Topic: Thorium power, how is it going in the US? - page 6. (Read 11245 times)

Most things can explode and catch fire if sabotarged enthusiastically enough.

I did not argue that solar is infinitely scalable on the land mass of the US.  It certainly has huge room to grow though.  The main thing is that at this price point, solar will save you money to convert to if you are going to live in your house for a long time.  Government resources are going into this through 30% solar tax credits because this is the thing that will reduce energy dependence, and energy dependence is very bad for the. US

We are not trying to scale land-based solar to 100% of US electric energy consumption.  As soon as private industry lowers the cost of space launch, panels will be put into orbit where the sun never sets and the sunlight is 5.5x stronger.  We have recently had a private space launch, and private industry is very good at reducing the cost of things that the government pioneers.  Also, are you aware that nuclear energy is about equal with fossil fuels in overall cost per KWH?  Once they are built they can make energy very cheap, but the initial startup cost is insane.

Here is a rough calculation:
Residential electric energy consumption is 35% in the US
There are 80 million single family homes in America out of 130 million housing units.  So presumably, somewhere around 62% of the housing units can have solar panels on the roof which power them. So 22% of total US electric energy could be done on single family home roofs.  The true number would be adjusted up as I would think houses use more electricity than apartments.  It would also adjust down by the percentage of cloudy days.

I resisted giving you a LMGTFY link...

https://en.wikipedia.org/wiki/Temperature_coefficient#Temperature_coefficient_of_reactivity

The energy density of the sun is irrelevant, what matters is how much of it reaches the Earth's surface. The day time peak is roughly 1000
watts per square meter at the average latitude of the US, or approximately 100 watts per square foot in old currency. The best solar panels currently are only about 20%  efficient and it will be very difficult to get past 30% or so.  For the reason why, you need to understand the Carnot limit, see:
http://en.wikipedia.org/wiki/Carnot's_theorem_(thermodynamics)

These numbers adjust downwards for time of day, time of year, percentage of cloud cover, etc., not to mention the problem of storing the energy when the sun does not shine. Every time energy is converted to another form there are conversion losses which do not occur in forms of energy production which can dynamically adjust to the immediate demand as is the case with nuclear and fossil fuels.

Solar energy is so inefficient it would take covering an area the size of Texas to supply the energy needs of the US even discounting the storage and conversion losses mentioned above. Thus, because fossil and nuclear power generation has relatively small foot prints they can easily be put near where the power is needed. Solar would have to be put significantly farther away (assuming the land is available at all), which means greater line losses to transport it, at least until someone manages room temperature super conductivity.

You have no idea of what you are talking about. There is simply no need for higher energy density than the sun already provides. The amount of energy received on the roof of the typical family home is enough to power it. And yes they will become almost 100% efficient. Lookup nantennas and weep.

Besides bitcoin mining, heavy industry, things like that...

The price of solar panels could drop to zero and they still will not generate energy competitive, short of through subsidies, with chemical much less nuclear forms of energy. The cost of the panels is irrelevant, what matters is energy density. Nuclear fission is 1-2 million times more energy dense than any chemical reaction, fusion is about 8 million times more dense, and chemical reactions are several orders of magnitude more dense than solar. I seem to recall someone calculating that it would take covering an area the size of Connecticut with solar panels just to meet the energy needs of NY City.

So even if the panels were both free and 100% efficient, the amount of land required makes it prohibitively inefficient up against an 8+ order of magnitude disadvantage in energy density.

The US is not going to spend billions developing Thorium reactors.  All the research money has gone into solar and it has paid off now that the price of solar has dropped 75% in the last 3 years.  Global energy production from solar went up 193% last year.  Solar is the future.  Here's a relevant post I made in the gas prices thread:

I made a conceptual drawing of my idea:

 

Rather than trying to use kickstarter for what is probably a multi-billion dollar effort, one might consider looking into what is happening with LENR (Low Energy Nuclear Reaction).  While it is really a renaming of the much maligned "Cold Fusion", it is becoming increasingly evident that it is real. Three companies have announced the immanent release of products or licenses, Leonardo Corporation (Italian / US), Defkalion (Greek) and Brillouin (US).

The most promising work appears to be with fusing Nickel and light Hydrogen to produce copper. Its advantages include the ability to do it inexpensively on  a very small scale (table top), results in a very small amount of radiation which is easily shielded, and is fail safe because if it overheats it apparently disturbs the Nickel lattice to the extent that the reaction cannot continue.

Leonardo corporation has announced three products, a 1MW unit which fits in a shipping container of which at least one has been delivered, a 10KW E-Cat (400 C) and the most recently "leaked" Hot Cat which can generate heat in the 1000C to 1200C range, i.e. hot enough for fairly efficient generation of electricity. Early indications on the pricing for the 10KW E-Cat is that it will be under $1000 US.

