This is a short instructable. It's really more of a lesson than a DIY project, but the project comes at the end. I'd like to thank you all for reading this, and I hope you find it eye opening. So, here we go:

Imagine if tomorrow morning everyone in America cut their power/consumption by 30%. In 70 years how much cleaner would our country be? Would we have consumed 30% less, a little more, a little less? Would we have bluer skies and clearer water? How much would our coal consumption have declined? What about our dependence on foreign oil?

The answer to all the above questions is none, America's overall energy consumption would actually increase by 1%, and it would continue to outpace our current usage by greater and greater numbers. This probably seems strange, but it is pretty easy to illustrate using nothing more than a spreadsheet or a calculator if you have one laying around (or on your computer).

## Step 1: What the Deuce?

This doesn't seem like it could make sense? How could we use more energy by cutting our consumption than by doing nothing? Though it seems like there should be a change of about 30% in our overall consumption, that does not take into account one major factor about the human population. It is constantly growing. America is growing at a rate of roughly 1% per year. What does that mean?

At first look, one might assume that at a growth rate of 1% it would take roughly 100 years to double. It will actually take about 70 years. This is something we can calculate using a spreadsheet or calculator, however we will use the rule of 70 to simplify matters. The rule of 70 states that if you divide 70 by the rate of growth (in this case 1), it will give you the time it takes to double the thing that is growing. (70/1=70 pretty simple, eh?) Rather than verify this here, you are welcome to test it as an estimate for yourself or check it out on wikipedia.

This means that after 70 years the number of people in America will go from roughly 300 million to roughly 600 million. It's pretty clear to see how that can affect usage and consumption for a population.

## Step 2: A Closer Look.

So, what does this look like? I've attached a .pdf that has all the numbers I'm going to discuss, and hopefully it will be pretty easy to follow.

You can see on the main table that the left-hand column is dated for the next 70 years. This is followed by Population based on a 1% per year growth-rate. Next we have the population times the current energy consumption in Watts followed by the same number at 70% of that total. The final column is the total current usage, which we will use for comparison in our graph. The second table is the "sum of the watts used" over the course of the 70 years.

There are three important numbers to see here (the rest is mostly to make it a little prettier):
First, look at what happens in the Population column. After only 70 years the population doubles. This is after only 70 years.
Second, the total energy used: Notice that with the current population growth-rate even at 70% of the current power consumption the overall usage is about 1% higher than at our current usage with a stable population.

## Step 3: Getting a Little Crowded?

I want to take one more look at population. This may put population growth into a clearer view:

Imagine a bottle with one amoeba in it. Amoebae double every minute. After 1 minute there are 2 amoebae. After 3 minutes there are 4. At 4 there are 8, etc. After 1 hour there are 5.1617 amoebae, and the bottle is getting pretty full. Now it's natural for us to say that we would never let that happen. We would see the problem long before it happened, but at what point would we start to feel pressure? Would we feel it when the bottle is 1/2 full? 1/8 full? How much time would that have given them?

Luckily, we don't need an answer just yet. Just as the bottle was filling to the brim, some of the exploring amoebae came back with 3 more bottles. They celebrate their luck and rest assured that they have 2 1/2 more hours of trouble free growth. They are ecstatic.

How many more hours have they given themselves? Keep in mind it took them exactly 1 hour to reach fill bottle one. To fill the second bottle, it will take them only 1 more minute. What's worse, to fill the next 2 bottles it will take only 1 additional minute. That means that though they have quadrupled their available space, they have only added 2 more minutes before they are overcrowded again.

Hopefully this example has clearly demonstrated this fact: Every doubling of a population adds more people than the sum of all those who have previously existed. This is why conservation cannot save us.

## Step 4: Now What?

So, what do we do with this information? My instructable is not going to be condom usage. It's going to be about education. Using the same principles I have shown you we can see how easy it is for an idea to spread. If 10 people read this and each tell 2 people and that happens every day it could reach every person in America in the next 26 days. It could reach the rest of the world in only 3 more.

Right now we are on pace to have 13 billion people on this planet in the next 70 years. Whether we want to think about it or not, the world can only hold so many people. We can let nature take care of the problem through famine, drought, flooding and disease. We can let governments take care of it with war, oppression and genocide. Or we can change the way we think and realize that we may already be at 12:59 with only one minute left.

Share this. Talk about it. Don't let this information slip away. This is the looming disaster facing a population that won't begin see itself as a guest on a host that can only support so much.
Imagine a 70 year old pine forest. What do you have? A fire hazard!
well put. I've had this idea in the back of my head for a long time.
<em>Right now we are on pace to have 13 billion people on this planet in the next 70 years. We will have 50 billion in the next 200.</em><br/><br/>Every population forecast I've ever seen disagrees with you. Fertility rates are declining, in large and ever-increasing areas of the world.<br/>
I agree that we are not likely to see 50 billion for quite a few reasons (including the food/energy production that would require), but my models is in line with most predictions over the next 40 years, which is as far as many models predict. The notable difference is that UN projections expect a stabilization of the worlds population by the by the late half of the 22nd century. Even with that as the case, my predictions for consumption illustrate the same point. If we cut consumption by 30% but double our population, we are still seeing an overall increase of 40% consumption. This is definitely an illustration and not a projection, but I think the idea holds up.
The projections I've seen show population reaching a peak prior to 2100, perhaps as early as 2050, followed by a decline. We might reach 13 billion, though a peak of 9-11 is more likely. We'll never reach 50 billion.
Agreed on the 50. I'll edit that out since it's unimportant to thesis and seems to be a distraction.
Also you should take into account the rate of growth of life expectancy.