One of the values of bitcoin is the price miners get for it. If they lose money on selling their newly minted bitcoins they won't sell. So it's related to power prices, the difficulty of mining a new coin.
That sounds like a restatement of the "labor theory of value" which makes no real sense, as it assumes that "someone" is always willing to buy. Why should anyone be motivated to buy Bitcoin, beyond the classic "great fool theory" trap?
