Right but what I'm getting at is that there can be tradeoffs that might make designing for maintainability mean optimizing for something less important to the end user.
Do you optimize an engine for how easy it is to replace a filter once or twice a year (most likely done by someone the average car-owner is already paying to change their oil for them), or do you optimize it for getting better gas mileage over every single mile the car is driven?
We're talking about a hypothetical car and neither of us (I assume) design engines like this, I'm just trying to illustrate a point about tradeoffs existing. To your own point of efficiency being a trade with durability, that's not in a vacuum. If a part is in a different location with a different loading environment, it can be more/less durable (material changes leading to efficiency differences), more/less likely to break (maybe you service the hard-to-service part half as often when it's in a harder to service spot), etc.
Only TCO matters, that is the efficiency you actually optimize for, ie dollar per mile[1]not miles per gallon.
If the car is going to need to be in shop for days needing you to have a replacement rental because the model is difficult to service and the cost of service itself is not cheap , that can easily outweigh any marginal mpg gain .
Similarly because it is expensive and time consuming you may likely skip service schedules , the engine will then have a reduced life, or seizes up on the road and you need an expensive tow and rebuild etc .
You are implicitly assuming none of these will change if the maintenance is more difficult , that is not the case though
This is what OP is implying when he says a part with regular maintenance schedule to be easily accessible.
[1] of which fuel is only one part , substantial yes but not the only one
I'm just gonna copy and paste a response to another similar comment:
The point that I am making (obviously, I think) is that tradeoffs exist, even if you don't think the right decision was made, your full view into the trade space is likely incomplete, or prioritizes something different than the engineers.
Putting some random number of hypothetical mpg improvement was clearly a mistake, but I assumed people here would be able to get the point I was trying to make, instead of getting riled up about the relationship (or lack thereof) of oil filters and fuel efficiency.
I did read that before commenting, to be clear - the specific nature of your proposed optimization is not important and I took your premise to be true ie it will improve fuel efficiency and therefore save some money.
—
In general, the point was it is not operational efficiency in ideal conditions alone and serviceability is an important component because it can add to the overall cost of ownership significantly and individual car owners (in comparison to fleet) are typically poorer in factoring this in their buy decisions.
——
It comes down to numbers , if the proposed change, results in 10% improvement probably not worth it, 10x then definitely so .
I.e will the car become 22 MPGe or 200MPGe . Larger the gain more trade-offs like serviceability or life expectancy all can be sacrificed.
hybrids costs more upfront (both sets of expensive components - transmission/motor +engine/battery) but still work if driven enough miles, as the gain in efficiency makes up for the upfront.
Exact number of that miles is localized to you and me - depends things like tax difference including tolls, gas prices, MPGe diff, electricity prices, interest and purchasing power of currency other consumables costs like tires and so on.
Yes propaganda and bullshit, but by way of exaggeration and puffery, not lying.
I wouldn't expect even a lightly informed mid-wit to think that this murderbot held the ground by itself; and I don't think the author expects that either. Thus something else is probably going on. To wit - puffery.
The murderbot is remotely operated, so it did not held the ground by itself, though it is claimed that it might be able to do some things autonomously.
I wrote a simple tool, when I was a kid, that dumped binaries into VGA mode 0x13 and allowed me to vary the width. Mode 0x13 is one byte per pixel so it was just a simple REP MOVSB to put data into the buffer (no worrying about bitplanes). It was so useful in reverse engineering software. Besides raster data, regular data structures often jump out.
One gram of finished 3nm packaged semiconductor is roughly equivalent to half a kilogram of refined aluminum in terms of energy cost. If you want to spend a lot of energy for not much mass, photolithography is fantastic.
"Maintenance costs of the lines may be increased by electrification, but many systems claim lower costs due to reduced wear-and-tear on the track from lighter rolling stock. There are some additional maintenance costs associated with the electrical equipment around the track, such as power sub-stations and the catenary wire itself, but, if there is sufficient traffic, the reduced track and especially the lower engine maintenance and running costs exceed the costs of this maintenance significantly."
We once dammed basically every river in the nation because it was in vogue at the time.
Maybe building overhead power lines for rail infrastructure should be the "hip" thing right now instead of AI. Maybe building oodles of solar power farms and batteries should be "hip"
We built electrical infrastructure to the most remote residences just because we could and because it was an investment in our people. We directly funded our massive and formerly world class rail network because we could, and because it would pay off. We built a world class road network half as a make-work project, and it still pays dividends. We purchased Alaska, with no obvious reason. We built a space program to have slightly better nuclear weapons, and it's part of the reason we were so dominant in computer chips for so long.
We have spent something like 40 trillion dollars over the past 25 years, and almost none of it on anything of real value. More than a little of that debt is just handouts to already rich people.
We can build new electric transmission lines and I'm so tired of things that we absolutely 100% can do if we just demand it be done being somehow treated as a problem. America can afford infrastructure.
> Would this be less efficient than battery powered EVs?
Measured in terms of mass * distance, trains with steel wheels will beat anything with rubber pneumatic tires.
Part of the magic of hybrid trains is that you can have multiple generation units that can be turned on or off as needed.
---
Efficiency is just one consideration for a power plant.
Historically, reliability has been more important than efficiency, especially for industrial applications like locomotives. In other words, locomotives are probably not as efficient as they could be. For instance, you could use a lower viscosity engine oil for lubrication, but that would reduce reliability as engines fail due to friction.
For any particular person, you can tell a story that satisfies "Why?". But for a large number of people, you have to answer "Why?" for one sub-group at a time.
In other words, there's not a single answer that will answer this in a satisfying way.
To answer a different question: It appears that the Israeli government and military wanted to bomb Iran again, and the United States executive branch and military decided to help out. This is an incomplete and unsatisfying answer. Sorry.
> In other words, there's not a single answer that will answer this in a satisfying way.
There could be one, but it would be a book-sized answer (and probably a Tolkien one, if not more).
Every conflict is multi-faceted and happened for a variety of reason, some mattering more than other. Any conflict involving the middle east and you have to go back almost 80-years of history to really provide a satisfying answer. Control of world oil supply, trades with China, opportunistic war to appease local voter pool, diversion from problematic affairs, diplomacy with Israel (which as it own thousand fold reasons for this war), Iran being left weak after losing most of their local allied militia, internal uprising due to a economical crisis caused in part to the removal of the agreement on nuclear and the trade ban that followed ... They all probably play a part.
Most maintainability conflicts come from packaging and design for assembly.
Efficiency more often comes into conflict with durability, and sometimes safety.
reply