Introduction
The Indianapolis City-County Council will soon consider the 2025 Indianapolis Public Transportation Corporation (“IndyGo”) budget. So this may be an appropriate time to review some facts that if past is prologue IndyGo won’t divulge to the Council. Specifically:
IndyGo isn’t green; replacing all IndyGo bus trips with car trips would reduce the city’s carbon footprint.
IndyGo’s Red Line bus-rapid-transit (“BRT”) route hasn’t provided the increased reliability that IndyGo claims.
That route isn’t particularly “rapid,” either.
Even just the local-tax portion of IndyGo’s subsidy will exceed what replacing all its bus rides with cab rides would cost.
The proposed budget could probably buy four times as much transportation by cab as IndyGo will provide by bus.
IndyGo Isn’t Green
We base the assertion that IndyGo isn’t green on the January 2024 IndyGo board report, which said that IndyGo used 1,166,476 gallons of diesel fuel last year. If burning a gallon of diesel fuel emits 22.45 pounds of carbon dioxide, IndyGo’s diesel-fuel use emitted about 26.2 million pounds of carbon dioxide. That same report also said that IndyGo had given 6,730,357 bus rides. If the 2022 ratio of FTA reported IndyGo passenger-miles to IndyGo trips is any indication, that many rides in 2023 translates to about 29.6 million passenger-miles of IndyGo bus transportation.
So IndyGo emitted about (26.2 million pounds of carbon dioxide ÷ 29.6 million passenger-miles ≈) 0.88 pound of carbon dioxide per passenger-mile. In contrast, the 19.37 pounds that gasoline combustion emits per gallon implies that a 24-mpg car emits only 0.65 pound per passenger-mile if it averages 1.25 occupants. And that’s without taking into account the fact that gasoline is often diluted with ethanol. If we had taken that fact into account our emissions estimate would probably have been more like 0.59 pound per passenger-mile.
Now, we hasten to add that IndyGo is likely to become (temporarily) greener next year Its diesel-powered Route 39 will be replaced in October by the electric-powered Purple Line, and it may enjoy a modest ridership increase. Reducing the diesel-powered percentage of IndyGo vehicle miles from 91% to 81% and increasing ridership by 10% would reduce emissions per passenger-mile to about 0.71 pound. But that’s still greater than car emissions.
Moreover, that estimate doesn’t take into account that IndyGo is in the process of an expansion in which the diesel-powered percentage is slated to rise again. A planned third BRT route, the Blue Line, won’t be electric-powered, and the plan is for total revenue miles to increase by another 55%1 by the time the expansion is complete. So the diesel-powered percentage will probably rise back to something like 88%. As we explained elsewhere, moreover, we have no reason to believe that ridership will rise in proportion to revenue miles. If it doesn’t, the buses will become even emptier and thereby increase IndyGo emissions per passenger-mile, probably to more than 2023’s 0.88 pound.
Bus Charging
And our 0.88-pound-per-passenger-mile estimate included only diesel-fuel emissions, whereas emissions additionally result from charging IndyGo's electric buses. Since IndyGo withholds charging data, we don’t know those emissions’ volume. But in a manner we’ll now describe we estimate that the power company emits 2.1 million pounds of carbon-dioxide to charge IndyGo buses.
We start by assuming that IndyGo’s electric buses consume 2.5 kilowatt-hours of electricity per mile (“kWh/mi”), which may be conservative. Range tests reportedly averaged 206 miles, and one source says that battery capacity is 578 kWh, so our 2.5 kWh/mi assumption implies only an 89% average discharge in the range tests.
According to the FTA, the Red Line racked up 684,796 “revenue miles” last year. Although Red Line buses probably traveled farther than that, we’ll multiply that distance by our 2.5 kWh/mi assumption to estimate 1.7 million kWh as the electricity total.
Next we adopt the 10,339 BTU value that the footnote to Table B.6 of the Oak Ridge National Laboratories’ Transportation Energy Data Book gives as the amount of combustion required to deliver a kilowatt-hour to the socket after losses in generation, transmission, and distribution are taken into account. Based on that combustion rate as well as AES Indiana’s projected 2023 fuel mix and the Energy Information Administration estimates for those fuels’ emissions, 1.2 pounds is our estimate of how much carbon dioxide the power company emits to provide IndyGo’s bus chargers a kilowatt-hour of electricity. Multiplying that rate by the 1.7 million kilowatt-hours we estimated for bus charging gives us 2.1 million pounds of carbon-dioxide emissions.
