 (the conversion factor). In many cases I must recalculate coefficients. I think that I’ve got the energy production values all recalculated correctly, but now I’m moving on to industrial production. This raises two problems. First, I have to recalculate industrial production because it uses the energy price as one of its inputs.

But second, I realize that I need a technology factor in industrial production. That is, the value of industrial production rises with technology. If we were still stamping out Model Ts and primitive radios and cotton clothing, industrial production would not be that high. Technology has permitted us to make products that have very cheap inputs but are very valuable – like iPhones, for example. Some sand, a few grams of various metals, an ounce or two of plastic, and you’ve got something worth a few hundred bucks.

The difficulty with assigning a factor to “general technological advance” is that I have no space for it. I already have five broad categories of subsidy and five subsidiary technologies. The system doesn’t permit more than five (it’s complicated, but arises from input considerations.) I think I might be able to get away with making “general technological progress” dependent upon a sum or combination of multiple technologies.

More thinking necessary.