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I don't know where you keep getting this idea that I think a heat recovery turbine is simpler than a generator. All I said was that if you think a heat recovery

I don't know where you keep getting this idea that I think a heat recovery turbine is simpler than a generator. All I said was that if you think a heat recovery turbine is too complex to be feasible, then you'll also think an electric motor is too complex to be feasible. Because neither are too complex to be feasible. And no, it is not complex at all. The turbine part stays the same as your garden variety turbocharger. Instead of directly attaching a compressor (which makes it a turbocharger), you directly attach a generator (which makes it a turbine-driven generator). In fact, you could even do both: power an intake air compressor as well as a generator. Literally anybody could build one in their back yard using parts ripped out of random cars at a junkyard. Without capturing any waste heat at all, Solid Oxide Fuel Cells are ~60% efficient. With a waste heat recovery turbine, you increase the efficiency. 75% efficiency is already feasible. https://www.sciencedirect.com/science/article/abs/pii/S0306261918310316?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S03062... Yes, this solution is more complex than a normal fuel cell...in exactly the same way that a turbocharged engine is more complex than a naturally aspirated engine. That is to say not only is it entirely feasible, but it is a well developed easily adaptible solution that has been used for increasing efficiency for over a century now. Learn how to google...there are literally hundreds of papers detailing efficiency gains from using turbochargers on fuel cells. Hell, most turbocharger manufacturers are already making custom hybrid turbocharger/generator packages specifically designed for fuel cell use. https://www.garrettmotion.com/electric-hybrid/twostage-electric-compressor-for-fuel-cells/ https://www.garrettmotion.com/electric-hybrid/twostage-elect... https://www.mtu-solutions.com/eu/en/stories/technology/turbochargers-for-higher-engine-efficiency.html https://www.mtu-solutions.com/eu/en/stories/technology/turbo... https://cdn.borgwarner.com/docs/default-source/default-document-library/2014_whitepaper_charging-system-for-fuel-cell-applications_en.pdf?sfvrsn=b60acd3c_11 https://cdn.borgwarner.com/docs/default-source/default-docum... You thought it was infeasible because you were imagining a big ass steam engine, and when it was pointed out that turbochargers are an entirely commonplace form of heat recovery turbine, you backpeddled and tried to redefine words (b-b-b-but that's a Turbo Compounder!!!) to weasel your way out of it. Give it up. You're embarrassing yourself.

SigmundA 5y ago
>If a modern heat recovery turbine is too complex, then so is an electric motor. A generator is bascially an electric motor running in reverse, at minimum you have a turbine and a generator to make a heat recovery turbine, or you can mechanically couple it with a transmission. That is more complex than just an electric motor, is this not obvious to you? The SOFC you linked at 75% efficiency uses a turbine with a secondary combustion chamber (post combustor) and along with a generator. Again this is not just a "simple" turbocharger. https://d3i71xaburhd42.cloudfront.net/3362b2a27c2ec1f3064114a66c9791721af69fe4/5-Figure1-1.png https://d3i71xaburhd42.cloudfront.net/3362b2a27c2ec1f3064114... Does that look like just a simple turbo charger? You are the one redefining what a heat recovery turbine is, no one calls a turbo charger a heat recovery turbine, and no devices called heat recovery turbines are just a turbo charger at minimum they drive a generator or are mechanically coupled to an engines output. So you have on one hand a: battery - motor controller - electric motor VS high pressure liquid H2 tanks - fuel cell - recovery turbine with generator - motor controller - electric motor Hopefully the fuel cell can have enough burst power for acceleration and not also need a buffer battery like current fuel cell EV's, then again you need a battery or regenerative braking, oh well. Which one is simpler and cheaper to fuel, maintain and operate? Which has more moving parts? Current fuel cells in cars don't even have an energy density advantage, maybe they will and will outpace batteries but they are certainly not simpler than a battery powered EV. Also stop being an ass, you are the one embarrassing yourself, at least try and keep it civil.
- darksaints 5y ago
  > Does that look like just a simple turbo charger? It doesn't look like a turbocharger, it looks like a system diagram of a fuel cell attached to a turbocharger. ::facepalm:: > You are the one redefining what a heat recovery turbine is, no one calls a turbo charger a heat recovery turbine, and no devices called heat recovery turbines are just a turbo charger at minimum they drive a generator or are mechanically coupled to an engines output. ::doublefacepalm::
  - SigmundA 5y ago
    Did you even read how they attained 75% efficiency on the SOFC with gas turbine? They fed 25% of the fuel to the gas turbine and it was creating at least 25% of the power, they then tried 45% of the fuel with a 50/50 power split. Is a gas turbine sitting next to an engine being fed half the fuel and putting out half the power a turbo charger? Did you miss the combustion chamber and generator for the gas turbine when you face-palmed? The Garrett link you presented isn't even a heat recovery turbine, it's just a electric compressor it draws electrical power from the fuel cell to compress the air. The other links are similar, they actually use power rather than generating it, they allow reduction in fuel cell size not increased efficiency: "The process temperature of modern fuel cells for cars is rather low. Therefore, the exhaust gas enthalpy provided to the turbine is not sufficient to drive the compressor. Hence, a powerful electrical motor is necessary to drive the compressor; in fact, it is an essential component of the FCAS system. Even a variant of the FCAS system without a turbine is available as part of the FCAS family." A turbo charger compresses air using heat, then rejects much of that heat in the intercooler very little of it is recovered as engine output power. Its purpose is to increase volumetric efficiency not thermal efficiency. More air + more fuel = more power with less displacement. A heat recovery turbine increases thermal efficiency not volumetric efficiency, that is the distinction between a turbo charger and heat recovery turbine in all literature I can find. They operate on similar principles and share a component (the turbine) but one is simpler than the other and they are not the same. Please show me a fuel cell using just a "simple" off the self turbocharger as a heat recovery turbine.

