Don't be fooled that "hey they are solid state and convert directly to electricity". Deep down, it's still a physical process that produces electricity, even if the moving parts are not something you can see. In actual practice, what happens with these things produces horrible efficiency.

These electronic devices are semiconductor junctions that you get heat to flow through in hopes the electrons will bounce their way across the junction into the cooler side and get stuck... They are not efficient from a thermodynamic perspective, and unless my physical understanding of how they work is totally wrong, they are never going to approach the efficiency of even an internal combustion engine, from a thermodynamic perspective anyway.

If you read my post.... (and apparently you didn't) ... I specifically stipulate that automotive applications *might* be successful and worth of investigation. The reason I say this is because of the huge amounts of heat transferred out the tail pipe and radiator in a modern internal combustion engine at sometimes very high temperature differentials leaves something to recover. This is totally unlike a modern power plant, where heat transfer has been carefully engineered to be as efficient as possible, thus leaving little room for thermodynamic improvement. However, my doubts about automotive application are over costs, weight and complexity not about the Thermodynamics of the application.

Until these devices they describe approach the current efficiency of a power plant, there is zero chance they will be helpful on an industrial scale. Modern power plants are usually within a few percentage points of ideal so these devices are going to have to come way up the efficiency scale, and they are horrible now. Given how they work at the subatomic level (holes, electrons etc) I seriously doubt we are in any danger of reaching this level.

I'm not sure how the cooling works for PV cells. But, if they are actively cooling the liquid there is little to be gained from this arrangement and it is likely going to lead to hotter cell temperatures and cooler liquid temperatures.

So it *might* work, but only if the temperature differential they can stand is high enough and they are not expending energy to cool the liquid through some heat engine.... (I.e. if they use something like a swamp cooler or something.)

Here we go "waste heat". Please learn a bit more about thermodynamics and heat engines. Power is generated from the TRANSFER of heat. Power plants are huge heat engines, that produce electrical power by taking heat from a high temperature source, transferring that heat to a low temperature sink. There is very little WASTE in a power plant (nuclear or otherwise). Yes you have to dump heat to generate power, but it is not like you are just wasting power when you dump heat. This "waste heat" is not a free resource you can exploit to get more power from the plant.

Adding any other devices in the path of the heat flow will only impede the heat flow and drive down efficiency. I contend that the loss of efficiency will be more than the power you can generate using devices that directly convert heat transfer to electrical power. These devices are not nearly as efficient as what we have already in a modern power plant, thus there is zero chance they will be better.

If 50 min is all it takes, then why as it not happened? Surely there is some nut job out there crazy enough to do it and smart enough to pull it off. Surely... It's not like all the folks in the middle east are somehow stupid, and a lot of them have serious issues with the USA and would love nothing more than to put us all in the dark, if even for a short time. Wide spread outages, caused by somebody hacking, simply have not happened. Why? If it is so easy, surely somebody would have tried it by now because there are a lot of smart people out there who would be willing to do it.

I strongly suspect you are making stuff up now.. So this is where we stop.

Unless the guy behind you has one too and thinks it's your fault..

Which is why I stipulate that these heat to electricity devices MIGHT be of value for internal combustion engines. The heat dumped by them is significant and the temperature differential quite high. There is at least opportunity to get something that would normally just get dumped. I just openly wonder if for a car or truck it will be worth the cost, weight and complexity it will add. I strongly suspect that it's not worth it, but I'm not totally sure.

Calm down and think about what I said. Your average power plant is pretty darn good efficiency wise (which is what I said if you don't mind reading), which is exactly what you are saying too. Yea, we've come a long way from just dumping waste steam, we have optimized things very well actually. I'm saying that there is very little room for improvement left at this point and there is NO FREE LUNCH here. These devices that convert heat flow directly to electric power are NOT going to increase the efficiency of industrial scale power plants. These devices are simply NOT EFFICIENT enough and will disrupt the current efficiency we've already designed in, they will only disrupt the heat flow, raise entropy and result in less power output for the same input. They don't help.

What on earth did I say that was incorrect? I admit to having struggled with thermodynamics class, but I believe I captured the essence of heat engines and efficiency. So you want to step down off the pedestal and discuss exactly what you think I have wrong in my understanding of thermodynamics? Or are you going to stay up there and keep yelling about how stupid everybody else is?

LOL Why yes, yes we do. Like it or not.

I don't know about you, but I've been talking exclusively about the power grid.. Which was what the original article was about.

If you want expand from there, I've seen Y2K problems as recently as a month ago. Not that it mattered that my sprinkler controller isn't Y2K aware. First of March, just pick a year that starts on the right day of the week and it will work, at lest until the end of February. All you have to do is ignore the year in the mean time.

I never said Y2K wasn't a problem, only that all the yahoos who thought the Apocalypse was upon us as we approached January 1, 2000 and the grid was going to fail and the banks where going down too, where out to lunch. As out to lunch as the crazies who are saying the same thing about cyber warfare taking down the grid now...

I debunked this LAST time it was posted..

Look, these things are NOT going to get you thermodynamic efficiency gains on anything of value. Any system which is designed to be efficient now, will not benefit from this kind of heat to electricity device. Thermodynamic rules demand a maximum efficiency that is as good as you can do. Most industrial scale energy production is pretty darned good compared to the maximum possible. So you are NOT going to be able to just hook up these things and get electrical energy for *free* (even without the device costs). Any energy you manage to get, will be lost someplace else because you put these devices in the heat flow. Don't even bother trying this, it simply won't work. Don't let them fool you with all this "waste heat" garbage, at least until you understand the Thermodynamic laws that govern all this and can explain what a heat engine is.

As I concluded before, in situations where you have less than ideal conditions, like in cars with internal combustion engines, you MIGHT get a little bit of energy, but I ask you is it going to be worth it? Are you sure you are going get enough gain to make it worth the weight, cost and complexity? Where I'm not so sure that answer is a good one, I'm willing to entertain that it *might* be possible for internal combustion engines. Go ahead and work on that idea, but I'm fairly sure it's not going to work very well.

I'd also suggest that there are more efficient heat engines you might consider. These heat flow direct to electricity devices are horribly inefficient compared to the ideal.

My lights stayed on pretty much the whole year before and the year after... But I suppose...

Really?

I'm comparing the historical FUD that came BEFORE January 1 2000, with what I'm calling FUD about cyber attacks today. Come on it's not that hard..

IMHO, the risk of a Y2K issue on January 2nd, 2000 was higher than a successful cyber attack is today.. (Yes, that's a full 24 hours after the 2 digit year rolled over..)

Your mileage may vary.