Back in the early 1990’s, I studied Environmental Sciences for a while, at FIU. While there, all the students had to get with the professor for a one-on-one and pick a project that would have a long term positive environmental impact. This professor, who shall remain unnamed, was very strict, and was very “Green”, at a time when being Green wasn’t as understood as it is today. Initially, I chose next generation nuclear reactor technology as a stepping stone to fusion power. I was shot down immediately. Anything that left as a by-product active emitting radioisotopes was a non-starter. A “big picture” guy, I came up with another high-tech endeavor: Microwave Beamed Power from geosynchronous orbit! “Hmmmmmm” said the professor. “I’ve thought this through, but it’s a good exercise for you. I approve!”.
Using an adequate amount of physics, formula, and math, I went about demonstrating how big such a satellite would have to be, how it wobble to maximize solar cell exposure to the Sun, and how the beam would need to pulse a way through the atmosphere, taking heavy efficiency losses along the way. It was a still a net gain, generating significant power for a structure the size of a few dozen football fields (my starting point). I thought was done. “No, no, Jared! You’ve just begun! Now you get to study something new! Now you get to study the environmental effect of rocket fuel and rocket launches, as well as payload constraints for the various types of launch, culminating with the Space Shuttle, the current lift favorite”.
Study I did, and when I put together how much the orbital power generation facility would weigh, I estimated an agreeable five thousand metric tons, I then set to work to see how long it would take to launch the components of such a structure into orbit. At the time, the heavy lift leader was the Saturn V, and it could lift 140 metric tons. It would take thirty-five launches of the Saturn V to put the power generation station up, and the entire Saturn V program only launched twelve successfully, at a cost of almost $50 billion in 2020 dollars. 12 x 140 metric tons = 1,680 metric tons. For $50 billion. I was crushed, and told the professor. “NO! You aren’t done! You didn’t get to the good part! Forget about the money! This isn’t a class about Economics, this is a class about Environmental Science!” He then had me research what was in the fuel of the Saturn V, and then the Space Shuttle. Saturn V uses RP-I . . . a green-house gas emitting fossil fuel. The Space Shuttle uses Hydrolox and solid fuel boosters. and produces nitrogen oxides, aluminum oxide, hydrogen chloride, carbon soot, CO2 and can contribute to acid rain. Hydrolox, while produces mostly water, it also produces NOx, while trace amounts compared to the whole, when multiplied by millions of liters, adds up to significant amounts. After looking at the huge quantities of harmful emissions, I realized the Professor’s point regarding huge numbers of lunches of heavy lift rockets. I was determined then to help discover a way to make frequent launches to LEO have negligible environmental impact, and thus the seed of Orbital Bridge was born.
Authored by: Jared Freedman, Founder, Orbital Bridge