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sd
Utah
Doctorate in Mechanical Engineering, entreprenuer
Interests: diesel and gasoline engines, cars, aircraft, railroads, electric drives
Recent Activity
HarveyD I wish you were correct and it was so easy. However, the largest on-shore wind turbines, I could find were 3.2 MW from GE and 3.3 MW from Vestas. There are limits to how large a blade can be and still be transported and how large the diameter of the tower can be and still be transported. Vestas has built a 8 MW off-shore wind turbine and that apparently is the largest to date. Most commonly, the on-shore wind turbines that are presently being installed are about 1.5 MW. These numbers are the rated power and for on-shore wind farms, you are doing very well to average 20% of the rated power. So if you take 1000 MW for a new nuclear plant and 2.5 MW for a very large on-shore wind turbine and then take the average output to be 20% of that or 0.5 MW, it will take 2000 of these wind turbines to equal the power of the nuclear plant and I think that I am being generous with the numbers. I would like to see a verifiable reference for wind turbine power being produced at 2.0 cents to 2.5 cents per kWh As I said in a previous post, about a month ago I flew in a private plane from Utah to Wisconsin and back. We flew low enough so that it was easy to see the wind turbines on the ground in Wyoming, north western Nebraska, and southern South Dakota and Minnesota. Almost none of the turbines were rotating and I think I could have counted the turbines producing power on my fingers.
I have a hard time understanding why some many people fear nuclear power and favor wind turbines. If you throw out the Chernobyl disaster, there have been more fatalities involving wind turbines than nuclear power. It takes several thousand wind turbines to generate the power developed by a nuclear power plant. The rotating equipment has to be maintained at a height that is often 100 m (~330 ft) or more above the ground. There have been numerous nacelle fires and blade failures and even some complete tower failures. For more information on this than you ever wanted, see http://www.caithnesswindfarms.co.uk/fullaccidents.pdf The main problem with nuclear power has been the spent fuel and now there are a number of newer designs that will essentially burn the waste and the so-called depleted uranium. There is nothing that is truly safe but I would rather live near a nuclear power plant than a wind turbine farm.
HarveyD If, by this small firm, you mean Sakti3, Tesla would be about 4 years late. http://wheels.blogs.nytimes.com/2010/09/09/g-m-ventures-invests-3-2-million-in-battery-company/?_php=true&_type=blogs&_r=0
HarveyD The 1.4 liter turbocharged Ecotec engines for the North American Market are made in Flint, Michigan. I am not sure where the automatic transmissions are made but I am reasonable certain that they are either made in the US, Canada, or Mexico. A few parts are probably imported from other countries including China but most of the car for the North American Market will be manufactured in North America. These are global cars and are designed for a global market. It was introduced in China but as the article notes most of the testing was done in Germany. I am glad to see GM is using a dual clutch transmission as I believe that this will be the most efficient type of transmission both for economy and driving performance.
HarveyD I am quite sure that the sedan as shown will be built in the US for the US and Canadian markets. The US Cruze is manufactured in Lordstown, Ohio. The Cruze is also manufactured in Australia, Brazil, China, India, Kazakhstan, Russia, South Korea, Thailand, and Vietnam. In some markets there are also hatchback and wagon versions. The current Cruze is a nice car but the new version looks to be quite a step up.
ai_vin F(drag) = CD * Area * Air Density * Velocity * Velocity / 2 and if you SI units, the force will be in Newtons. The point that I was trying to make is that these cars are not aerodynamically efficient and that our understanding of aerodynamics has increased dramatically in the past 50 years. A Chevy Cruze would have less aerodynamic drag than these cars.
I can not believe that anyone with a knowledge of engineering and/or physics can believe that we can realistically generate hydrogen from wind or solar power. Just to provide the electric power that we now require using wind power would require covering the area twice the size of Wyoming with wind turbines using the recommended spacing (I picked on Wyoming because it is a neighboring state with wind turbines and I had seen a pro-renewable energy presentation that showed that it would take an area at least the size of Utah but Utah has really bad wind conditions and when I did the calculations using what I considered reasonable assumptions and the recommended spacing between the turbines, I got about twice the area). Simply put, we will not have excess wind power (or solar) to waste on electrolysis. If you do have renewable electric power, it makes far more sense to use it to replace some electric power now being produced using hydrocarbon fuels. As an aside, I recently made a low level round trip flight from Utah to Wisconsin and went over quite a number of wind farms. Almost none of the turbines were turning. I think that I could have counted the number of turbines that might have been producing power on my fingers. All I could think of was, "what a waste of capital equipment".
