Last Topic: 1:58:11am, 05/16/2017
Last Post: 6:37:15am, 02/01/2022
There is a fundamental misunderstanding here of how mining and its energy consumption works. The statement that it takes infinitely more energy per transaction is completely wrong, as well as the complexity of the hash required increasing per transaction. That's not how the relationship of mining difficulty and the blockchain works.
The length of the chain is wholly irrelevant to the computational power required to find a valid hash for the next block. That is controlled by the mining difficulty, the higher it is, the more random guesses are required to find a valid hash, meaning more computational power is required. This difficulty is adjusted dynamically based on the average time it takes for a solution to be found for a new block, which is every 10 minutes in the case of Bitcoin. The only thing influencing this difficulty is the existing computational power on the network. More people turn on more hardware, the average block time decreases, and the difficulty goes up. People turn hardware off, the average time goes up, and the difficulty lowers. It's entirely possible for the chain to run permanently on one person's CPU taking 50 watts. The difficulty would adjust down until it averages 10 minutes again, it doesn't matter if the chain was petabytes of data.
Of course, the reason that isn't the case is because of Bitcoin's price making mining profitable to where many people bring in more hardware to get a piece of the pie, which is what drives difficulty ultimately.
The only thing always scaling is the storage space requirements of syncing the entire chain to run your own node, but progress of storage technology will far, far outpace BTC's needs so that doesn't matter.
Finally, you don't mine Bitcoin on a CPU or GPU anymore as there is much faster specialty hardware called an ASIC now that raised computational power, and therefore difficulty, up so much that a GPU isn't fast enough to profit anymore. ASICs are plenty profitable, however.
---
My previous signature randomly started getting autoflagged after years of use. Now I have none. Thanks, autoflag.