In Wikipage “Water-fuelled car” is hoaxes of using water as fuel. But water can indeed be used as fuel. In that page is mentioned carbide lamp. It uses calcium carbide and water as fuel and makes acetylene. Acetylene can be used as additive to diesel fuel or as fuel itself in acetylene engines (Douglas Self netpages: “Acetylene engines” and “The unusual internal combustion engine pages”). So if ship or aircraft uses calcium carbide as fuel and takes water from ocean or air (using atmospheric water generator or other way to condensate water from air humidity) it carries less fuel than using only jet fuel or aircraft gasoline / diesel fuel. Acetylene is dangerous, so water injection, fuel-water emulsion or spraying water to air intakes is needed to tame down acetylene s explosive behaviour. Water turns to steam when acetylenen explodes in engine cylinder or in jet turbofan, steam makes engine more powerful and fiuel efficient, and dampers high burning temperature and overpressure from ignition. Also other fuels with water can be used like ALICE rocket fuel (aluminum powder with water) that is also enviromental friendly. Fuel savings are very huge because water is free from ocean or in air, and it can be used also as coolant in cylinder to protect engine and boost power when it turns to steam. If aircraft takes water from air and uses it as “fuel” it not only saves fuel price but as increased cargo also when less fuel needs to be carried in plane itself. Aircraft diesel engines are already in use, and efficient multi-fuel gasoline and diesel aircraft engines have been made. SMA diesel engine demonstrator is 0,62 litres 1 cylinder 135 hp, 48 cylinder H-engine (two two 24 cylinder boxer engines in side by side) is 6500 hp, with turbo compund mode that is 8500 hp, with turbo compund + turbosteamer mode about 10 000hp, with additional turboprop “afterburner” in turbo compund section about 15 000hp, enough to replace turbofan in jetliner aircraft if 6-8 such engines are used to replace one turbofan in wing). If those internal combustion engines or jet engines use calcium carbide or aluminum together with water they have large fuel savings, and they can use water as cooler in air intake and combustion tamer also, increasing fuel efficiency even further and additional water makes engines that are otherwise unsafe like acetylene or aluminum-water ALICE reaction safer when added to combustion where additional water turns to steam and takes heat away. As for ships or smaller marine engines, they can use seawater as “fuel” filtered and distillated. Diesel engines can use up to 30-35% water as “fuel” in fuel-water emulsion mixture or sprayed in cylinders and with additives in diesel fuel up to 40% can be water content. Fuel efficiency increases up to 19 % according to BMW (5% more power and 13% less fuel, so 1,05X1,13 = 19 % improvement). Using turbosteamer (BMW) increases efficiency for another 15%, so 34% less diesel hydrocarbon / biofuel can diesel engine use when using “water as fuel”. Marine and aircraft diesel engines benefit from this. Not only regular diesel fuel, but other ways increase water content in diesel fuel can be used. Water-methanol injection and nitrous oxide injection are used in diesel engine to boost power. When additional water in combustion lowers power in diesel, alcohol or nitrous oxide (NOS or N2O) can boost power back to normal and over. Other than methanol alcohols can be used, ethanol, butanol, pentanol or n-octanol. When alcohol molecules became longer they contain more energy, so n-octanol is propably best, or to use Ecanol-type mixtures (Ecanol is mix of different alcohols). NOS can be stored as liquid in airplane or in ship in cold temperature. Using more powerful boost additivies like nitromethane or tetranitromethane or nitroethane can boost performance further. Different ethers can be used also. Storing those gases as cold liquid is possible in aircraft or in ship if they are in gas form in room temperature. Acetylene, acetone, picrite, and hydrazine with nitromethane are used as (diesel) additives. In eng-tips netpage “Internal combustion engine under water” 2009 is hydrogen peroxide- water- ethanol engine that does not use oxygen and uses 42% water as fuel. Using hydrogen peroxide engine Glenn DeRosa has patented “flywheel engine” that uses hydrogen peroxide rocket or explosions to power flywheel and that powers electric generator. Same principle can be used with other explosives also. In diesel or gasoline engines using ethers or alcohols instead or together with oil (diesel, gasoline, jet fuel) and mixing that with water can make powerful engine. Dimethyl ether, “zip fuel”, boron-ether, boron-gel fuel (that has viscosity of water when it warms up), oxygen enriched fuel etc. with water. Other high energy sources with water like high explosives, liquid gun propellants, and rocket fuels can be used in aircrafts perhaps if not in ships. Hydrogen peroxide with kerosene is used by swedish navy. Hydrazine, DMAZ, ammonium nitrate, hydroxyl ammonium nitrate, nitrocellulose, hexamine with additive etc. fuels or explosives that can be controlled when mixed with water as fuel mixture. “Review on synthesis and properties of high-energy density liquid fuels: hydrocarbons, nanoluids and energetic ionic liquids” 2018. “Hydrogen peroxide fuel for automobiles” 2007. Alcohol / ether, NOS, diesel oil, and water can all be in fuel mixture together, or more exotic fuels can be used with diesel oil and water or even without diesel oil, but water is always in mixture because it saves fuel in ships and aircrafts. Acetylene or ALICE