ERWH sizing doesn't hit all capacities

We have some code for autosizing (based on guidance in the BA HSP, originally from HUD, see Table 8). Code is here. The autosizing is based on the number of bedrooms AND number of bathrooms, this is one of the very few things affected by # of bathrooms. We are using an "auto" option for the number of bathrooms (here). With our current bedroom>bathroom relationship, we never hit a 4.5 kW element size in our sampling results (see figure below). Since this is a pretty common WH element capacity, it seems like we ought to have them in the stock? I doubt this has much impact on annual energy consumption, but it would matter in terms of peak demand (in a single building). In aggregate the peak demand impact probably washes out.

One proposed solution would be rather than deterministically assigning the # of bathrooms based on # of bedrooms we come up with yet another tsv for this relationship to add some variability. I'd imagine that data wouldn't be too hard to track down?

NREL / resstock

ERWH sizing doesn't hit all capacities #1037