Escape Dynamics, a start-up in Colorado, recently tested a prototype of their new rocket engine. But instead of launching a rocket powered with typical rocket fuel, they launched it using microwaves by beaming power at the ship from an antenna. The system – which brilliantly incorporates a gyrotron, a power conditioning unit designed to supply highly stable current and voltage, and a modular power supply unit – could make space travel not only more affordable, but it could help save the planet by reducing the chemicals needed to launch into orbit.
Rockets powered with beams of power from the ground could be a game changer for the space industry. This type of technology will allow rockets to carry more cargo and be more efficient overall. “The key is moving beyond chemical rockets,” Escape Dynamics President and COO Laetitia Garriott de Cayeux said. “It’s been the same technology for over 50 years – chemical propulsion to escape Earth’s gravity. But there are two key limitations with chemical propulsion: The cost makes it prohibitive, and also, there’s a complete lack of routine, on-demand launch capabilities.”
Escape Dynamics envisions space travel a little differently than we’ve been doing it. They want to use a giant set of batteries to draw power from the electrical grid, solar panels, wind turbines or other alternatives. Once the batteries are charged, power will be sent to a set of modular, phased array microwave antennae spanning a square kilometer. Next, the antenna will shoot a microwave beam at a heat exchanger on the spaceship. The heat exchanger will heat up the hydrogen in the fuel tank, which is what powers the rocket on the ship into orbit.
Because the power for the rocket comes from the grid or other alternative sources of power, money is saved by not using rocket fuel. It is also a much more efficient way to power a rocket. A rocket’s efficiency is measured by its specific impulse — the ratio of how much thrust a rocket produces to the “weight flow of its fuel.” Chemical rockets have a specific impulse of 460s. Our current boosting technology doesn’t have enough power to get a rocket into orbit, so right now, rockets need more than one boost to get into space. Using this new type of external propulsion, Escape Dynamics thinks that they can get a specific impulse greater than 600s, big enough that only one boost will be required to reach orbit.
Images via Escape Dynamic