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550 kg of hydrogen is about 550 gge. Conventional tankers carry thousands of gallons per load. Any H2 scheme which uses compressed-gas tankers is going to have many times the road traffic of our current system, with all the traffic and collision problems that implies. Electricity is just so much better in almost all ways.
As I recall, the TIGERS system used a switched-reluctance generator to get around problems with permanent magnets.
Anyone with a PHEV or BEV is already fueling at home, and has no issues with leakage or explosion hazards. Remember the Phill home-fueling pump for CNG cars? Apparently there were issues with it (moisture or what, I never learned). Just watch for the same sort of troubles with these small hydrogen generators (aside from the high expense).
To get improved economy out of a smaller engine, it would have to take a page out of the book of turbodiesels. The key feature of the turbodiesel is the recycling of exhaust energy to the crankshaft via the turbocharger. When the intake manifold pressure is higher than the exhaust BP, the pressure on the piston during the intake stroke can be greater than that on the exhaust stroke and the engine reaps pumping gains instead of pumping losses. It should be possible to turbocharge an Atkinson-cycle engine and achieve a similar cycle. Reducing the geometric compression reduces the compression work, but the expansion work will be about the same if the air charge is unchanged. Also, a hybrid is ideally suited for TIGERS, reclaiming any excess exhaust energy via the HV electrical system instead of using a waste gate. Is it worth the expense? I don't know. What I can say is that I've driven a 2-liter turbodiesel cranking out 95 horsepower, and a 2-liter Atkinson probably doing less than that... and the turbodiesel does the job much more quietly and likely more efficiently as well.
My Fusion Energi eked out 4377 miles between the last two fill-ups, averaging over 350 MPG.
Blast-furnace gas isn't vented, it's burned. Robert Rapier keeps bringing up the issue that LanzaTech refuses to talk about: just what is the ethanol fraction of their fermentation product, which determines how much energy is required to distill it? The "bottoms" must be heated to boiling to get the lost fraction of EtOH down to an acceptable value. If the starting fraction of EtOH is 2%, an EtOH fraction in the bottoms of 0.5% represents 25% of the input compared to 5% if the starting fraction is 10%. You also need 5 times as much process heat for the distillation. The best use of blast-furnace gas for vehicle propulsion is probably combustion in a combined-cycle power plant to generate electricity for EVs.
Funny, I have been intermittently working on a spreadsheet to analyze the heat-transfer issues of something very similar to this. Glad to see that someone made it real already. The major issue I can see is solubility of the gas in the liquid phase, which results in leakage through the water as it's bled back to the inlet pressure. With air this will not be a big problem using water, but you couldn't compress e.g. CO2 using water. OTOH, as a way to scrub air of CO2 this would be great.
just think about heating a combustion engine from 0 degrees C to a couple of hundred degree C, how much heat energy that takes and how long it will take to do that? The answer of course is that they manage just fine The difference being that the ICE can provide a large fraction of rated output power even when its coolant and lubricating oil are well below 0°C. The PEMFC cannot. If the FC stack is heated in sections, the battery could pre-heat one to starting temperature and then the waste heat from that one could thaw the rest in turn as they start providing power to the vehicle. It would be interesting to say the least. If the FC can't use reformed liquid fuel, there's going to be a chicken/egg problem. Hydrogen's going to be hard to find for some time.
Ruthenium is also one of the catalysts in the one-pot cellulose-to-hexane process. Long ruthenium?
The Antelope Valley has quite a bit of sun. The BYD can only charge off-line, typically at night when solar power is not available. Something like the Busbaar system, with buffering such as flywheels, would be able get solar power to an electric bus in near-real time and requiring a much smaller battery.
