About half of the U.S. faces an increased risk of power supply shortages over the next decade, which could lead to blackouts and power conservation measures, the North American Electric Reliability Corporation said Tuesday. As U.S. electricity consumption rises from artificial intelligence data centers and buildings and transportation electrification, efforts to increase power generation fail to materialize, leading to a widening imbalance between supply and demand, the company said in its annual long-term reliability assessment.