John JACK

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About John JACK

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  1. Stolen — from whom? That energy would be wasted anyway. You can not cover every square inch of Earth in solar cells, and even if you could, there is no way to harvest all the energy. And there is no point in trying — amount if solar radiation is huge but still limited, and most of it is needed for ecology to work. Plants growing and falling are still part of global ecosystem, and solar cells fields are not. Joules spend into branches are stored for our consumption and joules spend into seeds save us joules to plant seeds again. So we still get free energy, and plants steal only from heating bare ground. And the water weeds get is still free — from rain and ground. And in sunny day that thin layer will be scorched. Plants' leaves are green and semi-transparent for a reason. That reason is no process is hundred percent efficient. Leaves need to adsorb only small amount of solar radiation, reflecting or letting through most, to prevent overheat and maintain comfortable temperature. Algae ponds will need to evaporate huge amounts of water (fresh clean water), and still may cook contents to soup in best days. Nope. People already cultivate more area — to feed people. Fields already need windbreaks, or they turn into dustbowl desert in several years. Harvesting windbreaks for energy don't need additional area cultivated. And it actually boosts fields productivity, while taking nothing to maintain. While solid layer of algae requires energy, water, electricity — and land area that must be stolen from fields, forests, meadows. Yep, but that's deep space propulsion. Boosters still need TWR that only chemical (or despised N-word) engines have, even if assisted by mass driver. Though most human power needs still can be satisfied with wired or canned electricity. Well, good luck lugging your microwave (with a hundred mile spool of cable) to a camping trip. I hope there still be woods and fields to trip to. Public transport is not a solution for everything. Walking half-hour to a trolley stop may be healthy but is not very time effective. Just like two or three transfers on one leg of a daily journey.
  2. Well, electricity replacing even portable heating devices (where burning hydrocarnons is both cheapest and more effective way) is surely science fiction. Maybe even retrofuturism, because to that time we'll already use non-electrical power everywhere. Not exactly. In urban environment cars often are parked at public parking area away from owner's home. So that places must be equipped with (paid) charging outlets where none was before. Also electric cars draw ludicrous amounts of current — Tesla needs at least 48 amps, while almost every household has just 25 amp main fuse. Tesla still has 400 kg of batteries, and while mass can be lowered, power capacity will only increase. Parking areas and charge stations will need to be connected by pretty thick cables, and if everyone drives an electric car, all city power grid will have to be doubled or tripled. That will happen eventually, but sudden change to electric transport will demand for expensive infrastructure overhaul. But liquid or liquefied fuel is compact, stores well and can be transported in simple tanks. I agree that light hydrocarbons are simple to synthesise, and they are easier to distribute to every car. And you cannot power a rocket or a jet by electricity!
  3. Basically, if you read something and think "that mulch doesn't make any sense", that means it's really is mulch that doesn't make any sense?
  4. They spend free energy for whatever. Bigger plants adsorb more atmospheric CO2 and bigger plants capture more sunlight. And bigger plants need less land area for same biomass production. Algae pools have no height and almost no surface area, so you need to spend our energy to deliver CO2 at least. We spend our energy only to plant them (for a first time), and to harvest them. And weeds don't need much watering or fertilising. Lazy, cheap and effective is good. Big grass plants don't even need their own fields — they can be grown between and around, as windbreaks. Each winter you can cut every other strip, and leave next to keep snow. That's one way. I looked up Fischer-Tropsch and it really gives a mix of different alkanes, good as fuel. Though it's comparable to lighter oil fractions, for chemical use product needs more processing. And you totally can use plant matter for this — gasify it with some water, run on catalyst, separate and reuse water. In return you get less energy than by burning hay outright, but yield nice liquid. Yes, because fossil oil is cheapest and most common raw material. That doesn't mean nothing can be done without it. It will take more power, but power is getting cheaper and less dependant on fossil hydrocarbons. You listed methods of CO2 production. To capture carbon you need to grow biomass, not to burn it. Methods to capture CO2 from air (where it matters) are physical (partial liquefaction), biological (grass fields, algae pools) and chemical (alkaline and other scrubbers). Power is already dirt cheap. Will be even more cheaper if people wouldn't whine about clean and safe nuclear plants and did not insist to continue burning radiation-death spewing coal stations and useless wind turbines. The trouble is that cheap power is wire delivered, use it or lose it. And ways to store power are not cheap. Batteries have high dead weight and low capacity, safely(ish) stored hydrogen is even worse. Also fusion reactors must be big to be effective (as in one station for a continent big), so transmission cost will be higher too.
  5. About default pump level. May I suggest to hard set it from 0 (lowest) to 8 (middle)? That will allow to leave most tanks at default, and be able to alter it both uphill and downhill only for chosen tanks. Now you make, for example, a refuelling station with level 8 and pumps on. Tankers have level 10 on transport tanks, and craft to be fuelled have 6. Everything set manually, of course. Than you launch a tanker, have spare fuel in upper stage, and decide to bring it along. You dock. And all the fuel in station is sucked to that stage. Because booster tanks were left with default level 0 due to lazy and dropped anyway.