Hydrothermal processes are not pyrolysis. The temperatures in this process are not even sufficient for torrefaction (250-275°C), let alone pyrolysis. The nomenclature issue aside, if the catalysts are recycled easily/cheaply enough to make this work, there's a lot of feedstock out there just waiting to be turned into fuels or chemicals. A biomass-based source of polymers and such allows the products to actually sequester carbon. Imagine landfills as climate protection schemes!
by 2017 Tesla will have superchargers everywhere in the world. What will GM, VW and Nissan have to support their long-range BEVs? Tesla opened the patents on their charging systems and protocols. GM, VW and Nissan have no barriers to building vehicles that can also use the Supercharger network.
Oh, sure, you can do it... but how much does it cost, and what sort of losses are there? When does it make sense to use a Busbaar instead?
OT, but Bobby... much of what you think you know is actually lies.
The proper way to measure heat output isn't with non-contact thermometry. It's with calorimeters. You capture the heat in a fluid and measure the ΔT for a known dM/dt. Also, you don't maintain electric power to control device temperature. If it's generating heat, you insulate it to reduce the heat loss to the level which holds the correct temperature. That allows the power to be disconnected... and also prevents tricks like measuring power via a differential-mode meter while adding extra power via a common-mode voltage. Those criticisms have been made before. Since the experimental technique was not changed to address them, it can be assumed that this is a trick.
No, just pointing out where you got too deep in the ridiculosity.
What's the cost of DOUBLING the raw feedstock consumption for the same energy delivery at the wheels? As I said, I can see GTL for stranded gas. But for powering cars and trucks, piped-in gas (either compressed or liquefied) is far cheaper and vastly more efficient, both in $/gge and in carbon emissions per GJ delivered.
The US Navy could turn this into a profit center, renting out the swarm boats to protect shipping from pirates.
Since carbohydrate is only 40% carbon by mass [(CH2O)n] if you could get 1000 lb of biochar out of a ton you'd get almost nothing else with carbon in it.
Converting natural gas to any other molecule is wasteful and unwelcome? Have you looked at the chemical efficiency of GTL processes? The higher numbers appear to be around 50%. The carbon efficiency can be 80%, but even if the process carbon is sequestered you are still emitting 80% of the carbon at the tailpipe to get just 50% of the energy. When you have engines that can burn natural gas directly with only minor penalties for compression or liquefaction, GTL with non-stranded gas is an environmental crime.
This article begs the question of where the process energy comes from. The PDF at the link states that the process is carbon-negative, but no mass, carbon or energy balances are given. A 10x reduction in capex is good. A product with a strongly positive EROEI that's profitable without subsidies is better.
There would have to be a lot of other feedstock, yup. This comes back to thermal efficiency. Methanol or M85 can be burned in much higher-compression engines than conventional gasoline, with much higher specific power (thus smaller size and lower losses). Converting methanol to gasoline should be regarded as going backwards. For that matter, with the Westport/Delphi injector system, converting natural gas to any other molecule should be regarded as wasteful and unwelcome.
Let's see... 1.75 million tons MeOH @ 22.7 MJ/kg HHV = 3.97e16 J 8 million bbl gasoline @ 42 gal/bbl @ 3.7854 l/gal @ ρ=0.751 = 955,000 tons gasoline. 955,000 tons gasoline @ 43.7 MJ/kg = 4.18e16 J Something doesn't add up here.
We don't need molten-salt breeders any time soon. Terrestrial Energy (Dr. David LeBlanc) and his team noted that trying to certify a brand-new fuel and deal with the proliferation issues of a breeder made it far too costly for a first product. They're aiming at the rough range of 30-300 MW(th) and trying to undercut FFs for process heat by making the unit cheap, rugged and foolproof. If we're lucky, we'll be getting our MSRs from Canada. If we're unlucky, we'll be getting them from China.
Must agree with Roger. Unless the refrigerant is something cheap and environmentally harmless in the quantities required (like isobutane or CO2), leakage past seals is probably a bigger deal than a bit of energy savings. Just getting rid of the need for regular service will be a big advantage that this scheme foregoes.