That's not a remotely conservative assumption, it's a massively generous one. Commercial organizations and personal households pay VERY differently for electricity. For one, businesses that have very high peak power draw, such as 3100kW from a single TR train at peak load never mind the total draw from all 4 subway lines and the many streetcar lines, pay both for amount of electricity used, and for how fast they use it, i.e. when they exceed certain thresholds of power draw their price goes higher and higher. I guarantee the TTC pays a whole lot more than $0.13/kWh for the subway and streetcar networks' electricity even during off-peak, never mind peak.
I would think that since they buy in bulk, are considered an essential service, are a governmnet agency, and use their own distribution systems (they still have to tap into main lines, but don't have to deal with residential cables), that prices would actually be lower that $0.13/kWh, even during peak times. Also, peak period rates are only apply between 7-11, and 17:00-19:00. That's 6 hours out of the 19 hour day for the TTC. Business rates according to Toronto Hydro, are the exact same as residential rates. The number of watts they use within a short timeframe, there's a potential argument there. However, it really only applies to peak periods and even with that I can find no information on extra costs assoicated with such usage. I used that high 0.13 cost for all electricity used by thte TTC. However, let's increase it to $0.20 per kWh during peak times, we find the following cost usages per subway line:
Lines 1 and 2 have much less money available per station because transfers were not included (as was with sheppard before; there are 300,000 transfers between those two lines, however, of those transferring, people tend to use the Line 2 for more stations and to cover more distance than Line 1. In actuality, they actually only have about $4,700-8000 per station to pay for mantainance and the running of stations. Line 1 makes the most per station and Line 4 the least, however, line 4 is the newest and least used, therefore mantainance and cleaning costs are much less. Escalators can even be slowed or turned off during midday to save money. On line 1, mantainance costs for the tunnels are huge, so this increased value will likely pay for quite a bit of mantainance (Assuming a station/small tunnel section is always under construction. You'd have to pay 5 construction workers for 8 hours of work, so 1,200$ (include overnight costs and it increases to about 1,600, but that's including capital costs like signal uprades). Assuming construction materials are another 1000-2000 dollars per day (So about a million dollars a year in upkeep costs per station. It's probably more, but even then, we've barely scratched the budget per station).