Not my century, I'm afraid, so I have had to expand the meaning of "favourite" somewhat.

Pelléas et Mélisande
Der Rosenkavalier
Peter Grimes
Madama Butterfly
Palestrina
Il Prigioniero
Francesca da Rimini
Wozzeck
Jenufa
Zazà

Bit late to this but:
Fidelio
Barbiere di Siviglia
Norma
La Traviata
Die Meistersinger von Nürnberg
Faust
Carmen
La Giaconda
Pagliacci
Andrea Chénier

More trolleybus expansion in Lyon, with the opening on 28 Feb of new "TramBus" route TB12 from Gare Part Dieu to Kimmering. The route will next be extended to Sept Chemins. The designation TB as TramBus is intended to signify the BRT nature of the line.
Photo: N.Tresontani

I’m not a civil engineer nor a quantity surveyor, but obviously a full metro involves heavy installations and heavy vehicles. So more substantial construction is part of the extra cost.
Then factor in bigger electric plant, heavy trains and complex signalling systems. They all add a lot of cost.

From what I read at the time of the project.

I agree that the overhead wires themselves would need replacing. The substations and feeders would be reusable, as would the support masts which form at least 50% of the overhead line cost.

Regarding your last para, do you know for sure? Would they not have done some future proofing?

I was just using ball park figures. My critics couldn't believe an elevated heavy metro would cost 4X as much as an elevated trolleybus BRT. They were wrong to assume the metro proposal was elevated but if it had been viaduct, your 2:1 ratio suggests $231m/2=$115m/km, which is 6X the trolleybus BRT

I've just written a short thread on metro construction costs but wasn't able to tag you in, even though I tried. It was a quote reply response to Diego.

2. I didn't say in my first thread that the metro proposal would be on viaduct. It was likely to have been mostly at grade/in cuttings, with an alignment parallel to the eBRT but through less density. The $1.5bn cost for the 18.5km line works out at $81m/km-matching the lowest cost mentioned in 1

1. Heavy rail and metro systems are v. expensive, much more than many seem to think. A recent article from the Transit Costs Project gave a weighted average of $231.21m/km while even the cheapest 100% surface line cost $81m/km.
@denisagar.bsky.social @alonlevy.bsky.social
transitcosts.com/new-data/

4/4 "We don't live in an ideal world. Often, some 'perfect' solutions are unaffordable and decision makers (whether in cities, businesses, or families) have to choose something that is good rather than ideal.

3/4 "A metro extension offers much greater capacity, somewhat higher speed, and greater labour productivity. On the other hand, this was quarter of the price, much quicker to install, and meets demand for the next few years. Ultimately the decision turned on shortage of capital.

2/4 "It is hard to be sure of accurate construction costs but the best I can find is a cost of $355m, equal ~$19m per km for the trolleybus project. In contrast the proposed metro extension was $1.5bn. So the eBRT is less than a quarter of the cost. How should you evaluate the two choices?

Denis is questioning the sense of the elevated trolleybus lines in Mexico City (and suburbs). So here's some information that I posted on "the other site" at the time.
"Inevitably there has been some griping from various pundits, who wanted a metro extension, not an e-BRT.
@alonlevy.bsky.social
1/n

It is a quicker and cheaper build than Skytrain. The electrical installation is compatible with LRT and no doubt it could be upgraded once demand builds up to a suitable level.
I’m not sure that the viaduct is constructed to carry the weight of a metro, which is much heavier than a BRT.

Totally agree. Even with recent improvements, BEBs have much lower productivity than trolleybuses with auxiliary batteries (or diesels). The lay reader of the article may not realise that a 15min layover is *not* normal. Labour is the major opex cost; 15 min breaks at each loop is a huge added cost.

Updating of Bucharest's trolleybus system continues. After receiving 100 Solaris trolleybuses (LH photo) about two years ago, it is now receiving 22 units from Yutong (RH photo). There are plans to call for bids on another 100 buses.

Which of the two models do you prefer?

By the time you become a captain (= a colonel in the army) you have become a gentleman. No doubt there would be some who might whisper meanly but they would usually be the mediocre types. The real gentlemen would accept their brother in arms and admire his rise up the ranks. @alonlevy.bsky.social

Sorry, I haven’t read the cause of your question. Could you give me the background or a link.

Even if came from humble origins, the captain by that time would be firmly in the middle class, edging into the upper-middle class.
Historically the aristocracy and gentry would send sons into the navy. But talented men from poorer backgrounds could rise to the top.

This presentation (on Thursday) on the role of trolleybuses in the electrification of public transport looks interesting. The focus is on the Global South, starting with the modernization and expansion of trolleybus operations in Mexico City.
Registration: lnkd.in/eafVwZW8
@alonlevy.bsky.social

As a rough rule of thumb, trolleybuses with In Motion Charging typically have batteries that are only 10% of the size of battery buses. Think: requires only 50% wiring of routes and ETBs need only 60 to 70kWh batteries. Looks like resource efficiency to me. @gspeng.bsky.social @ofsevit.bsky.social

3/3 At first sight, the private bill procedure sounds onerous but in practice the supposedly deregulated Transport and Works Act process can take a lot longer and be more frustrating than obtaining a private Act of Parliament.

2/3 the previous process was parliamentary one. Proposals for construction of new tramways (and trolleybus lines) were included
in a Private Bill. The proposals were examined and debated by a committee of MPs and, with luck, the proposer obtained a private Act of Parliament for their project.

Thanks for a most interesting article.
One item you mention is the need to obtain an order under the Transport and Works Act for new projects including tramways. This act was introduced decades ago as a supposed deregulation measure but IMO it has been more cumbersome than the previous process1/3

This experiment is a distraction.
As you and @alonlevy.bsky.social say, the UK needs a steady programme for overhead electrification. What we get is a dire mix of stop-go investment, policy adviser proposals for discontinuous wiring using battery/pantograph EMUs, plus wild ideas about hydrogen (!!)

The chart in the tweet above shows the cost per vehicle revenue hour is slightly lower for trolleybus than for diesel buses.

4/4 I wonder if this is mostly a performance by an ambitious young minister seeking attention, and that after a few sacrificial lambs have been slaughtered, wiser counsels will prevail.

3/4 There is at least some comfort in the article, as they do suggest that trolleybuses will be concentrated on trunk routes and they do mention IMC (In Motion Charging).
It's all rather odd, given that Athens is one of the pilot cities for the E-BRT 2030 project, using IMC trolleybuses.

2/4 Cost is not the only factor to consider, agencies need to consider the efficiency and effectiveness of service delivery. Back in the summer as this row brewed up, BEB service was severely impacted by the heat (HVAC causing battery drain), with buses only doing half their daily mileage.