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Doctorate in Mechanical Engineering, entreprenuer
Interests: diesel and gasoline engines, cars, aircraft, railroads, electric drives
Recent Activity
a1_vin This is what you really want: I am not sure why this has not been more popular has it combines the best of both worlds and the close fit of the trailers would minimize air drag. The only disadvantage that I know of is that the trailers are somewhat heavier to withstand the buff forces and that eats into the net permissible load on the highway but a lot of loads bulk out anyway.
Much of the freight hauled in the larger tractor trailer rigs is not driven to the end user. It is taken to a terminal where it is sorted for and taken to the customers in smaller trucks. No one is going to drive one of the doubles into a European city. There are exceptions especially for large manufacturing operations. A car manufacturer may make engines in one plant and take it to another plant in a different city for final assembly with the car. But these plants often have rail spurs. At our facility where we manufacture specialized self-propelled ag equipment, we get large tires, diesel engines, seats, steel, etc on a daily basis. All of it comes as less than truckload freight and has been take to a terminal and transloaded onto city delivery trucks.
They are only running double 45 ft trailers. What is the big news? In the western US, we run double 53 ft trailers or triple 27 ft trailers. Anyway, I agree with EP that they should run more of the cargo on trains. We have double stack trains (2 containers stacked one on top of the other) in the US that exceed 12,500 ft in total length. In Europe, most of the railways are electrified but while their passenger trains are first rate, their freight railroad systems is not as well developed or not as well used.
Roger and SJC I think that my desires are the same as yours. Cut down on the use of fossil fuels. The problem is that unless, you truly have excess electric power, making hydrogen from electric power, compressing it, and then converting it back to electricity is probably somewhere in the range of 25 to 40% efficient and even f you used the best possible numbers, 53% which is probably not likely. Hawaii is planning on having total renewable energy in 2045 so there is no excess Solar or Wind energy now nor will there be in the near future. Any, if there was, it would make more sense to put in pumped storage which is about 80% efficient. Basically, I think this smacks of a Toyota "greenwash" stunt. Maybe fuel cells would be useful for military vehicles, drones, or submersibles where stealth is important and there is limited infrastructure for charging batteries. Maybe (and I think that this is a stretch), fuel cells will be used in long distance trucks as Nicola Motors is proposing or in construction and ag machines where relatively constant high levels of power are required. For cars, delivery vehicles, and transit vehicles batteries seem to be much more energy and cost efficient.
Why? There is nowhere to go in Hawaii that could not be driven to with a Tesla or Bolt or even a Leaf. In a Tesla or Bolt, you could easily circumnavigate the big island and still have charge left.
SJC If you are going to quote best case efficiencies for your side of the argument than use it for the other side. GE offers combined cycle efficiencies of 62.22 % to make electricity from natural gas. Real world it is probably 58-60%. Roger Likewise, plus I think that I would take Nikola Motors numbers with a few grains of salt. "Nobody would be so dumb as to use coal-fired or natural gas power plants' electricity in electrolyzer (sic) to make hydrogen" Really! It does not matter anyway as electricity is fungible. Anyway, there is no energy cheap easy source of hydrogen. If you were going to make hydrogen, probably the best technique would to use nuclear power and go with high temperature electrolysis.
SJC If you have bio-methane, a modified diesel engine such as the Cummins Westport "Near Zero NOx" engine would be better than messing with hydrogen. Or, if you insist on making hydrogen, use the hydrogen for direct reduction iron where you would replace coke from coal.
If you run straight electric or battery electric, you will be about 80 to 90% efficient. If you run a fuel cell about the best estimate I have seen for efficiency is 40% but 25% is probably a better number for common current practice. If the usage is not sufficient to make overhead catenary economically practical, a better solution would be to have a battery electric system where the train is charged either at the stations or using short sections of overhead catenary. Last fall, I rode a urban transit rail system in northern Italy that worked on such a system If you are running at 25 to 40% efficient and using coal for electric power, even diesel power is probably cleaner than using coal fired electric power to generate hydrogen. About 44% of German electric production is coal based and about another 6% is burning biomass which could be better or worse than coal.
Jason Burr If you wanted to use wind power for emergency propulsion, I would suggest that sails would be much more efficient. The hull is a trimaran so it should sail reasonably well without a keel.
Why build fuel cell vehicles in South Korea? A modern BEV would take you anywhere in South Korea with range to spare. The place is like an island as you have water on 3 sides and North Korea on the other side. They get about 70% of their electric power from fossil fuels, 20% from nuclear, and about 10% from renewables including hydro. They have no oil and some natural gas but are also importing natural gas. Why are they wasting resources on hydrogen?
