Wholesale electricity costs, which include the cost of generation plus incremental transmission investments, are about 10% lower in 2035 with a 90% clean grid than they are today, mainly owing to significantly decreased battery and renewable energy costs. Building adequate transmission infrastructure would require relatively modest investment mainly in transmission spurs connecting renewable generation to long-distance transmission lines or load centers. Relying on natural gas for only 10% of generation avoids large investments for infrequently used capacity, helping to avoid major new stranded-asset costs. Keeping some natural gas generation averts the need to build excess renewable energy and long-duration storage capacity – helping achieve 90% clean electricity while keeping costs down.
