Costs of Upgrading Electric Distribution Grids to Integrate Increasing Solar PV Penetrations

The nation surpassed 1 million distributed PV systems in 2016 - installed primarily on the rooftops of residential and commercial buildings - and rapid growth has continued. At the end of 2017, 16.2 giga watts (GW) of distributed PV was installed in the United States. Although distributed PV still provides a small fraction of the total U.S. electricity supply, its contribution to some utility systems has become large very quickly - highlighting the increasing need to develop strategies that maximize PV's benefits to distribution grids while minimizing grid-integration costs.