Robert, Did you have any info on GE/Siemens working on S-CO2? I am very interested.
Corey On Mon, Feb 27, 2012 at 2:46 AM, Robert Lynn <robert.gulliver.l...@gmail.com > wrote: > That was my initial reaction too. But recuperated transcritical CO2 > Brayton can hit up to about 70-75% of Carnot efficiency (higher at higher > temperatures due to basically fixed temperature difference in > recuperation), and is actually more efficient than a practical Stirling can > manage (Stirling is only about 60-65% of Carnot at very best). > > Assuming 310K cold end (CO2 critical point is 304K) and 524K hot end the > Carnot efficiency would be 41%, and 70% of that would be 29%. So 30% > efficiency is within the realms of possiblity. > > All the big players like Siemens, GE etc are busy developing CO2 power > plant machinery because it is more efficient, more compact, much cheaper > and can withstand higher temperatures without the corrosion issues of steam. > > > On 27 February 2012 04:42, James Bowery <jabow...@gmail.com> wrote: > >> Can't be. Rossi's inlet temperature is 524K. With an outlet temperature >> at 373K (100C) the maximum Carnot efficiency is only 29%. >> >> >> On Sun, Feb 26, 2012 at 4:35 PM, Alan Fletcher <a...@well.com> wrote: >> >>> SST-040 looks a good candidate : 300kW from 1MW >>> >>> http://www.energy.siemens.com/hq/en/power-generation/steam-turbines/sst-040.htm >>> >>> The newly developed predesigned steam turbine SST-040 is a generator >>> drive specially designed for the 75-300 kW power range. This favorably >>> priced turbine features a simple, extremely compact design, short start-up >>> times and a high degree of operational reliability. >>> >>> Application area of the SST-040: >>> >>> * Waste-heat recovery e.g. behind gas engines and biogas engines >>> * Small CHP plants >>> * Decentralized solar facilities >>> >>> Inlet pressure 2 up to 40 bar (a) >>> Inlet temperature dry saturated steam up to 400 °C >>> >>> ----- Original Message ----- >>> > From: "Robert Lynn" <robert.gulliver.l...@gmail.com> >>> > This might be possible with supercritical CO2, though not in sizes >>> > less than about 100kW. Most definitely not steam >>> >>> >> >