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I'm assuming the purpose of developing a more efficient engine is to reduce emissions and thus "saving the planet"? That may seem commendable, but from what I h

• dredmorbius 11y ago
  There are advantages and disadvantages to internal combustion engines. Compared to external combustion engines (steam engines), ICEs have much quicker start-up and response times. Steam engines require building up a head of steam, and actually exhaust the working fluid (water) over time, which is why steam railroads had water towers every so often. ICEs have been improved over more than 130 years, and scale from a few CCs of displacement to many cubic meters -- the smallest ICEs could fit in the palm of your hand, you could stand in the largest and not reach the sides or top of the cylinder. Liquid hydrocarbon fuels are exceptionally energy dense by both weight and volume. This makes certain classes of use very difficult to substitute for: commercial passenger and freight aircraft, overland truck transport, and powered marine shipping really have few tractable alternatives. Aircraft would all but disappear without liquid hydrocarbons (gasoline for piston engines, kerosene for gas turbines), trucks would probably be replaced with electrified rail, and shipping would return to wind power. Optimists might suggest nuclear marine powerplants, but I find that unlikely; ships are lost at far higher rates than is commonly realised: about 200 every decade, and existing trials of both military and nonmilitary nuclear marine power have proven it expensive and nonviable for all but the most demanding instances -- aircraft carriers and submarines. They're also quite stable in storage (proved over hundreds of millions of years), relatively safe to handle (no respiration or exceptional contact protection required), and their combustion products are mostly benign: CO2 (I'll get to this) and H20 with scant quantities of carbon monoxide, sulfer and nitrogen oxides, and other contaminants or partial combustion products, all of which can be greatly mitigated with combustion and exhaust controls and treatment. The CO2 exhausted isn't a problem in itself but for the, um, slight problem that in the past 200 or so years humans have returned to the biosphere carbon sequestered over several hundreds of millions of years. Which turns out to be a rather considerable problem. But it's only a problem where what you're burning are fossil fuels. There exist several options, though all much more expensive and/or constrained than present fossil fuels, for creating synthetic hydrocarbon-based liquid fuels. These also have challenges. Biofuels are intractable at scale given natural limits on plant production: what's called "HANNP" -- the human appropriation of net primary production -- or the photosynthetic ceiling. There's only so much plant growth which occurs and humans already consume much of it (40%, biofuel replacement of fossil fuels would consume another 20%, see Jeffrey S. Duke's "Burning Buried Sunshine" (2003), PDF available online, for more on this. Another prospect: sequestering carbon from the biosphere, and combining it with hydrogen, electrolised from water. The US Navy and national energy labs (especially Brookhaven), as well as M.I.T., have researched this for the past 50 years. It's proven expensive and hasn't been scaled past very low production (a few litres), but does work. It raises costs of fuel from one unit of input energy per 20-40 units made available to two units per one provided -- that's a 40-80x increase in the real cost of fuel. Not cheap, but it might still be our best option.
  • Torkel 11y ago
    Interesting, and I fully agree that sequestration would be a solution. I root for electric propulsion and solar power (go Elon!). But I support all efforts in this fight. I will read the references you gave. Edit: "Burning Buried Sunshine" is a great read! 86 m3 of ancient biomass for 1 gallon of fuel..
    • dredmorbius 11y ago
      BBS is good. I'd been of the inclination that biofuels were viable prior to that, it pretty much single-handedly changed my mind. I really like that it gives a detailed breakdown of how fossil fuels come to be and their various and relative formation efficiencies. Carbon sequestration from seawater is a rather different animal from most CCS discussions. Though, in the world of strange bedfellows, it turns out that various coal industry organisations follow this information pretty closely and have some of the more complete compilations of research. Just ... beware biases.
  • Retric 11y ago
    Hybrid cars remove most advantages to IC engines as start-up and response times can be made irrelevant. Further, cars generally only need a small fraction of engine max power hybrids also allow for heavy engines relative to HP as most cars can maintain highway speeds with less than 40HP. PS: As to fuel vs. energy costs. The vast majority of gas's costs has nothing to do with direct energy costs. Oil is already vastly more expensive than competing fuels so even a 2>1 energy loss could end up less expensive than current production methods.
    • dredmorbius 11y ago
      Hybrids do bring much of the best of ICE and electric traction to bear. At the cost of increased complexity and weight.
      • CarVac 11y ago
        No, battery/fuel cell hybrids. No additional complexity, just additional weight.
• dredmorbius 11y ago
  As for downvotes: best not to talk about them. I'd had a comment downvoted and flagged recently, perhaps understanably, though the follow-on discussion made pretty clear that I'd identified a pretty salient point. Upshot: HN is no less immune to voting what it wants to see over what's true or not. I may even be subject to that myself, though I prefer to see my votes as aiming for at the very least a deeper truth and validity. I wasn't among your critics.