"physics doesn’t change much over time." The physics does not change at all but our understanding of aerodynamics has changed dramatically. I was stunned to see that the CD (coefficient of drag) of an E-Type Jaguar was 0.44 while most current street cars have a CD of about 0.30 to 0.33 and some practical cars are even less than 0.30 and a few semi-practical cars have a CD less than 0.20. Beautiful cars -- both the E-Jag and the LeMans Cobra but they are not efficient either as race cars or street cars. This car was made to be looked at.
Fuel cells are so early 19th century technology (1838 to be exact - http://en.wikipedia.org/wiki/Fuel_cell ). Talk about a technology that has taken a long time to mature. Seriously, the real problems are with generating and storing hydrogen. Probably, the only practical clean source of hydrogen is high temperature disassociation or high temperature electrolysis using nuclear power and even then you are probably better off just using the electric power for other needs.
Short of some magic lithium air batteries, this is probably the most practical way to electrify heavy trucking. I would rather see electrified railroads but the shuttles they are talking about are moving the containers from the ports to the railroad yards.
@Otis The aircraft diesels will run on Jet A or on the common #2 diesel and should also run on the military JP-8. The US military tries to run everything (trucks, tank, aircraft) on JP-8
Amazing. An aircraft engine that does not use 1930's technology and does not require 100 LL (100 Octane Low Lead) which contains a know neural toxin. I attended the Oshkosh airshow earlier in the week and looked at some of the Continental Diesels. I am building a light sport STOL aircraft and have a 115 HP Rotax 914 engine which is a liquid-cooled turbo-charged spark ignition engine that will run the higher octane automobile fuel. I would rather run a diesel but the ones currently available are too large and too heavy for my purposes.
I will echo Herman's "Well Done" comment.
Every time I see a prediction like this I am reminded of Yogi Berra famous quote -- "It is really hard to make predictions, especially about the future." Navigant is just some hired gun consulting group. These types of predictions are usually wrong as they do not know what types of break-throughs will be made in the next 20 years.
Part of this effort was a research project and there is value in knowledge gained. However, the total energy is only 2 KwHr which is not that that large for a Lithium Ion battery. And to emphasize electric-car-insider's comment, they should state the overall system efficiency.
SJC Not a big deal but just for the record, I am a practicing Mechanical Engineer with 3 degrees including a doctorate in Mechanical Engineering from MIT along with a degree in Physics. I have designed springs and taught others how to design springs. I used to teach the senior design class in the local University and still am the adviser for students competing in the FormulaSAE competition so I know a fair amount about springs and suspensions.
SJC I know that the Corvette uses leaf springs. They have 2 cantilever transverse leaf springs, 1 for the front, 1 for the rear. It is a relatively clever system that keeps the unsprung weight down. However, I would argue that a spring is a spring and they managed to replace what would have been a piece of steel with a lighter material that is also corrosion resistant.
OK but this is not really new. GM has been using glass fiber-reinforced polymer (GFRP) springs in the Corvette for at least a decade. I do wonder why they use glass instead of carbon fiber which is even stronger for the mass.
Almost 45 years ago (spring of 1970), I was a master's student in Mechanical Engineering at MIT and was attending a weekly seminar in fluid mechanics. The inventors of the magneto-rheological fluid came in and gave a seminar on the properties of this fluid and had some demonstrations. I remember that they did not have any particular use for the fluid and were not sure what it could be used for. However, it had some interesting properties which they thought might be useful for something. Sometimes, it takes a while to go from lab curiosity to practical use.
This article is rather loose with the numbers and the math. How do you reduce the NOx emissions by 457%? Reducing it by 100% would imply no emissions. Also some of the reduction assumes that a diesel engine is replaced with a gasoline engine plus their hydraulic hybrid system. It would probably be more efficient to replace the hydraulics with ultracaps and an electric drive but it might not be less expensive.
I would like to know more of the technical specs on this engine and how they manage to run cleaner than a 4-stroke engine. Unfortunately, they do not have any cutaway drawings in their literature. Are they using the back side of the piston for pumping as is common for 2-stroke engines or do they run a separate pump/supercharger? Are they running exhaust after treatment? Most likely. Anyway, these engines are not light. The 300 hp engine weighs 558 lb
HarveyD Yes, this was only a engineering concept car. However, as they said: "Our goal was to investigate how to design and build a mixed-materials, lightweight vehicle that could potentially be produced in high volume, while providing the same level of safety, durability and toughness as our vehicles on the road today." This type of engineering research work usually proceeds actual production engineering. You might also note that their research has also led to a weight reduction of 700 pounds (318 kg) in the new production F-150 through the use of high-strength steel and aluminum.
It all depends on how you drive. I once drove a colleague's older Prius and got about 40 mpg. I was immediately told that I should have gotten about 50 mpg but I was driving as I would have driven any other vehicle and not trying to hyper-mile.