The shortage threatens the pace of the U.S. transition away from fossil fuels as the Biden administration seeks to decarbonize the grid by 2035.. U.S. renewable energy developers have delayed or scrapped several big battery projects meant to store electrical power on the grid in recent months, scuttling plans to replace fossil fuels with wind and solar energy. At least a dozen storage projects meant to support growing renewable energy supplies have been postponed, canceled or renegotiated as labor and transport bottlenecks, soaring minerals prices, and competition from the electric vehicle industry crimp supply. .... Storing power is considered vital...