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Doctorate in Mechanical Engineering, entreprenuer
Interests: diesel and gasoline engines, cars, aircraft, railroads, electric drives
Recent Activity
I think that this is the correct way to drive most of the time. The problem is that some drivers may forget to use the brake pedal in an emergency. With a front drive only electric vehicle, at best you would get only max braking from the front wheels. What is the range for the new Leaf?
Peter_XX The electric alternators/motors probably have something around a 90% efficiency (might be a bit better) and there is also a loss associated with the required electronic drives so there is loss that occurs with each pass thru an alternator and motor. However there is also about a 2% loss thru each gear mesh assuming high quality gears and lubrication (a good assumption in this case). I counted 6 gear meshes so that is about 88% efficient from the turbine to the flywheel. Now we need to worry about turbine efficiency. In Volvo's design, the turbine is geared directly to the flywheel so the turbine speed is dictated by the engine speed. In my proposed design the turbine is allowed to run where it develops the most power. My design also allows direct engine braking with the energy being returned to a battery for later use. Now you can enlighten me as to why I am wrong. Also, I did work on an experimental opposed piston diesel about 15 years ago that was designed to have an electrically split turbo charger but I was not the thermal dynamics expert.
Mechanically interesting but also relatively complicated. If I was given the job to design something like this, I think that I would try to build an electrically separated turbo charger with the turbine driving an alternator and a motor driven compressor, a relatively small battery pack and a motor connected to the drive train. That way the compressor could driven for better power response and the turbine could absorb more power under normal driving conditions with excess power being diverted to the power train. This would also support using the power train motor/alternator in a hybrid mode during braking or going downhill.
I could understand working on fuel cells for intercity buses or long distance trucks. However, they do not make much sense for stop and go shorter distance transit buses as some of the currently available battery electric buses are already cheaper to own than diesel buses considering capital cost, maintenance, and fuel/electricity costs and are available with enough battery capacity to run all day without recharging. In Europe, most cities are connected with hgih speed trains so Fuel Cell buses might not make much sense for intercity use. Also, freight could also go by electrified railways.
JMartin Adding hydraulics would just waste energy as the electric drive train is already putting energy back into the battery on deceleration and electric motors are considerably more efficient than hydraulic pumps and motors.
Made in China competitive FC buses will be available by the end of this year. Competitive with what? Chinese made diesel buses? I doubt that. Do you have some verifiable evidence to back up you statement? I doubt that Fuel Cell transit buses will be competitive with battery electric buses anytime in the near future and maybe never as Proterra already has battery electric transit buses that are lower cost than diesel buses to operate considering capital and operating (maintenance and fuel/electricity) costs. A neighboring town, Park City, Utah just bought Proterra buses to replace their diesel transit buses. Maybe Fuel Cells will find a use for intercity buses and long haul trucks but they still have a number of obstacles to overcome.
OK. How many are they projecting to sell in the US?
Nuclear power is carbon free. While it is not renewable, the traveling wave reactors will burn existing waste including depleted uranium and waste from light water reactors. Some one figured out that we can produce enough power for the US for 700 years from the existing depleted uranium stock.
HarveyD: I think that E-P's list referred to nuclear power paranoia. Most counties are not going to be carbon free without using nuclear power.
Wait until Trump finds out that these projects make use of scientific research. He will kill them all:)
B2V might have helped me about 5 1/2 years ago. Driving home after work and after dark, I had a 19-year old driver in a AAA service truck pull a U-turn in my face on a 2-lane road. Not a very fair contest as I had a light weight dual sport motorcycle. I was dressed for the occasion with full face race helmet, padded jacket, padded gloves, heavy pants, and boots but I still ended up with a broken neck, broken back, broken hip, and a very serious cut on my ankle. Spent 3 weeks in the hospital. Also broke the lower front on the helmet but only suffered a black eye, bloody nose and cut lip on my face but I did get a good concussion. Had to wear a "halo" for 3 months and still have some residual stiffness but mostly recovered. Do not know how the driver had not noticed my obnoxiously bright headlight but he was probably playing with a GPS or phone. ai vin: a few years before, I actually rode my motorcycle over a deer -- whump, whump. It was before dawn and the car in front of me suddenly swerved to miss the deer and I did not have time to swerve. Fortunately, the deer was already down and I had adequate clearance and wheel travel.