  6. Is it? As far as I remember, stock contract system still ask to launch a new station every time. But there is a mod for it: http://forum.kerbalspaceprogram.com/index.php?/topic/102390-10511x-contract-pack-bases-and-stations-3211-290416-formerly-kerbin-space-station/
  7. It would be fossil fuel all again. Whole point of going carbon neutral is taking carbon from atmosphere, where it matters. Mining everything (except short lived plants) for carbon will add to global warming, just as oil and coal. To help we need go backwards — grab carbon from air, solidify and bury it. And that's best done again with plants. Everybody loves oil not because oil is that great. Everybody loves oil because for every unit of energy spent in extracting and refining it, they get TEN units of energy back. That gives enough spare energy to support people and institutions not busy in making energy. Like workers, engineers, scientists, artists, game developers and so on. Otherwise they would have to mine coal or plow fields or scavenge fruits and seeds just to support themselves, not do anything nice they do now. Also oil is great raw material for chemistry. But to make lubricants, plastics, food and everything else it's first split to components. And that components may be too harvested from plants or synthesised more or less directly. Actually, to make crude petroleum from hydrogen and carbon you'll have to synthesise it's components and mix them. Synthetic oil will absolutely not return that much spare energy. Actually it will return less than was spent in it's production. So it may be profitabe only when produced by using even cheaper energy — nuclear or better fusion. Otherwise synthetic fuel is just a wartime erzatz — you spend expensive coal energy to power your war machines to get sources of cheap energy. Because tanks (or rockets) do not run well on wood and coal. Switching over global fleet of cars isn't that hard. Modern cars are already made to serve five, maybe ten years, and than be replaced. If new generation of cars will use gas tanks of fuel cells, people would buy them. IF they are better and cheaper, of course. Electric cars are still much more expensive than LF ones, and cheap recharge is ruined by low mileage. Through 20 century and still now, overall inefficiency of ICE engine is offset by cheap, handy and very energy dense liquid fuel. If it became not so cheap, people will switch to other fuels. Like they are massively switching existing cars to methane and LPG right now. It's simple and in a long run it's cheaper. Synthetic methane and propane also would be much cheaper than synthetic petrol. There already is infrastructure for gas stations and car manufacturers can modify design for gas tanks. tl;dr: people need not synthetic petroleum, people need cheap energy. Any form is good — till it's cheap.
  8. Wood gas and steam are (or at least were) viable alternatives to synthetic petrol, so they should be mentioned here. But I see you point. There are weeds in most truest deserts. Iconic dunes make not all deserts, they don't even make most. And desert sand is a very fertile soil — if you add water and somehow fix it against wind until plants grow decent roots. Some plants' roots reach very deep, tens of meters, so watering is necessary only initially too. And best of all, after several years plants turn sand to a soil, and desert is not a desert anymore. Algae are not good at all. Ponds need place, not some wasteland but good flat ground, where you can build other, more profitable stuff. Ponds need fresh clean water, that is scarce and precious. And pond need constant maintenance, when plants grow by themselves. Algae tanks may be better in space, but in space you don't need much petrol anyway. Methane is bulky, but it's cheap, twice cheaper than petrol or diesel. It's common fuel for buses, that need to run constantly. Lower mileage and bulk of pressure cylinders (150 bar, industry standard for compressed gases) is not a concern, cleaner exhaust and longer engine life is a bonus. Propane and butane, with other neighbour compounds, like in your gas stove cylinder, are even better. They have pressure lower than 16 bar, as low as 2 bar for pure butane so can be stored in a tin cans, and are only slightly less dense than gasoline. Minor drawback is that they do not evaporate well in cold weather, but it's not a concern for most climates and is solved with a simple preheater. Propane-butane mix is already commonly used in passenger cars and small trucks, with minimal modification of fuel system. It's less cheap than methane, but simpler to use, gives good mileage, and pays off on a long run. Bonuses as above. Methane, propane and butane are simpler to make than petrol-like liquids, and only slightly less simple to use.
  9. Just like I said. Plenty of already existing ICE cars — check. Lack of petrol — check. Cheap skilled workforce to make and service generators — check. To the beginning of WWII petrol cars already phased out steam cars, that were never popular in first place. So tinkering with tubes and barrels and breaking some furniture was the only choice for non-essential people. Notice that no one bothered to convert ICE ships and locomotives to wood gas, but coal fired steamers hauled cargo on sea and on rail well after the war. Ah, it said that someone did bothered. I still suppose that were one-off tests, presumably of Teuton genius origin. They even did tanks on a wood gas (for training).
