Due to the extremely competitive nature of Bitcoin mining, the miners must seek out the cheapest power on the market. By definition, cheap power has low demand,

Due to the extremely competitive nature of Bitcoin mining, the miners must seek out the cheapest power on the market. By definition, cheap power has low demand, so the miners are not crowding out other "higher" uses of the power. In many cases, this power would be otherwise wasted. In some cases, miners are capturing vented or flared waste gasses from other processes (gas wells, landfills). Many miners have power purchase agreements and curtailment arrangements in place with grid operators that perform two very useful functions: - Allow grid operators to better plan for demand, since they can anticipate the large load from the miner. Secondary effect: overbuild generation capacity when building new power plants, since there is a ready buyer for the new power. - Sell energy back to the grid when weather strains capacity. Bitcoin miners can switch off instantly when the grid operator sends a signal, so the grid is more resilient to both predictable (cloudy days) and unpredictable (plant failure) supply changes. So Bitcoin mining is good for power grids, both from the standpoint of capacity and stability.