The US Air Force Research Laboratory (AFRL) shared a video on YouTube describing how the solar power satellite Arachne would work. 

AFRL Director Brig. Gen. Heather Pringle, quoted by Breaking Defense, said the critical design review of Space Solar Power Incremental Demonstrations and Research Project (SSPIDR) would be conducted this summer. 

SSPIDR aims to use an Arachne satellite that would convert energy generated from the sun to radio frequency and beam it down to a land-based antenna. Once the radio frequency hits the antenna, it will be converted to useable power. 

If SSPIDR is successful, it could one day give the US military a great advantage on the modern battlefield and an unlimited source of energy for forward operating bases. This will also allow for bases to power future weapons, such as lasers and rail guns. 

At the moment, the military requires massive supply chains and convoys to receive not just energy power generation equipment but also fuel to power generators at remote bases.