Adding 2.1 million pounds to the 26.2 million pounds from diesel combustion increases IndyGo emissions from 0.88 to 0.95 pound per passenger-mile. And that’s without taking charging losses into account.
What about the Red Line Alone?
Now, this 0.95-pound-per-passenger-mile value is the result for the IndyGo system as a whole. What if we ignore the diesel buses and concentrate on the all-electric Red Line only? Then the emissions would indeed be less than a 24-mpg car’s—but probably more than a 40-mpg hybrid’s.
Specifically, a 40-mpg hybrid with the 1.25-person occupancy we’ve been assuming emits only 0.39 pound of carbon dioxide per passenger-mile, or maybe more like 0.36 if we take ethanol dilution into account. And Red Line trips tend to be relatively short: 3.6 miles instead of the system-wide 4.4. This implies that the 1,168,599 Red Line trips taken during the twelve-month period that ended in June 2024 provided 4,229,611 passenger-miles. Dividing that into the 2.1 million pounds of carbon dioxide implied by the same period’s 686,686 Red Line “revenue miles” yields 0.49 pound of carbon-dioxide emissions per passenger-mile: more than the 0.39 that a 40-mpg hybrid emits.
And How about Those Solar Arrays?
Of course, IndyGo likes to tout its solar arrays when bus charging comes up. And its solar-array use may indeed reduce Red Line emissions below what the plot above indicates. On the other hand, our Red Line calculation was based only on “revenue miles,” i.e., only on the miles traveled while the bus is actually accepting passengers, and it appears that Red Line buses additionally travel a lot of non-revenue miles.
As “About IndyGo’s Solar Array” explained, moreover, the solar arrays are a red herring when it comes to electric buses, except to the extent that they actually power the bus chargers and do so directly rather than through the grid. Although IndyGo has been cagey about bus charging, it seems likely that IndyGo buses are mostly charged from the grid, so to a great extent IndyGo’s solar panels are probably irrelevant.
Anyway, we saw above that IndyGo would emit more than cars do even if charging buses caused no emissions at all. So shuttering IndyGo would reduce the Indianapolis carbon footprint even if all erstwhile riders went by car or cab. And an on-board survey suggests that only about half of them would.
“Increased Reliability”?
Since BRTs enjoy dedicated lanes, it might seem reasonable that they’d afford the increased reliability that IndyGo claims for them. But IndyGo’s August 2024 board report showed that even after five years of operation their on-time performance hasn’t consistently exceeded that of the system as a whole. Recently, in fact, it’s been decidedly worse:
Not So “Rapid”
Well, those dedicated lanes should at least give the BRT buses a speed advantage, one might think. After all, they’re called “bus rapid transit.” If we divide IndyGo’s “vehicle revenue miles” by its “vehicle revenue hours” in the FTA reports, though, we find that IndyGo’s BRT buses are no faster; over the last five years, in fact, they’ve averaged only 13.4 mph while its other buses have averaged 13.7 mph. And when we check further FTA data we find that BRTs tend not to be very fast in other cities, either.
Local Subsidy Alone Exceeds Cab-Transportation Cost
In November 2016, after much government-funded advocacy, an Indianapolis referendum approved a transit income tax to fund IndyGo’s current expansion. In that year IndyGo would end up providing 42,892,469 passenger-miles of transportation, and the local-tax portion of its subsidy was $39,000,284. In 2023 dollars that’s about $49 million, which works out to $1.13 per passenger-mile.
But in 2018 transit-tax collection began, and by 2023 the annual local-tax subsidy had increased to $117,771,678. Yet despite the massive funding increase IndyGo actually provided less transportation in 2023 than it had in 2016. We don’t have an exact figure for 2023 IndyGo transportation, but it was about 31.4 million passenger-miles if 2023’s ratio of IndyGo’s passenger-miles to its bus rides was similar to 2016’s. This would make 2023’s local-tax portion of the IndyGo subsidy $3.75 per passenger mile; in all probability that metric had more than tripled.
This means that the local-tax subsidy alone exceeded even what taking cabs would have cost. Let’s say cab fare consists of $2 per mile on top of a $3 pick-up charge. With tip a cab ride whose length is the 4.4-mile IndyGo average will cost $14.16. If cabs were never shared this would come to $3.22 per passenger-mile: less than the local-tax portion of the IndyGo subsidy.
And cabs are indeed shared. Since we don’t know how often, let’s just assume that most cab rides are not shared but that, say, 22%, 6%, and 2% of them are respectively shared by 2, 3, and 4 passengers. If we throw in a $0.65 charge per extra passenger, cab transportation under those assumptions averages $2.35 per passenger-mile.