SigmundA 5y ago

>If a modern heat recovery turbine is too complex, then so is an electric motor. A generator is bascially an electric motor running in reverse, at minimum you have a turbine and a generator to make a heat recovery turbine, or you can mechanically couple it with a transmission. That is more complex than just an electric motor, is this not obvious to you? The SOFC you linked at 75% efficiency uses a turbine with a secondary combustion chamber (post combustor) and along with a generator. Again this is not just a "simple" turbocharger. https://d3i71xaburhd42.cloudfront.net/3362b2a27c2ec1f3064114a66c9791721af69fe4/5-Figure1-1.png https://d3i71xaburhd42.cloudfront.net/3362b2a27c2ec1f3064114... Does that look like just a simple turbo charger? You are the one redefining what a heat recovery turbine is, no one calls a turbo charger a heat recovery turbine, and no devices called heat recovery turbines are just a turbo charger at minimum they drive a generator or are mechanically coupled to an engines output. So you have on one hand a: battery - motor controller - electric motor VS high pressure liquid H2 tanks - fuel cell - recovery turbine with generator - motor controller - electric motor Hopefully the fuel cell can have enough burst power for acceleration and not also need a buffer battery like current fuel cell EV's, then again you need a battery or regenerative braking, oh well. Which one is simpler and cheaper to fuel, maintain and operate? Which has more moving parts? Current fuel cells in cars don't even have an energy density advantage, maybe they will and will outpace batteries but they are certainly not simpler than a battery powered EV. Also stop being an ass, you are the one embarrassing yourself, at least try and keep it civil.

darksaints 5y ago
> Does that look like just a simple turbo charger? It doesn't look like a turbocharger, it looks like a system diagram of a fuel cell attached to a turbocharger. ::facepalm:: > You are the one redefining what a heat recovery turbine is, no one calls a turbo charger a heat recovery turbine, and no devices called heat recovery turbines are just a turbo charger at minimum they drive a generator or are mechanically coupled to an engines output. ::doublefacepalm::
- SigmundA 5y ago
  Did you even read how they attained 75% efficiency on the SOFC with gas turbine? They fed 25% of the fuel to the gas turbine and it was creating at least 25% of the power, they then tried 45% of the fuel with a 50/50 power split. Is a gas turbine sitting next to an engine being fed half the fuel and putting out half the power a turbo charger? Did you miss the combustion chamber and generator for the gas turbine when you face-palmed? The Garrett link you presented isn't even a heat recovery turbine, it's just a electric compressor it draws electrical power from the fuel cell to compress the air. The other links are similar, they actually use power rather than generating it, they allow reduction in fuel cell size not increased efficiency: "The process temperature of modern fuel cells for cars is rather low. Therefore, the exhaust gas enthalpy provided to the turbine is not sufficient to drive the compressor. Hence, a powerful electrical motor is necessary to drive the compressor; in fact, it is an essential component of the FCAS system. Even a variant of the FCAS system without a turbine is available as part of the FCAS family." A turbo charger compresses air using heat, then rejects much of that heat in the intercooler very little of it is recovered as engine output power. Its purpose is to increase volumetric efficiency not thermal efficiency. More air + more fuel = more power with less displacement. A heat recovery turbine increases thermal efficiency not volumetric efficiency, that is the distinction between a turbo charger and heat recovery turbine in all literature I can find. They operate on similar principles and share a component (the turbine) but one is simpler than the other and they are not the same. Please show me a fuel cell using just a "simple" off the self turbocharger as a heat recovery turbine.