Mini, factory built, transportable/movable, safe NPPs may be a possibility by 2040/2050? More likely by 2020/2025 NuScale Power, LLC announced today (March 15, 2017) they received notification that NuScale’s first-ever Small Modular Reactor (SMR) Design Certification Application (DCA) was accepted for review by the U.S. Nuclear Regulatory Commission (NRC). The first commercial NuScale power plant is planned for construction on the site of the Idaho National Laboratory for the Utah Associated Municipal Power Systems (UAMPS) and operated by experienced operator Energy Northwest. This first system (which I believe is for 12 units) is already sold and will be placed where there are no NIMBYs to complain. Also note that these systems are "walk away" safe. Conservative estimates predict approximately 55-75 GW of electricity will come from operating SMRs around the world by 2035, the equivalent of more than 1,000 NuScale Power Modules. For more info see
How soon can this process by mass reproduced together with FCEVs of all sizes? Just as soon as it makes sense economically. Fuel cells are getting better but they have been under development since 1838 (no that is not a typo). There are places where they make sense now. Spacecraft, maybe non-nuclear submarines, maybe drones, etc. As a fuel, hydrogen has a lot of problems. All this research did is make the production a very small amount more efficient. You still need to use the energy to split the water which is more than you will get back and need to either compress it or even more difficult, liquefy it. This is more energy gone. Do we have excess renewable energy? Where? For the most part cars, delivery trucks, and transit buses can run more economically on batteries. Maybe by the time fuel cells are ready for prime time, some one will have figured out how to make rechargeable lithium air batteries which will largely negate the need for fuel cells.
HarveyD: Gates and company are working on what is called a traveling wave reactor which will burn existing nuclear waste, depleted uranium, or natural uranium close to completion. See Apparently, we currently have enough depleted uranium stockpiled (in the US) to provide enough power for the next 700 years.
Well this should make America Great -- NOT. The president who knows little or nothing about science and technology and apparently very little about basic economics is going to cut the basic research that drives the economy and then expect that the economy will grow faster. About 40 years ago, I had NSF funding that supported my doctoral work in robot assembly. This work led to a startup company. The products that I helped design are still be produced. Later about 20 years as a research professor, I had NSF funding that helped support work on CNC manufacturing directly from computer solid modeling. This also led to a startup company that is going strong although I am no longer involved. Kill basic research and in a few years, there will no longer be new innovations.
As long as you have cash, you get to stay in business. At some point, they will need to turn a profit. Personally, I would not buy Tesla stock at it's current price and I do not think that Tesla as an enterprise is worth more than either Ford or GM however neat their vehicles are. I do wish them them luck and do hope that they manage to stay in business and eventually reach breakeven.
A new version of peak oil.
Given that Proterra is offering battery electric transit buses with up to 660 Kwh of battery capacity, I think that most of the drayage could be done with battery electric vehicles. If you assume that the fuel cell is running an average of 75% of full capacity or 60 Kw for the class 8, 660 Kwh would last 11 hrs. Even at full capacity, it would last 8 hr and the class 6 and 7 trucks with only a 40 Kw fuel cell should be no problem for battery electric. I do not know the economics but from Proterra's cost projections showing that the battery electric transit buses are simply cheaper to own than diesel buses, I am guessing that battery electric trucks would be cheaper than fuel cell plus battery although the required battery is much less. The fuel cell trucks may be emission free but the hydrogen generation is not. Most hydrogen is reformed from natural gas. Even if it is generated from renewable electric sources, this is electric power taken from the grid that must be replaced but other power including coal fired plants that I live down wind from.
With current battery technology, long haul trucking is not likely to be a reasonably application for battery electric. maybe this will change if lithium air batteries become practical. (I will have to wait and see what Tesla has in mind). However for drayage operations including some city operations where top speeds to not exceed 40 mph or so and there is considerable stop and go, most of it can be done with battery electric tractors. The yard goat operations are already being done with lower speed battery electric tractors.
Thermal efficiency? This might be an interesting range extender for a small electric plane if the efficiency was not too low -- say greater than 25%.
HarveyD The Proterra buses are available with up to 660 KWhr of energy and 350 miles of range. It is hard to imagine that this is not enough for any reasonable transit system and if you believe their data, they are cheaper to own and operate than a diesel bus. Why would you want the problems of dealing with hydrogen fuel cell?
"electricity and renewable energy to generate clean hydrogen" Electricity from the grid including coal fired power from Nevada and Central Utah? I think that this application would be better suited for more efficient Battery Electric Buses as Proterra buses are available with up to 350 mile range and the New Flyer Battery Electric buses must be capable of at least a 200 mile range.
I am a little unsure what the purpose of this truck is. If they are just moving containers around the terminal or other relative short distances, the Orange BEV is probably a better choice. See The truck shown in the pictures looks more like a long haul truck and battery electric probably will not work for long haul trucking with current battery technology. But drayage implies short haul.
If it was April 1 and not April 17, I would have accepted this as an April fools day joke.
ai vin From the load carrying capacity is 2200 lb and the towing is 5000 lb with a crew of 5. This is roughly equivalent to a 1/2 pickup ton with a crew cab but not equivalent to a 3/4 or 1 ton diesel pickup with a full size bed. However, if you do need to tow a backhoe tractor to the work site or carry a full load of 4x8 sheets of plywood, the Workhorse pickup may be cheaper to own.