// grab table from dictionary of dfs, clean it up a bit
fuel_ferc1_df = (
_clean_cols(ferc1_raw_dfs["fuel_ferc1"], "f1_fuel").
// Standardize plant_name capitalization and remove leading/trailing
// white space -- necesary b/c plant_name is part of many foreign keys.
pipe(strip_lower, ["plant_name"]).
// Take the messy free-form fuel & fuel_unit fields, and do our best to
// map them to some canonical categories... this is necessarily
// imperfect:
pipe(cleanstrings, ["fuel", "fuel_unit"],
[pc.ferc1_fuel_strings, pc.ferc1_fuel_unit_strings],
unmapped="").
// Fuel cost per kWh is a per-unit value that doesn"t make sense to