Maybe, but there is the internal buffer. Also, most I/O happens in files not consoles

std::endl is used in output streams in C++ to end the line, using the os specific line termination sequence, and flush the buffer.

The later one is a performance issue in many cases, why the use of "\n" is considered preferred

Have you ever heard of case of overheating hard drives within the last decade?

If you ignore the impact on the environment, fertilizers, CO2 production by machines required to grow that stuff. Sure, then it is just ineffective solar.

In reality it is a environmental nightmare.

Edit: some more insight https://www.epa.gov/sites/default/files/2014-12/documents/environmental_challenges_associated_with_corn_ethanol_production.pdf