A few days ago, the Atlas V rocket launched a military mini-shuttle X-37B into orbit around the Earth. This is the sixth successful flight of a “spacecraft”, as this reusable spacecraft is called, and its mission is particularly intriguing. The X-37B usually performs tasks on military programs that are classified, but not all. This time, the mini-shuttle launched a prototype photovoltaic module to transmit solar energy converted into electricity to the ground in the form of microwave radiation.
The US Marine Research Laboratory (NRL) is conducting an energy transfer experiment for which the PRAM (Photovoltaic Radio Frequency Antenna Module) module has been developed. The prototype with a radio frequency antenna is a block with sides of 30 cm, equipped with conventional photoelectric converters (solar cells), which convert the sunlight falling on them into electricity.
How it works? The energy received from the module in orbit is converted into microwave radiation and transmitted to a receiver located on the ground. The receiver is also a generator that converts microwave radiation into electricity and sends it to consumers. The energy received in space can be transmitted to the earth by a laser beam – with the help of a powerful infrared laser, but in the Earth’s atmosphere it is possible to transmit without significant absorption only microwave radiation, notes New Atlas.
The photovoltaic radio frequency antenna module compared to a 30 cm ruler
The NRL laboratory experiment aims to study in real conditions the process of energy conversion, the thermal characteristics of the processes and the efficiency of the technology with the available prototype. Such methods of transferring energy from orbit, where the sun shines 24 hours a day and at an optimal angle to the solar panel, can help provide electricity to remote parts of the planet, such as military bases or disaster areas.
At the next stage, based on the results of PRAM, a fully functional prototype system installed on a satellite will be developed. It is also planned to create a channel to send energy to Earth. Undoubtedly, it can take decades to turn this technology into a large-scale energy source. This will be an expensive solution, but in some scenarios, the rapid deployment of power plants on Earth with an unlimited energy source can be commensurate in cost.
