Do mappings already exist for figuring out which balancing authority a city belongs to?

Hi folks.

I found out last week that the EIA appears to publish hourly historical CO2 intensity figures for electricity consumption for every balancing authority in the United States, with a lag of only a few days under what I think is a pretty open data license:

If I have a series of city locations, how can I work out the underlying balancing authority it is using?

What I’m trying to do now is go from a city name, like Detroit in Michigan, and from there, figure out that the underlying balancing authority is say… MISO.

A bit more about what I’m doing and where I am so far

Here’s the data - if you download the spreadsheet, you’ll see aaaalll the way on the right a column listing the carbon intensity of consumption, which includes imported energy:

I’ve now written some code that fetches these spreadsheets, pulls the necessary timestamp, BA and carbon intensity figures, then puts them into an sqlite database, as well as handy compressed parquet file

I know things like this exist, which provide shapefiles for all the control areas / balancing authorities in the states:

Does a mapping service already exist so that if you have a given city, you can return the balancing authority, and therefore the likely carbon intensity of the electricity consumption?

I’m asking because it would be nice to figure out how to not build this if possbile, and it doesn’t seem a totally weird request, that maybe an electricity modeller has had to do themselves before.

A side note about the data being open:

Here’s what I’m basing the “data is open” comment about:

Public domain and use of EIA content

U.S. government publications are in the public domain and are not subject to copyright protection. You may use and/or distribute any of our data, files, databases, reports, graphs, charts, and other information products that are on our website or that you receive through our email distribution service. However, if you use or reproduce any of our information products, you should use an acknowledgment, which includes the publication date, such as: “Source: U.S. Energy Information Administration (Oct 2008).”

Source: U.S. Energy Information Administration - EIA - Independent Statistics and Analysis