A new estimate of the amount of energy needed to visit the stars suggests we won’t have enough for at least another two centuries.
Marc Millis’ mathematician’s, former head of NASA’s Breakthrough Propulsion Physics Projecthe, endeavored to use massive amounts of data for the question whether humankind will embark on space Odysseus anytime soon. His answer is a ‘NO!’
Millis looked at the amount of energy the US has used to launch the shuttle over the last thirty years or so, as a fraction of the total energy available to the country.
He assumes that a similar fraction will be available for interstellar flight in future.
A mission is a human colony of 500 people on a one-way journey into the void. He assumes that such a mission requires 50 tones per human occupant and that each person will use about 1000W, equal to the average amount used by people in the US in 2007.
From this, he estimates that the ship would need some 10^18 Joules for rocket propulsion. That compares to a shuttle launch energy of about 10^13 Joules