Yes, there's no easy way to get "max production" value through API, at least as far as I know.
Best thing mod can do is to find all known power-producing entities on the map and check id of electric grid they're connected to, then get or use hardcoded power production value (iirc didn't see one in prototypes) and multiply by connected entities count.
There's a lot of caveats with this approach:
- What if some of these steam engines aren't actually connected by pipes?
- What if number of boilers/exchangers connected to them isn't sufficient and they can't ever reach their max value?
- What if water is pumped from far-away place and/or various pipe systems have bottlenecks?
- What if belt isn't designed to carry enough fuel to power them all?
- In case of exchanges/turbines, power limited by reactor count and heat-pipe lengths.
- Solar panels don't give constant output, and don't think API has potential production value for them.
- What happens when you add power switches and various production/grid toggles like that?
Etc etc - point is, not really an accurate value, and a hassle to get right that way.
Don't know if game itself takes all of these into account for "production" value in stats when you click on power poles.
So given how easy it seem to be to count these things (as mentioned in the mod description - go to map, Ctrl+C over them, shows count), account for various quirks you built into your grid (switches, ratios, fuel, etc) and set your divider manually (or via another constant combinator, where you just set count), seem to be more trouble than it's worth to maintain such complex and error-prone logic in the mod.
