OK Ignore the fuel price. In work that has been done on exhaust heat recovery (where the heat is effectively free and temps 4-600 degrees C) for trucks and cars Rankine is popular (eg BMW with steam), and Brayton too (many trucks and ships use turbocompounding, recovering power from the turbine of a turbocharger, F1 will as well from next year), but I have never seen anyone try to use Stirling.
If you just look at the weight of a hybrid car LENR engine; stirling vs rankine vs brayton turbine the stirling is by far the heaviest, has the lowest operating speed (so bigger generator, belt or gearbox required), has a large number of high tolerance components, is made from high cost materials, has known issues with reliability, needs very large radiators, and needs a system for re-compressing leaked hydrogen. Which do you think will end up being cheapest to put in a car? I couldn't pick between Brayton and Rankine: Brayton (recuperated or not) probably has lower efficiency (10-20%), with lower density working fluid for heat transfer meaning large heat exchangers with large pressure differentials (ie big and heavy), very high bearing speeds a hassle, but no condenser required. Rankine, small, light, dense high pressure working fluid = compact boiler and engine (turbine or reciprocating), good efficiency (15-25%), but likely a large condenser. But what I am very sure of is that it won't be Stirling, even if it can manage 35% efficiency, it simple misses on too many other cost, weight and size factors. On 6 February 2012 22:39, Jones Beene <jone...@pacbell.net> wrote: > *From:* Robert Lynn **** > > **Ø **** ** > > **Ø **If you have a few hundred million $ to put into Stirling > development then by all means have a go and see what you can do, but almost > no-one who has actual experience of Stirling engines and their problems > (and I know a fair number) would put their own money into developing them > for automotive LENR. **** > > ** ** > > Of course it makes no sense to use a Stirling for fossil-fuel powered > automotive, given the sunk cost in the ICE - and NONE of these companies > you mention presently believe that LENR can provide low cost heat. So you > are conflating two distinct issues that do not mix well.**** > > ** ** > > Once you get over that hurdle – that LENR is valid, then the Stirling > makes a lot of sense, compared to other alternatives like steam - but not > to be implemented by aerospace companies, whose cost structure is not > competitive with the automotive arena by a wide margin. **** > > ** ** > > No one can disagree with you that the Stirling make little economic sense > to use with fossil fuel, but we can all agree that this fact is irrelevant > to anything related to LENR, other than that it represents an added risk, > when most companies want to avoid risk, and especially when LENR is not > proved.**** > > ** ** > > Even with solar, where the Stirling has not worked out yet –that is due to > greed and mismanagement more than anything else, combined with a massive > drop in PV pricing. Stirling Energy Systems (SES) filed for bankruptcy > after failing to obtain financing for massive projects that were > boondoggles to begin with. This is part of the same Solyndra, SpectraWatt > and Evergreen scams, where billions of taxpayer dollars was wasted by > “entrepreneurs”, most of them former DoE staff - who came out smelling like > a rose. **** > > ** ** > > The absurdly high cost of manufacturing of the SES engines were actually > the crux of the problem that was never adequately addressed by competitive > bidding. They expected DoE to step in bail them out, and for once this did > not happen.**** > > ** ** > > The Stirling technology is valid, and the Chinese will once again seize > our missed opportunity and optimized the Stirling for solar – and maybe for > LENR as well - by producing those same $20,000 reciprocating engines for > less than the $5,000 that should have been our goal to begin with. **** > > ** ** > > All these technical issues are solvable, but you have to desperately want > to solve them; and China is in that position, since they have little oil… > whereas the USA and even GB are only moderately committed, due to having > just the right amount of oil (to maximize incomes of oil barons and > politicians) - and also by having well-placed technology manipulators - who > would love nothing more than to see LENR and a Stirling implementation of > it be delayed as long as possible.**** > > ** ** > > Jones**** > > ** ** >
