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A bus that runs on formic acid
- deleted 9y ago[deleted]
- userbinator 9y ago"The tailpipe emissions are only CO2 and water," explains Mr van Cappellen. "No other harmful gases like nitric oxides, soot or sulphuric oxides are emitted." The same is true of the complete combustion of petrol and other hydrocarbon fuels. I remember the same was said of propane when it became the popular alternative fuel several decades ago.
- roywiggins 9y agoIt sounds like the application of this fuel is meant to be alongside carbon capture, so there's no net emissions at all.
- detaro 9y agoI think the core of the idea is that formic acid is easier to synthesize than other hydrocarbon fuels, while being easier to handle than pure hydrogen. It's also split into hydrogen and CO2 in this process, not burned, which could happen cleaner than practical combustion?
- digi_owl 9y agoThe idea here is that the acid is made from elements already floating around in nature, and thus the exhaust do not introduce more than the production initially removed. This unlike petrochemicals because the exhaust gasses is in addition to what is already out there.
- dthal 9y agoThe CO2 is also an input; it originally comes from the environment, so this is net-zero emissions in the same way that biofuels are. From the article: Although the bus emits CO2, Team Fast argues that the original CO2 used to create the hydrozine is taken from existing sources, such as air or exhaust fumes, so that no additional CO2 is produced - it's a closed carbon cycle in the jargon.
- ams6110 9y agoTrue if combustion occurs in pure oxygen. Combustion of petrol fuels in an automobile tends to produce nitrogen oxides from the nitrogen in the atmosphere. I assume fuel cell reactions don't do this.
- andmarios 9y agoVery interesting work. What they developed essentially is a way to store renewable energy. They take CO2, H2O and electricity from renewable sources to create their fuel. The secret here is the catalyst they developed. The fuel is liquid, thus stored easily. In order to use it they use a reverse chemical process which creates H2 and CO2. The H2 burns with oxygen (and releases part of the stored energy) to produce H2O and thus they end with the elements they used in the first step. If in its currrent capacitiy can be used for transportation, it probably can be used for many other things as well.
- overcast 9y agoSo the catalyst isn't renewable. How much of that do they need? What are the costs, and energy put into that?
- detaro 9y ago> So the catalyst isn't renewable Is it not? Not being used up is kind of the definition of "catalyst" though, so while it might need maintenance/recycling (due to mechanical changes, or contamination) it probably can be reused after processing.
- andmarios 9y agoI didn't make any statement about the catalyst's attributes but I indeed mistakenly attributed its creation to this team. The catalyst was developed in EPFL and is renewable. I believe this is the one: https://www.nature.com/articles/ncomms5017 https://www.nature.com/articles/ncomms5017
- p1mrx 9y agoFormic acid contains 53 g/L of hydrogen[1]. The Mirai has a 500 km range, using 5 kg of hydrogen[2]. So you would need 95 L (116 kg) of formic acid to get the same range. The actual tanks on the Mirai (87.5 kg, 122 L) are physically larger, but weigh less. [1] http://large.stanford.edu/courses/2013/ph240/yoo1/ http://large.stanford.edu/courses/2013/ph240/yoo1/ [2] https://en.wikipedia.org/wiki/Toyota_Mirai#Fuel_economy_and_range https://en.wikipedia.org/wiki/Toyota_Mirai#Fuel_economy_and_...
- bluejekyll 9y agoSeems like a decent tradeoff. The extra weight would reduce the range, but the gained tank space might make that ok?
- twic 9y agoI imagine the formic acid also has safety advantages: it's stored at room pressure rather than under pressure, so the tank can't explode, and if there's a leak, it won't vapourise. On the other hand, it's reasonably nasty stuff, although far from Things I Won't Work With levels of nasty: https://www.cdc.gov/niosh/ipcsneng/neng0485.html https://www.cdc.gov/niosh/ipcsneng/neng0485.html
- jimrandomh 9y agoIt has an energy density of 1.77 kWh/L and 1.22 g/cm^3, or 1.45 kWh/kg (http://pubs.acs.org/doi/pdf/10.1021/acsenergylett.6b00574 http://pubs.acs.org/doi/pdf/10.1021/acsenergylett.6b00574). Compare to gasoline at 12.9 kWh/kg (https://en.wikipedia.org/wiki/Energy_density https://en.wikipedia.org/wiki/Energy_density) and li-ion batteries at 0.1-0.3 kWh/kg (https://en.wikipedia.org/wiki/Lithium-ion_battery https://en.wikipedia.org/wiki/Lithium-ion_battery).
