Posted on 07/20/2011 7:32:01 AM PDT by Liberty1970
I’m a lot more skeptical of the on-demand motive power your micro-sized (by necessity) steam engine than I am of the actual E-cat. There is only so much room under the hood of a car, particularly a small one. The E-cat units, the electricity generator and battery will use a lot of it. Leaving not so much for a boiler and pistions, your “pressure accumulator”, hydraulics, etc. But whatever, it’s fun to speculate.
> Why? A two or even three phase turbine wrings most of the heat and energy out. Open loop would be a problem such as steam engines had where they had to stop very often for “fuel”
1) The steam engine in this case would be optimized for power-to-weight ratio, reliability, and low cost. Thermal efficiency would probably be 30% or less. Therefore to get about 45hp of mechanical power you’d need to radiate about 75KW of thermal output. That’s quite a bit for a small car.
2) Yes, an open cycle steam engine would need frequent ‘refueling’ with clean water. It would probably have a range under 100 miles before it would need more water, even with a pretty large water tank. So? Water is cheap, and is available just about everywhere.
> Long-term, closed cycle would be the way to go. But if someone wants to sell a E-cat powered car next year - basically it would have to be open-cycle steam.
Alternatively, think of a sodium/sulfur battery electric car with a single 35Kw(t) E-cat battery warmer/self recharger, using a Stirling cycle for the generator.
That could be cost effective.
Agreed, except for the one thing about convenience. I am used to filling my SUV up and going 500 miles before I have to fuel up. Even Mrs. Mad’s small car has a 500 miles range on a tank of fuel. Out here in the West 100 mile range would be very painful outside of the city. Modern turbines give great power to weight ratio. That said I was recently on the USS Midway. In a tour of the engine room I got into a long discussion with one of the docents about the efficiency of their turbines (double turbine high and low on one circuit) surprisingly small units for 30,000hp.
From reading all your comments, it seems clear that an E-cat powered car would definitely be a “green” type of car: Small and rather low-powered. Those needing more muscle in their auto/truck could stick with petroleum powered vehicles. The great thing about E-cat powered car is not having to stop for fuel or for battery charging. I am assuming that once the steam engine system is filled w/ water or other fluid that it is a closed system that won’t often need additional fluids.
But I don’t really know, I am a highway engineer not an ME.
“LOL. There are thousands of “steam engineers” around the world, and the centuries of technology certainly hasn’t gone away. And the cure for all the above mentioned are easily done. At night, just keep the e-cat “ticking over” at a low level, just like truckers do when they stop for lunch. Fast acceleration energy stored in a “pressure accumulator” (see pneumatic and hydraulic drive car prototypes). Electric drive/energy storage NOT needed except for cold startup and running the radio and other accessories.”
There is a reason that the railroads gave up the fuel flexible steam engine and went to diesel.
That accumulator would act very similar to a bomb if ruptured. No 5 star crash rating for it.
Steam give excellent torque but is very heavy and doesn’t give great peak HP. It would be a lot like driving a train, 0-60 by noon.
“At least initially, E-cat units are not going to be so cheap. I read that Rossi is planning on pricing a 35Kw(thermal) E-cat at 5000 Euros = $7k”
True, but that pricing is probably based on what he thinks the market will bear, and the fact that initially he will have a monopoly. The little that has been disclosed regarding its construction suggests that the cost should be significantly lower in a normal market situation.
Electronic control of the "tickler" input heat doesn't depend on the original source of the electricity that's generating the heat.
Thermocouples, RTDs, and the control circuits they drive don't care if the original electrical power is coming from the grid, a battery bank, or even an array of solar panels. (If the input power must be AC, an inverter can convert the battery or solar panel DC output to AC. If the input power must be DC, electricity from the grid needs to be rectified to DC anyway.)
Sure. Diesel was cheaper and easier to handle. And the E-Cat even more so. Had zip to do with the practicality or non-practicality of steam.
"That accumulator would act very similar to a bomb if ruptured. No 5 star crash rating for it."
Any newly graduated mechanical engineer could design one that "is" "5 star crash rated". No new technology at all needed there.
"Steam give excellent torque but is very heavy and doesn’t give great peak HP. It would be a lot like driving a train, 0-60 by noon.
There is this metal called "aluminum", which takes care of the "very heavy". And as said previously, "peak" power would be supplied by an accumulator.
Of course that's all true, but remember that one of Rossi's target markets is industrial heating, so he is looking for an E-Cat that "can" be controlled based only on working fluid flow rate, which he has apparently succeded in doing.
And I think he'd like to come up with more and larger E-Cats that exhibit similar characteristics.
“Any newly graduated mechanical engineer could design one that “is” “5 star crash rated”. No new technology at all needed there.”
“There is this metal called “aluminum”, which takes care of the “very heavy”. And as said previously, “peak” power would be supplied by an accumulator.”
