Amazon will add 615 megawatts of solar projects to its existing and announced renewables portfolio of more than 2.9 gigawatts, the technology and shipping giant said on Thursday. The projects will go up across the world — in Australia, China and the United States — to power Amazon’s shipping warehouses and data centers. Amazon did not say who would develop the projects and declined to comment on what companies were involved in the installations. The largest additions will come in the U.S., where Amazon will add two solar installations in Ohio and another in Virginia, totaling 410 megawatts.