"The "energy receiver" (gravitational energy converter) had been built by Tesla himself."
http://waterpoweredcar.com/teslascar.html
"A gravitational wave will cause the distance between two test masses to oscillate. A local observer will detect this as an input of kinetic energy into the masses."
https://physics.stackexchange.com/questions/387525/do-gravitational-waves-carry-energy#500271
"If you know the frequency of a graviton, then hf is its energy. But you do not need E=hf to calculate the energy of a gravitational wave, or of an electromagnetic wave. Classically, the energy content of these waves is proportional to the square of the amplitude."
https://www.physicsforums.com/threads/energy-of-gravitational-waves.857922/
"Not only do gravitational waves carry energy, but that energy can be transferred into systems made of normal, everyday matter."
https://www.forbes.com/sites/startswithabang/2020/05/08/ask-ethan-can-we-extract-energy-from-gravitational-waves/?sh=e7fae51211b8
"The power emitted in gravitational waves for everyday objects is absolutely negligible. Even the total power emitted in gravitational waves by Jupiter as it orbits the Sun is only a few kilowatts! In fact, there are only a handful of binary systems where there has ever been evidence for gravitational wave emission witnessed."
https://astronomy.swin.edu.au/cosmos/g/gravitational+waves
"The gravitational waves emitted by pulsars are almost monochromatic, i.e., have a single frequency, which decreases over time due to the emission of energy in the form of gravitational and electromagnetic waves."
https://www.einstein-online.info/en/spotlight/continuousGW/
"We can generate a rough expression for the energy in gravitational waves, when the wavelength is much smaller than the degree of curvature of the spacetime. This energy is an average energy density over spacetime volumes; the dimensions of which are larger than the wavelength, but much smaller than the background curvature scale."
https://steemit.com/science/@diracdnb/energy-in-gravitational-waves
"The energy of gravitational waves is a fundamental problem in gravity theory"
https://arxiv.org/abs/2109.06864