A wise person will evaluate as many options as they can when they purchase a car. Typically, a person will buy the least expensive car that meets all their requirements. A smart buyer will also include the expected cost to maintain the car over the planned out-years of ownership. This total cost gives a much better estimate of the true cost of ownership.

In the year 2014, the world population increased by about 81 million people. In that same year the total human population of 7.1 billion people used about 5.4e20 Joules of primary energy. That is, each person consumed on average 7.6e10 Joules of energy. Now assume that each of the newly added people will live for 75 years and that they consume this same amount of energy each year of their lives. A reasonable assumption. With this, we know that their total lifetime primary energy expenditure will amount to 4.56e20 Joules. Interestingly enough, the added energy demand is almost equal to the total current energy demand. Perhaps a bit like your car expenses. More interesting is that this additional energy cost for the out-years will likely be added to by the same amount on the next year. And the next year.

Is there enough energy available on the Earth to maintain our continually increasing, ever energy hungry population? Can we support the energy cost of keeping the Earth’s population at its desired technological level? Can our planet afford the out-year demand upon its energy budget?