So shuttering IndyGo would not only reduce Indianapolis’s carbon footprint but for the populace as a whole would also save tens of millions of dollars even if all those bus rides were replaced by cab rides. And an on-board survey suggests that more than three-quarters of them would not be.
The Proposed 2025 Budget
Moreover, considering only the local-subsidy portion of the subsidy understates the full expense. To get a fuller picture we’ll now consider all the expenditures in IndyGo’s proposed budget for 2025. And we’ll want to express expenditures on a per-passenger-mile basis, so we’ll first make a rough projection of how much transportation IndyGo will provide next year.
If IndyGo’s “passenger service” projection is any indication, IndyGo expects to provide only 2.5% more transportation in 2025 than it did in 2023. However, at least the fixed-route component of IndyGo’s 2024 ridership is on track to exceed its 2023 ridership by 3.3%, so we’ll project a greater transportation increase than that; let’s (somewhat arbitrarily) say that 2025 transportation will be 10% greater than the 2023 value. This puts our 2025 transportation estimate at 34.5 million passenger-miles.
Now, IndyGo presented its operating budget as being $146.8 million. Our guess is that it arrived at this figure by omitting depreciation and amortization, which might have added something like $35 million. But the $4.25 per passenger-mile we get by nonetheless sticking with the presentation figure and dividing it by our transportation estimate still greatly exceeds the cost of cab transportation. Although that’s the figure the plot below uses, a more-inclusive definition of operating expense would probably have resulted in a cost estimate at least double the cost of cab transportation.
If we instead ignore the accounting cubbyholes and divide IndyGo’s entire $342.2 million proposed budget by our transportation estimate, we obtain the $9.91-per-passenger-mile value represented by the above plot’s rightmost bar. For what IndyGo proposes to spend in 2025, that is, we could probably obtain more than four times as much transportation by cab rides as Indy will provide by bus or van.
True, the rightmost bar overstates IndyGo transportation’s long-term cost; a significant fraction of that total-budget number will be one-time expenditures, some of which have only a remote connection to IndyGo transportation. On the other hand, the $4.25 per passenger-mile represented by the operating-expense bar to its immediate left probably understates it. Again, that quantity probably omits depreciation and amortization. Moreover, the remaining expansion will bring further expense increases that are unlikely to be accompanied by proportionate increases in the transportation that IndyGo provides.
Nearly Half a Billion in Transit Tax and Counting
Finally, we’ll touch on something that should be kept in mind when subsidy proponents bring up the federal funds that the expansion is attracting. Yes, those funds are significant. Amounts such as $75 million for the Red Line, $81 million for the Purple Line, and $150 million for the Blue Line have been reported, so the expansion will presumably have attracted well over $300 million by the time it’s completed.
That’s a large amount, but the transit income tax that the expanded system requires is also large. IndyGo’s presentation lists the transit-tax amount as $48.9 million, but that’s only the portion earmarked by IndyGo accountants for operating expenses. The amount of transit tax residents actually have to pay in 2025—and remember that this is in addition to the portions of their local property, state sales, and federal gasoline tax that IndyGo also receives—will be more like $75 million. By the end of 2025 residents will have been paying the transit tax for eight years. So they’ll have paid on the order of half a billion dollars, with no end in sight.
Although we can’t confidently tease the numbers out of IndyGo’s reports, it appears that the transit tax increased the subsidy’s local-tax portion by more than 130%. Yet the amount of transportation IndyGo has provided has actually fallen. True, IndyGo has put a few more buses on the streets and has promised still more. But those added buses haven’t attracted much additional ridership. So although putting more buses on the streets may have made some bus-stop waits a little shorter its effect so far has largely been to make the buses emptier and thereby make the system less efficient.
Perhaps the expansion’s most visible aspect is those fancy new BRT stations. And they are nice. But are they worth the cost? Their arrival-time displays and level boarding are improvements, for example, but how significant are they really in light of the myStop service and the fact that IndyGo’s other buses were already equipped with lifts? And then there’s the off-board fare payment. Since it hasn’t ended up providing any noticeable speed or reliability benefits, it may actually be a net detriment rather than an improvement; it necessitates fare inspectors, which IndyGo had never previously needed.
In short, the value the expansion will add is limited, but its expense is great.
Conclusion
Of course, different people would weigh those costs and benefits differently. But to do so intelligently they should have facts such as those above. And nothing in our experience with IndyGo suggests that it will provide such facts in its presentations to the Council.
UPDATE September 12, 2024: Because of a typographical error, that percentage was originally given as 35% instead of the correct, 55% value.