Really?
How much do you think that 5 star accumulator is going to weigh? You are going to need to either make it very small but that is going to require extraordinary pressure and materials to match or large but then you have the problem that wall tension is based on both pressure and area and you will still need very thick heavy walls.
Where is this acculator and the insulation to keep it hot going to sit?
As far as using aluminium, it would make more sense to spin turbines and use the power to reduce aluminum and run cars on mechanically rechargable aluminium batteries.
LOL. You're obviously not familiar with the new research and engineering in ultra-high pressure composite tanks, good to 20,000 psi, and weigh virtually nothing. Think "carbon fibers" or some of the new VERY high tensile strength polymers.
"Where is this acculator and the insulation to keep it hot going to sit?"
Probably right next to the E-Cat. Saves on insulation.
"As far as using aluminium, it would make more sense to spin turbines and use the power to reduce aluminum and run cars on mechanically rechargable aluminium batteries."
Not really. Remember, the topic we're addressing here is what can be built QUICKLY that doesn't require lots of additional technology. Ultimately, a steam/hybrid electric "does", I think, make the most sense. But that will take longer to get out of development.
“LOL. You’re obviously not familiar with the new research and engineering in ultra-high pressure composite tanks, good to 20,000 psi, and weigh virtually nothing. Think “carbon fibers” or some of the new VERY high tensile strength polymers.”
Great material, Very high tensile strength, very good at keeping pressure it, not nearly as good at keeping things out, you will need a different material for your 5 star crash rating. Go down to a welding shop and look at what the tanks are made out of.
Spinning a turbine to make electricity and running on electricity is doable and they already make a DOT approved accumulator, it’s called a battery. If you don’t mind spinning the turbine all the time and have a big battery, you wouldn’t need to make more than a couple kW to have a vehicle that would meet average driving needs.
Couple cheap E-CAT electricity with a graphene power pack and gas stations will be a novelty.
Plug the SUV in, go inside for a cup of joe, and hit the road again. Flip off OPEC just for the fun of it.
http://green.blorge.com/2011/07/new-batteries-made-from-graphene-and-water-recharge-fast/
Would put Al Gore and the carbon dioxide Nazis out of business for good measure.
Tanks in welding shops are metal because it is cheaper. But if you actually look at some of the more updated tankage for storage and transport of gases, they are bi-layer, with a much thinner metal inner liner (composites have a higher permeation loss rate than metal) and a composite outer shell. If you've ever watched an "Air Products" (or similar specialty gas delivery vendor) truck deliver gases, they take FAR more abuse than a tank on the interior of a vehicle is ever likely to. And many of those are now composite.
"Spinning a turbine to make electricity and running on electricity is doable and they already make a DOT approved accumulator, it’s called a battery. If you don’t mind spinning the turbine all the time and have a big battery, you wouldn’t need to make more than a couple kW to have a vehicle that would meet average driving needs.
Re-read the last sentence in my comment.
“If you’ve ever watched an “Air Products” (or similar specialty gas delivery vendor) truck deliver gases,”
OK, you were the one making fun of me because I’m not an engineer, but come on, now you are talking about refrigerated gas containers, completely different from high pressure tank construction.
Why would it have to be a compact car?
Chug-a-chug-a Chug-a-chug-a whoo whoo whoo! "Can I blow the whistle dad?"
I remember talking to some old-technology ship turbine operator who spoke of bubbling the expended turbine gases through the condensed liquid in a sealed system, thus causing rapid (almost violent) condensation, and not just a low pressure side, but an actual negative pressure on the low side of the turbine.
The condensed liquid was then pumped back into the "boiler" for reheating.
Of course in a closed system, other coolants/refrigerants/propellants would likely be superior to water.
>> For a compact car, they probably would be too big.
> Why would it have to be a compact car?
> Chug-a-chug-a Chug-a-chug-a whoo whoo whoo! “Can I blow the whistle dad?”
It wouldn’t HAVE to be a compact car. But if you consider a $7000 e-cat which only delivers ~15hp, unless you are going for the > $60,000 car market, you’re looking at limiting your car to about 60hp.
If the design is a hybrid, with an oversize ultracapacitor to give you good 0-60 accelleration, 60hp could probably be enough.
It isn’t enough to produce a car that has near-zero fuel costs, if the car costs more than an equivalent gas-powered car and 150,000 miles of fuel.
No. Compressed hydrogen, helium, nitrogen, oxygen, and pretty much every other high pressure gas can be had in such composite cylinders as well as metal. They also use'em for scuba tanks, which contain similar pressures. Where did you come up with this idea of "refrigerated gas containers"?
I don't know the full extent to which composite has replaced metals, but I've seen plenty of such tanks in cylinder storage racks, and they weren't for refrigerated gases (though composite cylinders can also be used for those).
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