  • Torkel 11y ago
    Thank you for this comment! I think your advice is correct: better not talk about it, and move on. Btw I am now in a weird situation - should I remove my edited comment or not. But I'll let it sit there, this thread makes no sense without it :)
    • kbenson 11y ago
      I think it's always more honest to either append, or modify and summarize the changes if shortly after comment creation. If it's immediately after and it's just typo/grammar fixes sometimes I'll just modify without a note. My thinking is that you can't have an honest discussion if people can't count on their replies applying to the parent after the fact, and if I've screwed up enough that I want something off the record, I really should have thought more before writing it, so leaving it and the sting of it's continual viewing is a good reminder for the future.
  • Grishnakh 11y ago
    >I downvoted you because your comment doesn't contribute anything useful to the discussion Sorry to go off-topic, but how do you down-vote people? I've looked through the FAQs and everything and can't find anything about it. I only have the ability to up-vote.
    • dredmorbius 11y ago
      Once you accrue enough karma (~1,000 points IIRC, though that may vary) you'll get a downvote button. It's conveniently placed close enough to the upvote button that on mobile, any moderation action is essentially a 50-50 probability of either....
• acchow 11y ago
  The futility of efficiency gains is touched upon in Bill and Melinda's annual letter this year https://www.gatesnotes.com/2016-Annual-Letter https://www.gatesnotes.com/2016-Annual-Letter He talks about the Energy Equation and declares green energy as the only solution to our carbon emissions.
  • bjt 11y ago
    I wasn't convinced by this bit: > When I first heard this I was surprised. Can’t we just aim to cut carbon emissions in half? I asked many scientists. But they all agreed that wouldn’t be enough. The problem is that CO2 lingers in the atmosphere for decades. Even if we halted carbon emissions tomorrow, the temperature would still rise because of the carbon that’s already been released. No, we need to get all the way down to zero. So if we can only reduce them by 99%, we shouldn't even bother? It seems to me that the closer we get to zero, the more expensive the next 1% will be. At some point, it's not worth the cost to keep going, and we'd be better off looking for ways to remove some of the CO2 that's in the atmosphere instead of just reducing how much we're pumping in. His equation notably omits that possibility.
    • Silfen 11y ago
      There is likely an efficient (in the economic sense of the word) level of CO2 emissions, but I doubt that anyone knows what it is. It's very difficult to price. However, I do agree with you that it's probably not zero. The good news is that we have a proven carbon capture technology. Grow new forests.
      • Nutmog 11y ago
        Forests aren't sustainable unless you're also logging them and storing the wood permanently somewhere. They also consume valuable fertile land so it's not necessarily a worthwhile method. Perhaps in some post-oil economy they would become economical.
    • snowwrestler 11y ago
      I think they're really talking about opportunity costs. Dollars spent on making oil-burning engines more efficient are dollars not spent on developing technologies to replace oil-burning engines, and replace is really what we need.
• Umn44 11y ago
  Hacker news is filled with libertarian/hyper capitalist/anti-global warming types. It comes with the tech head territory, tragically many gifted at tech are shit at reasoning in other areas and are prone to bad politics and conspiracy theories.
• sydneysider 11y ago
  I just want my car to go fast Edit: Whoever is down voting this needs to go outside more often
• ghusbands 11y ago
  On the downvotes, I assume it's because your point is not at all relevant to the article itself or the technology it discuesses. It could easily be copy-pasted to most any article about combustion engines. Technological improvement can be useful enough even if it doesn't "save the planet". Hacker News comments are for discussion of the article content, rather than being a soapbox for your views and blogposts.
• akamaka 11y ago
  I downvoted you because your comment doesn't contribute anything useful to the discussion. Barring some kind of technological silver bullet, "saving the planet" is ultimately a problem of politics and economics. The next problem, of how we can maintain our lifestyle without breaking the emission limits that we set, is what inventions like this one help with. I expect that piston engines will continue to have some applications for as long as I'm alive, so improving them is a good thing.
  • Torkel 11y ago
    I would add technology to your list of things we need to save this planet. And I'd say it's useful to know that making things that burn fossil fuel more efficient is not a viable solution to the problem of global warming. We are now beginning to have good products on the market that are sustainable: electric and solar. Making internal combustion engines more efficient seems a dead end. Or worse - making them more efficient may delay the move to what is actually sustainable. Side note: I regret adding my comment about downvotes. But I will leave it to preserve sense of thread and to remind me not to go there again.
