A document was found in the digital library called A Guide to Free Energy Devices and Systems Schematics and options from 50 researchers based on alternative ways of generating energy, such as from a vacuum (with high electrical potential, naturally) and antigravity as a side effect as antigravity as a side effect sounds
On the subject of how long ago there have been inventions on alternative energy with higher efficiency than mankind has now. But the cheaper to build cheaper to sell scheme is unprofitable in a world of victorious capitalism👌

https://x.com/ronin19217435/status/1764534984927273079?s=20

The manual in pdf format:
https://drive.proton.me/urls/M3T5P8F37C#DDLjmxqTI42c