March 12th

What’s wrong with this picture?


This presents the total energy production in the Extreme Environmentalist scenario, in which the player levies the maximum taxes on carbon emissions. This quickly drives fossil fuels out of business. But it also creates a new problem, made more obvious by zeroing in on nuclear energy production:



According to this graph, the loss of fossil fuels triggered a crash program in building nuclear power plants; in just three years, we roughly tripled the supply of nuclear power. That’s preposterous, because you can’t build nuclear plants that fast. The same thing applies to solar energy or any of the renewables: you simply can’t increase supply that rapidly because of the high capital costs they require.

The obvious solution is to insert some negative feedback into the supply algorithm, based on the rate of increase of supply. Here’s the negative feedback system I chose:
double pastSupply=tc.getPreviousValue(energySource);
double supplyGrowth=(thisSupply-pastSupply)/pastSupply;
if (supplyGrowth>0)
thisSupply*=Math.exp(-supplyGrowth);

Pretty straightforward, right? If the supply increases, then we scale it back by a factor commensurate with the magnitude of the growth. Here’s what the results look like in the same scenario as above:



Nuclear still shoots up very quickly, and then dies off just as precipitously, even though the negative feedback is very strong. Part of the problem arises from the algorithm used, which numerically integrates the total supply over the price range required to meet demand. I’m scaling down the individual steps in the integration, but the number of steps increases to meet the demand, so we still get steep rises.

What to do? If I boost the negative feedback, it chokes off the growth due to research, which should be strong. If I apply the negative feedback AFTER the numerical integration, I end up preventing supply from meeting demand.

I’m tempted to do just that. I had been relying on rapidly rising prices to choke the economy when taxes are too high. But what if I instead throttle supply growth, and pass the impact of insufficient supply on to the GDP? It’s a possibility...