Rooftop Solar Panels Can Meet 40 Percent of US Electricity Demand

Analysts from the Energy Department's National Renewable Energy Laboratory (NREL) reveal the potential use of the rooftop photovoltaic (PV) systems across the nation. These rooftop solar panels can provide 1,432 terawatt-hour (TWH) and 1,118 gigawatts (GW) of capacity that is about 39 percent of the U.S. electricity sales.

Science Daily reports that the analysts come up with the estimates using LiDAR, otherwise known as light detection and ranging data, the PV-generation modelling and the Geographic Information System methods. The PV-generation modelling computes the durability of rooftops that can host PVs in 128 cities nationwide. This makes up approximately 23 percent of U.S. buildings and can meet PV-generation results for 47 of the cities. 

"This report is the culmination of a three-year research effort and represents a significant advancement in our understanding of the potential for rooftop PV to contribute to meeting U.S. electricity demand," explained Robert Margolis, the NREL senior energy analyst and co-author of the report.

The cities that are seen to have high solar energy potential estimates include San Antonio, Texas (51 percent), Syracuse, New York (57 percent) and Concord, New Hampshire (72 percent), according to Co-Exist. On the other hand, Washington can only get 16 percent from solar panels and New York City only 18 percent.  Margolis said that PV in urban places could surpass the estimates if the systems are installed on canopies in open spaces that include the parking lots. It can also be integrated onto the facades of the building.

A rooftop photovoltaic power station, also referred to as rooftop PV system, are solar panels that generate electricity mounted on the rooftop of the edifice, commercial buildings or residential. Typically, the rooftop PV system of a residential building can generate about 5 to 20 kilowatts (kW). On the other hand, PV system in commercial buildings can have as much as 1000 kilowatts or more.