- digi_owl 9y agoHonestly nothing can beat gasoline up front. but here we have something that can match li-ion, but that can be refueled as easily as one refuel a gasoline car. Can be stored for long periods on simple containers. And can be produced from atmospheric gasses.
- jws 9y agoInteresting implications for fixed location energy storage. A palette sized tote of water is about 1000 liters, so 1.45MWh/tote. That is roughly a month of US household electrical consumption. I'm not finding numbers for efficiency of creating the formic acid, and for the catalyst I find notes that the good ones use expensive elements. So I guess when my new lead acid battery bank wears out in 8 years I won't be installing a formic acid system.
- nimish 9y agoNo mention of handling issues around liters of irritating acid...getting stung by ants is bad enough
- alkonaut 9y agoHow strong an acid is this? If it's not extreme then handling shouldn't be much worse than petroleum fuels which are mildly irritating, toxic, and flammable. We have built infrastructure to let people handle those products (rather) safely.
- nimish 9y agoHave you been stung by an ant or stinging nettle? It's not fun.
- alkonaut 9y agoSure, but I can imagine ants that injected gasoline or vinegar (for example) would be unpleasant too - while having those substances on your skin is fine. Formic acid is a relatively weak acid (if I can read wikipedia correctly), much more like acetic acid than sulphuric acid.
- nikdaheratik 9y agoYep, from what I can tell it's about 10x stronger than vinegar at the same concentration, but about 1/7 the strength of citric acid (lemon juice). It's often use in wart treatments so it's not too bad in small concentrations. However, it's flammable and can cause acid burns in the concentrations they're talking about in the article.
- petre 9y agoIt's a weak acid similar to acetic acid (vinegar contains 9% acetic acid) but weaker. https://en.m.wikipedia.org/wiki/Formic_acid#Safety https://en.m.wikipedia.org/wiki/Formic_acid#Safety
- jws 9y agoMaking up a name "Hydrozine" instead of just calling it "formic acid" makes this quite confusing. Maybe it works for marketing.
- kabdib 9y agoYeah, that was a little too subtle. I had to check it a few times before I realized they weren't talking about hydrazine (toxic, probably carcinogenic if it doesn't kill you right away, and definitely not something you want putting around on public roads). If I were their marketing, I'd pick something else, fast. Something a good hamming-distance away from anything requiring special suits for handling, and that doesn't include steps in release protocols like "evacuate nearby towns".
- dkuder 9y agoMixing "hydrozine" with hydrazine gives a hydrazone. "bug juice" seems like a better name.
- FLUX-YOU 9y ago>The fuel, which the team has dubbed hydrozine (not to be confused with hydrazine) /facepalm Why would you cozy up your name next to a horribly carcinogenic rocket fuel? This a nomenclature foot-gun.
- vacri 9y agoSeems reminiscent of the hyper/hypo issue in medical jargon. Not something you want to screw up.
- exabrial 9y agoIsn't formic acid a main ingredient in wasp or bee venom?
- joss82 9y agoFormic comes from the Latin word for ant. It's what ants spray at an intruder when upset. It's also hallucinogenic. Good stuff.
- kabdib 9y ago> It's also hallucinogenic. That's one way to get people to ride the bus more often ... :-) "The driver said my downtown stop was the one with all the candy-canes, but all I see are walruses with briefcases."
- dankohn1 9y agoHighly recommend Ender's Game and the many sequels, where the alien insect species is known as the Formics.
- awjr 9y agoDoesn't this solve the battery storage issue for renewables? I mean you can produce lakes of this stuff and 'burn it' when needed. Strategically could be worth shipping/piping from a high sun/wind/geothermal area. The key is that it is a way to store renewable energy easily and cheaply.
- rini17 9y agoFormic acid freezes at 8°C. Hooray.
- tambourine_man 9y agoInteresting. What's the catalyst made of? I remember they used to require platinum and other expensive elements. Also, using CO2 from factories is nice but eventually we need to get rid of them altogether. I imagine taking CO2 from the atmosphere at its natural concentration should be incredibly inefficient.
- darkmarmot 9y agoI can't imagine the horrible smell... just one angry ant is enough to make me ill. An engine full of the stuff would be a nightmare.