  10. Nope yourself. Wood gas generation process does yield only 1/3 of fuel energy, that's right. But a steam boiler (slightly more complex than a tin can on a candle) has efficiency of 80-90%. That's almost all energy of burning fuel goes to the energy of superheated steam. The next step is an engine itself. Here ICE has efficiency of ~30% (in best case) and steam — of 5-10%, though steam turbines are much better, 40-50%. But. Wood gas is a poor fuel for an ICE, because it's not only hot and dirty, but consists mostly of nitrogen (generator intakes air, and only oxygen reacts with wood). Engine efficiency on a wood gas is several times worse than on a proper fuel. So engine efficiency is pretty much same. Altogether wood gas engine is both less efficient than a good steam engine, AND needs better fuel. Gas generator cannot use waste, steam boiler can. The only reason that people use wood gas and not steam is sloth cost. ICE engines are mass produced for ages, and are dirt cheap anywhere. Gas generator is just a barrel with some tubes. And work cost nothing is you can not even afford petrol. Steam engines are not mass produced for ages, and never actually were. Thought you can make a steam engine, good efficient boiler is not just a barrel with some tubes, but a pressure vessel with high temperature. There are no cheap boilers, there are good boilers and there are bombs. And if you can afford a good boiler — you are rich and can afford petrol, steam is only a hobby. Right. But plants are not even using a small percent of available anyway. For example miscantus or hogweed grow to several metres high in a single year. There are plenty of CO2 in air and solar energy for more, they use just a little percent of available. And there are deserts on Earth, where plants can grow great, but doesn't want to. Algae basins, on the contrary, have a drawback of low surface area, you need to bubble air (with CO2) artificially. Also replenish water, watch for contamination and whatever. Weeds grow by themselves, and do it on any unused land, just plant seeds in spring and harvest biomass in winter. You don't need actual petroleum to carry or store energy. Hydrogen and methane are simpler (need less energy) to produce, and work just fine, and are even better for rockets. Only reason to bother with making synthetic petrol is presence of Otto-engine cars and only solid fuels and need to make them work together.
  11. Actually, there's no such thing as "LPG engine". Every ICE can use gas a fuel, with minimal modification and tweaking. Propane and methane are even better for engine life because they make less tar, soot and acids. Wood gas is dirty, even with huge filters ash clogs and wears engine. And it's hot, so underpowered engine also overheats easily. But gas generators are slightly more than a barrels with some tubes, and are not expensive even in giant quantities. What is expensive in wood gas, that's amount of work to prepare fuel, load it, starting fire, cleaning ashes, managing reaction speed and generally maintaining everything. Even when wood gas is an only choice, it's used mostly for trucks and buses, with dedicated firemen. Only rare enthusiasts may use it for a personal car. It's more efficient than just let your petrol-engine truck to rot. Wood waste is more effective burned in a steam boiler. Wood gas generators just don't generate wood gas if fed with trash and rubbish. Yep. That's why we need engineered breeds. With better efficiency to take less area, resistance to pests and diseases, able to grow on poor soil. To plant on wastelands.
  12. Hydrogen is a bad fuel for everything except rockets and fuel cells. And even those work on methane pretty well, and methane is a joy to handle compared to hydrogen. Methane and other hydrocarbons are already produced by lifeforms, so no need to inventing new genes, tweaking existing may be enough. EROI of synthetic and bio fuels is pretty bad. Oil is so energy rich and ease to process that any other fuel is much more expensive. Except nuclear, but it's not a subject here. People use surrogates only when they have no access to fossil fuels, or want to be "green". And hydrogen is not even a power source, it's a way to store power. It competes not with petrol, but with batteries.
  13. Arguably best plants for energy source now are various grass like miscanthus. It grows pretty much anywhere and gives huge amount of biomass in just one-two years. Using stems and leaves instead of seeds guarantee enough produce even despite pests or weather. But cellulose isn't most convenient stuff if you want not just burn it outright, sugar or oils are better, and there is much to be improved. Biofuel is not necessary yet — fossil fuels are cheap, plentiful and more effective, so it's not used widely. Only some tropical countries use it because it's cheap there. Nah, wood gas is nowhere near efficient. Engine give just third of it's power on it, and generator need to be restocked with dozens of kilos of wood every couple of hours. And you cannot use just some waste, gas generators need high quality dry wood, cut to cubes of certain size. Some generators may run on pellets, made of pressed ships, but pellet making consumes power and labour too. So ­— combination of good cheap workforce and of total lack of other fuels is absolutely must to use wood gas generators. And it happens only in wartime or similar conditions. You need postapocalyptic setting to justify worldwide wood gas power. It's effective enough to burn wood and other plant matter like peat in thermal power station furnace, though you need much bigger volumes than coal. But there are no effective portable engines for it. Even running steamers on wood is only for very rich or very poor people.
  14. And far more very cheap but motivated labour force. And far more forests, that do not grow again overnight. Wood gas is only for really desperate, when you need to operate at least something no matter the cost. Yep. Right now humans have to process food to fuel because there are millennia of selection of edible plants, but there was no selection of combustible plants. We need bioengineering to make fuel without wasting (much) food for it.
  15. Right. But it's at least a renewable source that is available almost everywhere. And diesel engines can work on (processed) vegetable oils with minimal modification, like Otto engines on spirits and methane. Biology is absolutely not efficient as chemistry, but it's cheap, self-sustaining and self-reproducing. Plant it, wait, harvest, spend a little energy on processing, repeat. You need just sun and enough place for fields. And with SCIENCE!!! it can be made much more effective. Even better, you can burn other parts of a plant that are not sugar. That returns most of CO2 to atmosphere, but still not produce more.