The base exclusions consist of two main categories of exclusion – the protected area layer and the techno-economic exclusion layer. The base exclusions form the fundamental exclusion set that the additional criteria of the Core and SB 100 Terrestrial Climate Resilience Study screens are added to. The merged footprints of these primary two layers are modified by the Bureau of Land Management Land Use Plan Amendment (LUPA) development focus areas (DFAs) and variance process lands, and the general public lands in the DRECP. These areas allow for renewable energy applications and are therefore exempt (erased) from the base exclusions layer, even if the protected area layer or techno-economic exclusion layer identified the area as an exclusion. The DFAs are partitioned by technology type so that only the DFAs that allow solar energy are applied in this modification.   

The area of California remaining after removing the base exclusions is called the resource potential basemap. It forms the starting point (or base) used in renewable resource estimation and defines where environmental and land-use datasets can be applied in exploring implications. 

More information about this layer and its use in electric system planning is available in the Land Use Screens Staff Report in the CEC Energy Planning Library.