or other fuels mixed with water etc. This mixing can be done in cylinder / jet nozzle or before fuel enters cylinder or jet nozzle if fuel mixture is not so dangerous. In aicraft turbosteamer principle can perhaps be used only sporadically when plane flies in suitable humid air, because turbosteamer uses lots of water. ATEG electric generator / thermodynamic cooling can be used in engines also. Diesel engines use urea to clean diesel emissions, in aircraft and in ships simply using toilets as source of urea can be used, and as source for hydrogen peroxide also, and when hydrogen peroxide is separated from human urine from toilet waste during flight it can be used as fuel in aircraft, or as ship fuel in ships. Patents US 33154058A and US 4038952 (1977) are old but perhaps useful. During WW2 germans used C Stoff (methanol, hydrazine, water), T Stoff ( hydrogen peroxide, water) and Z Stoff ( calcium permangate, sodium permangate, water) rocket fuels, water was integral part of them, and those chemicals are “biofuels” more or less, so something similar in high energy water-based fuel mixtures can be used. Nitrogen enriched (Ricardo liquid) diesel has been proposed. “Jet fuel from seawater” (Audi) needs electricity as electrolyte so its is not as good as simple acetylene engines etc. Water content in fuel mix can be over 40%, 45%, 50% or even 60% if remaining fuel mixture is high energy type. Turbosteamer- effect can be used to increase power in ships at least, and possible perhaps in aircrafts also. Internal combustion engines that use fuel / water mix can be piston / pistonless, rotary engine, swing piston-, axial-, cam engines etc. unusual types, and can be either diesel or Otto-cycle, split cycle, six stroke etc. types, laser ignition etc. can be used. Water can be used as fuel in three different ways: 1 : Fuel is made using chemical reaction between water and other material (carbide lamp) or energy is generated from chemical reaction between water and some other material in combustion chamber. Both of these can be combined: sodium and potassium with water generates heat and hydrogen, both heat and hydrogen can be used as energy source. 2: Water is used in fuel - water mixture, to cool otherwise hot combustion and using steam from water as additional energy source and dampen combustion pressure wave. 3: water is used as turbosteamer. All those three methods can be used separately, or two or three of them together, in same engine. Water as fuel -water mixture can be used in three ways: 1: As water fuel mixture / emulsion fuel liquid, 2: Sprayed at the air intake before combustion together with fuel. 3: Direct water injection in cylinder before, during and/or after combustion. These three methods can be used separately or together, even in same engine. Like this: Fuel is easily vaporated or dangerous, so it is blend with water to make it more easily storable. This fuel water mix is sprayed at air intake or direct injected to cylinder, but simultaneusly more water is sprayed at air intake to cool incoming air and incrase its density, so more air comes to cylinder. And lastly when this fuel water mix detonates, during and after combustion even more water is direct injected to cylinder to cool down and dampen combustion heat and pressure wave and turn this energy to steam that is more safer to engine to handle if high energy fuels are used. If from total amount of fuel mix in every stage 20% water is added, first 20% water to fuel blend, then 20% water to air intake cooling, and then 20% more in combustion stage, overall fuel mix has 60% water and only 40% fuel itself. High energy fuels and oxidisers are perhaps needed. But ordinary diesel engine with little modification can stand 40% water in diesel oil. Making diesel oil - alcohol / ether mixtures, with nitrous oxide, or use nitroethane, nitromethane, tetranitromethane, or nitro-something, or other high energy fuel, with or without oil fuel (diesel, jet fuel or gasoline). Even rocket fuels or high explosives can be used if water amount of fuel mix is perhaps up to 80% to dampen energy of explosion inside chamber so that cylinder head will not blow off. But Reactivity Controlled Compression Ignition, Spark Controlled Compression Ignition, Transonic Combustion fuel injection, Stratified Charge In Spark Injection, Jet Controlled Compression Ignition, Turbocharger Homogenous Charge Progressive Combustion, Four stroke hybrid pneumatic spark injection, Orbital Combustion Process (OCP, PlexDi), Grail engine FS-HCCI combustion, Premixed Charge Compression Ignition PCCI, Turbocharged HCPC (diesel) engine and laser ignition is made to handle this kind of situations. Large cruise ships and ocean liners are big, and large warships also, they have thousands of passangers and crew. They produce large amount of biowaste. If there is biofuel reactor inside large passanger ship, ship can make its own biofuel at least partially, biodiesel etc. Those ships are so big that biofuel reactor easily fits in. Smaller biofuel reactor is urea and hydrogen peroxide from urine separating machinery. It fits inside passenger aircraft, urea is used to clean diesel emissions and hydrogen peroxide can be used as fuel in aircraft. These are examples of from WC to fuel tank- cycle of materials. Big passanger ships and warships also spend months at sea, so turning biowaste to fuel is a way to get rid of biowaste that otherwise needs large waste management space already, if passenger ships collect the biowaste they use and only empty waste tanks when they are at harbour (new passenger ships). Instead of paying for waste