This is not a new miracle power source. It take a lot of electrical energy to make aluminum from aluminum ore. So what you are doing is storing the energy in powdered aluminum and the releasing some of it in the form of hydrogen. This is not going tobe an economic power source for most applications but it might be a stable compact source of power for the military.
ep, I agree that there is little or no information on how it works or even what the intended application is. Looking at it, it has lots of gears including a planetary, what appears to be a clutching mechanism and what I assume is a motor generator. Does it have a hi-lo range? Maybe. Is it a lock-in 4 WD or is it AWD?
SJC -- What new FIT EV at a low price? The only information that I can find is that it will still be a lease only compliance car with relatively poor specs.
eci, If you are looking for value, I would expect that the GM Bolt is a better value. The May issue of SAE Automotive Engineering had an interesting commentary on a competitive tear down on a Tesla 3. They said it was 2 different vehicles. The electronics were state-of-the-art but the chassis design was dated.
Maybe slower than Tesla on the first launch but not on the second. I would also guess that the Porsche is better on the race track. Now, how does the NEDC range rating compare with the EPA rating. I wish we had a unified rating that was realistic. I believe that there is a new World rating but I am not sure how that compares with EPA either.
A major advantage of this chemistry would be that it does not use cobalt. Will it be a commercial success? Or maybe it will be surpassed by other better chemistries? Anyway,it looks hopeful.
The current issue of The SAE Automotive Technology magazine has an interesting take on the Model 3 based on inspecting a total tear down of the car. They said it was 2 different cars. The electronics were state of the art but the chassis design was relatively dated compared with most modern cars. Anyway, I hope that they make it but they are struggling to produce 100 K cars a year in a factory that made 400 K cars a year when it was run by Toyota and GM. Also, there was a interesting comment in an article in the NY Times comparing the apparent success of Space X with Tesla. They said that building modern cars was not rocket science, it was really much more difficult.
HarveyD, Those are the claims and I would tend to believe them. These units are also "walk away" safe. They do not need power for pumps, etc. for a safe shut down in the case of an emergency.
Low carbon hydrogen seems to be a real oxymoron as long as you are burning fossil fuel to generate electric power. The wind and solar power could more efficiently be used to displace the electricity being generated by fossil fuels. Unfortunately, Japan closed most of their nuclear power facilities after the tsunami and increased their dependence on coal.
I think that NuScale is close to starting construction of the initial commercial installation with 12 50 MW small modular reactors near Idaho Falls
Nick, The number I have seen is 700 years worth of power at current total power usage from the DU only (I think that this number was from a NOVA PBS program). Not only could we close down all the fossil fuel plants, we could also decommission the ugly wind turbines cluttering our landscape :>)/2 (only half in jest).
In the United States, the electric-vehicle conversion is $69,000 for vehicles with an electric range of 50 miles and $89,000 for vehicles with a range of 100 miles. I did not see a price for the Fuel Cell option but I would guess that it is much, much more. Brian: How about Kilo or Mega Joules per kilometer? Then the units would be completely rational.
I am somewhat disappointed to find out that it is front wheel drive only and not all wheel drive. I live in serious snow country and 4WD or AWD drive is a necessity on some days. I would thaink that it would be easy enough to have an AWD drive option with a second rear motor.
This does not seem to be the best idea ever. Take methane, reform it to hydrogen while generating CO2 (the heat value of the carbon is used to drive the reaction), then spend more energy to compress it and then burn it in a diesel engine. It would be easier and more efficient to just run the methane in the diesel engine. As it is stored at a lower pressure and contains more energy per unit volume, it would be easy to run all day on CNG. Someone is sure to tell me that the hydrogen will be generated using electrolysis from surplus wind turbine energy. However, more than 50% of the UK energy comes from fossil fuels (natural gas and coal) and some of the supposed renewable energy comes from burning imported wood pellets. So if you are using wind turbine energy to provide electricity for electrolysis, it is at the coast of increasing the fossil fuel burn elsewhere.
Our local business area (North Salt Lake, Utah) UPS driver drives about 60 miles a day but he told me that most of the home delivery drivers average around 100 miles per day. If a vehicle could reliably drive about 120 to 150 miles on battery, then there is no need for a fuel cell extender. This obviously not going to work in rural areas of the west. But even if you needed a range extender, I would think that it would be more cost effective to use a CNG fueled ICE especially given that most hydrogen comes from NG reforming.