    • akamaka 11y ago
      I didn't have time to elaborate, but I chose not to mention technology on purpose. Unless some inconceivable technological leap happens which makes energy cheaper than $15 oil or coal, technology won't be enough to save the planet. Right now, if one country limits the amount of oil it uses, that just makes oil cheaper for another country which hasn't set limits. 50 years from now, Saudi Arabia could be still burning its last drops of oil to produce electricity, while the rest of the world has moved on to. So yes, you're correct that improving internal combustions engines might not help at all, but that seems to be true of any other technology, too. The only thing that will save out planet is our ability to organize ourselves globally to drastically cut emissions. Side note: don't take the downvotes here personally. HN is a place where quality discussions happen, and a lot of folks would prefer to simply downvote something they don't agree with rather than clutter up the whole thread with responses. :)
• aaron695 11y ago
  You been downvoted because you've said nothing on topic or substance and moved the conservation to a whole new pet political topic you seem to have. Nothing in the article talks about the environment > the purpose of developing a more efficient engine is to reduce emission Generally saving money is why. And as hackers we love making things more efficient. Plus as scientist we love new discoveries, cause who knows where they'll go. Why couldn't this work on a hydrogen or future engine X? Perhaps it won't but scientists discover cause we can.
• ssmoot 11y ago
  Can you produce a car without oil? Especially one containing a large battery pack? Last guess I read put it around 350 barrels for a family sedan. I don't know how much of that is plastics, smelting, and other materials and how much is energy requirements though (and to be fair, I have no idea how close or not that number actually is to the true cost). But given that it takes some amount of oil at least, doesn't that invalidate the argument against increasing efficiency? Because you could call building any sort of car, even a Model S, a loosing battle then. Another thing to think of: if you don't have access to a wall plug, and want to provide an air conditioned environment in a vehicle, there's no alternative to oil AFAIK for anything smaller than an aircraft carrier. Diesel Generators are the only option for air conditioning on Sailing Yachts for example. Nothing else has enough energy density and you can't fit enough renewable (solar, wind, hydro) power to keep up with the amps air conditioning will pull out of it. I know that particular example is very niche. It's just an interest of mine and I'm hopeful we'll see some sort of game changer in the next decade or two.
  • snowwrestler 11y ago
    It is possible to use very little oil for the energy of manufacturing. Most manufacturing processes require electricity, and it's possible to general electricity without oil. In fact, in the U.S. most electricity is generated from sources other than oil. Unfortunately, a lot of it comes from coal, which is worse than oil in almost every environmental aspect. But theoretically the electricity could all come from solar, wind, hydro, and nuclear. Cars have of lot of plastic in them, and oil is the main feedstock for the manufacture of plastic. But that's not really bad in terms of global warming, as a lot of the carbon remains locked up in the plastic (as opposed to burning oil). The final piece of the puzzle is transportation--cars are not built all in one place, the subassemblies might be manufactured all over, and then come together for final assembly via rail, boat, truck, even airplane. Each of those burns oil, so that's a big part of the oil footprint.
    • seanp2k2 11y ago
      Specifically on electric cars and hybrids, mining, refining, and processing the elements in the batteries is pretty nasty business, as is the recycling / disposal of them once they're flat. There are tons of EVs and hybrids out there, and I see this becoming a huge e-waste problem in the near future. Note that Tesla is/was doing something to make the part after they're discarded less bad: https://www.teslamotors.com/blog/mythbusters-part-3-recycling-our-non-toxic-battery-packs https://www.teslamotors.com/blog/mythbusters-part-3-recyclin...
• tarikjn 11y ago
  Most people seem uninformed about this, but there are methods to produce clean oil (short-term carbon-neutral), such as green crude production from algae. Although large-scale production is not there. From that perspective, there is nothing inherently polluting about a combustion engine, in fact gasoline is an excellent chemical store of energy, and in that context possibly cleaner than current batteries. Either way this is great news.
• geniium 11y ago
  You wrote very well what I have in mind. I think the direction they are taking is not the right one. One step further, I suspect the oil lobby pays for this kind of studies. Maybe it will have other usages than car, but I think that's the vast majority of them we are talking about here. Electric is today's way to go.
• raverbashing 11y ago
  > that an increase in efficiency is fighting the wrong battle No, it is not Hybrids will still exist. ICE powered engines will still exist
• jo909 11y ago
  There are biofuels that (for a while at least) have better energy density than batteries. There are applications for internal combustion engines where practical alternatives are not even on the horizon, big ocean freighters for example. It's very narrow minded to dismiss this as "wasted effort", just because it's not part of the endgame vision where no fuel is burned for any reason ever. There are many steps between the status quo and that idealized scenario, and any improvement in efficiency is always a good thing.