Consider the following:1.Battery storage2.Biomass generators3.Fuel cells4.Rooftop solar photovoltaic unitsHow many of the above are considered "Distributed Energy Resources"

1. A

   Only one

   Only one. All four are DERs.

2. B

   Only two

   Only two. Under-counts.

3. C

   Only three

   Only three. Rooftop solar, batteries, fuel cells and biomass gensets are all distributed.

4. D

   All four

   All four. Behind-the-meter / grid-edge resources.

Summary. Official key is (d) all four. Distributed Energy Resources sit at or near the load: rooftop PV, battery storage, fuel cells and small biomass generators. None of the four is a centralised utility-scale-only category in this listing.