Bitcoin has unsustainable demands for energy used in computing especially mining for new bitcoins. All the growth in renewable energy cannot match the demand growth of bitcoin computing.
"In just a few months from now, at bitcoin’s current growth rate, the electricity demanded by the cryptocurrency network will start to outstrip what’s available, requiring new energy-generating plants. And with the climate conscious racing to replace fossil fuel-base plants with renewable energy sources, new stress on the grid means more facilities using dirty technologies. By July 2019, the bitcoin network will require more electricity than the entire United States currently uses. By February 2020, it will use as much electricity as the entire world does today."