Additionally, there are several open source efforts already under way, including a high school in Italy which has published a laboratory design which claims a COP (Coefficient of Power, or power in to power out) of 4. There is also an open source project at:

http://www.fusioncatalyst.org

And lots of information on LENR in general at these blogs:
http://www.ecatnews.net
http://www.e-catworld.com

As I understand it your saying there are two parts that should be seperate because it makes things simpler.

Can we not have them separate, even to the point of interconnecting pipes and the such, all without cooling? What part needs to be cool?


Are we including converting the heat to electric as well, other industries can do this as they see fit, lets stick to the hard part.

Yes placing the reactor inside the resonator would be more efficient. But how do you dismantle the thing once it is no longer operational?

Also I am not sure if there is a piezoelectric material which is suited for the purpose. Attaching linear actuators directly seems kind of dangerous.

I read could be pint glass sized earler, here:
http://www.telegraph.co.uk/finance/comment/7970619/Obama-could-kill-fossil-fuels-overnight-with-a-nuclear-dash-for-thorium.html

The hole in the middle of the torus seems like a good place for the rest of the stuff.

Cooling cycle, wish we didn't need that, I thought we wanted hot, is the arogel not going to cut it, how about that metal jet engines are made of?

Wouldn't water in a hot machine not stay ambient in temperature for long?

Should work.

Ideally such a unit should be small enough to be transported in a standard shipping container, which contains a torus shaped resonator in which the reactor is contained on one end and the other end some piezoelectric material which directly converts the vibration into electicity. Then there should be enough space left for the transformer, power electronics and maintenance equipment.

 
like this:

Just attach the cooling cycle instead of the air convector and your done.

Make from metal coated (on the outside) Aerogel?

Good, I'm glad we got that settled.

But that brings me to my next nagging point:

In order to archive a better Carnot Efficiency the reactor design has to be built as hot as possible. Quite simple the hotter the reactor can run the more economical it is. So the engineers are pushed towards going to the limits of material safety.
So even if the reactor is safe, the attached machinery is most likely constructed with little operating margin.
So in order to get rid of this issue we need a heat machine which can operate on the same operating margin as the reactor itself.

Steam Cycles will always have higher material safety requirements because of moving parts (turbines, valves) and they are prone to corrosion.
I suggested thermo-accustic generators which can be built out of the same heat-resistant materials as the reactor giving engineers a uniform material safety requirement.
Plus they are as down-scalable as the reactor design (even more so) while maintaining peak efficiency across the board. So this would make it possible to engineer small power modules which can be switched on/off on demand and transported as a whole unit.

An exaggerated claim, yes; but to say that there is no basis in reality is not quite true.  In a 'meltdown' (the kind that laymen think of, anyway) the core melts due to excessive heat buildup as a direct result of a runaway, super-critical reaction; thus a 'cascade'.  If the cascade is almost impossible, to say that they are temp limited is a fair claim for a basic understanding of the science, even if it's not technically true.

Please don't discard the context of that sentence.
To make that clear, I say the claim that it cannot melt down is bullshit because the claim that the reaction itself is temperature limited is bullshit.

As of design, it can be very meltdown proof, but any design can fail.
Again: Thorium Reactors instead of Uranium Reactors, I'm all for it, do it. But I hate exaggerated claims which have no basis in reality.

Correct about the ET part. The training manuals the Navy uses aren't classified for the science in them; they are classified because they talk about specific design features of naval reactors, and sometimes classified details of other military experiments/prototypes. The basic science of how fission works and now reactors are designed in general is public knowledge and has been for decades.
Any solid object can melt under the right conditions. It is, however, possible to design a nuclear reactor in such a way that the fission that takes place inside it is incapable of producing those conditions.

If "meltdown" is understood to include the effects that are associated with traditional reactor failures such as explosions, fire, plumes of radioactive material being injected into the atmosphere, and a molten blob of radioactive material melting its way into the ground then it is entirely accuate to say that "meltdown" is impossible in a LFTR design because the elements which produce those outcomes in a solid-fueled reactor do not exit.

Okay, yes.  That's hyperbole.  Any reactor design can melt down, but some have inherently designed features that resist a cascading reaction that would lead to a 'meltdown' as in Chernobyl.  Those features make such an event very unlikely, but never impossible. 

I have no problem with any of the arguments of why thorium reactors would be better than uranium ones. Including that they can be safer.

I even recognize that they could be built self regulating. (But again see my ramblings about Carnot efficiency of why this is not practical for steam generating designs)

I just maintain that the claim that they can not melt down because the reaction itself is temperature limited is bullshit.