Wondering about how much electricity demand in the U.S. could be provided by rooftop solar? Then, a new report released by the National Renewable Energy Laboratory (NREL) has the answers.
NREL’s report ‘Rooftop Solar Technical Potential for Low-to-Moderate income (LMI) households in the US’ is mainly focused on the solar photovoltaic (PV) potential on US households along with LMI levels. The levels are defined as those who earn 80% or less of the area median income. Today, the solar power potential is expanding and transcending beyond the demographic of the higher-income households. Initially, rooftop solar PV potential was adopted mainly among higher-income households and the declining costs of solar PV are said to attribute this expansion.
The study utilized a combination of light detection and ranging (LiDAR)-based scans of buildings and statistical techniques in order to assess rooftop solar PV potential. And, the study brought to light that of the 116.9 million residential buildings in the US, 67.2 million buildings were suitable for solar PV. The total generation potential was nearly 75% of residential consumption.
The rooftop solar PV potential is mainly a function of the building and roof orientation. And, in cold climates, the buildings were built to maximize the inward solar radiation. So, counties like Alaska and Montana were found to have a higher percentage of potential LMI rooftops than counties in Arizona.
Meanwhile, the NREL study was said to have been inspired by a US Department of Energy (DOE) Solar Energy Technology Office announcement on the falling cost of solar energy resulting in 971 GW of solar capacity nationwide. This could reportedly provide 33% of electrical generation by 2050. The study by NREL reiterated the technical viability of the 33% among current LMI households. However, the study did not estimate the economic viability. And, to achieve the economic viability, it has been suggested that deployment of newer models should be used. The report also suggested that coordination issues in rental-occupied and multi-family buildings need to be addressed.