management ships can turn waste to fuel, and save money because they produce fuel from waste, and both waste and fuel is costly, so savings are signicant if only partially ship can replace diesel fuel and use self-generated biofuel. If water is used in fuel mix even high explosives and rocket fuels can be used in internal combustion engines or jet engines, if water is used in suitable ways to dampen heat and explosive energy of high energy “fuel”. But almost ordinary diesel engine can use water fuel mix, or Otto-cycle engine with suitable ignition method, and oil based fuel can be mixed with alcohols, ethers, nitro-something compounds, picrite, acetylene, nitrous oxide and other oxiders etc., and this fuel mix is mixed with water to make water-fuel mix. Or use alcohol and/or ether etc. without oil based fuel in fuel water mix. Diesel engine can also use nitrogen to boost performance (Ricardo). There are other than diesel and Otto-cycle engines, there is six-stroke, five-stroke, Reisser cycle, Doyle engine, split cycle etc. fuel burning cycles. Paraffin biofuels are best for diesel engines. Turbosteamer used in ships, if it makes possible 15% fuel savings, is suitable for all kind of marine engines (turbosteamer is simply water sprayed outside cylinder block to cool engine and turn heat to steam and this steam goes to turbine, turbo-compound turbine, or turbocharger). Turbo-compound method also, used in aircraft engines, can be used in large ship engines etc. Turbo compound is turbocharger whose turbine propels engine powershaft, instead of normal turbocharger that is used to increase air amount to engine only. Altough increasing water to fuel decreases its energy content, using suitable high energy additives in fuel this disparity can be corrected, or changing fuel completely to high energy type. Making fuel or energy from chemical reaction between water and some other material is also a way to use water. If fuel produced from this chemical reaction (acetylene or hydrogen or other) is dangerous and too powerful, additional water can be used as fuel- water mix to make this fuel suitable in engines, so water is used to generate fuel itself and then more water is added to make this fuel safe for engine use, and turning water to steam in combustion with fuel also increases power efficiency. If it is not safe to use fuel generated by water using chemical reaction with other material in internal combustion engine, piston- or pistonless form, because that fuel is dangerous vapour, explosive or burns too hot, it can be still used in Glenn DeRosa s “flywheel engine” or in turbo compound section of ICE in “turboprop” afterburner like Napier Nomad engine. DeRosa s flywheel engine is designed to burn dangerous fuels or explosives, using burning rocket or explosions to power flywheel rotor turbine. Napier Nomad was diesel engine that used additional “turboprop” in turbo compound section for additional power. Small marine diesel engine can have turbo compound “turboprop” added, it works as turbodiesel when fuel is not used in turbo compound section, but when dangerous fuel is burned in turbo compound section extra power is in use. This marine engine is two-fuel engine, using diesel / alcohol etc. fuel with water and other additives in diesel engine, and using water with some reactive material in turbo compound section to produce fuel that is burned together with heat that this reaction generates in turbo compound section, together with additional water to tame down combustion heat and energy. Only diesel fuel mix without water for diesel section and reactive material for turbocompund section is needed to carry, water for diesel and turbocompound comes from ocean and it is filtered before it enters engine. Also turbosteamer can be used to improve performance even further without using extra fuel. Also aircraft engines can use this two fuel principle, but water must be separated from air humidity, airplane flies at high speed so it meets lots of air, and this air contains water, this water must only be separated from air so that engine can use it. Aircraft diesel uses fuel mix together with water from air as fuel-water mix, and this engine has turbo compound section like Napier Nomad, using fuel and heat from chemical reaction between water and some other material. Water for that chemical reaction comes from air also. Turbosteamer is out of question, it consumes so much water, so engine is air cooled or closed circuit water cooled. But perhaps in some very humid athmospheric conditions turbosteamer can also be used in aircraft engines sporadically, when air dries air cooling or closed water cooling is used again. Only diesel fuel mix and reactive material is need to be carried in plane itself, rest of “fuel” (water for fuel-water mix of diesel engine and for chemical reaction in turbo compound) comes from air itself. So this makes air travel signicanly cheaper, and diesel power also. Large marine engines are heavy and withstand high forces so even dangerous fuels can be used in them. Small marine ICE engines and aircraft ICE engines can burn dangerous fuel in “turboprop” turbocompound mode, small jet engine type turbine burns dangerous fuel. Turbofan or turbojet aircraft engine can also burn (with water injection in jet nozzles, same can be used in turbocompound engine) dangerous fuel from chemical reaction between water and reactive material. Additional water makes burning cooler and increases power in jet type engines, in similar way like diesel engines with water. Some ICEs like Liquid Piston X use sophisticated burning cycles, so not just plain diesel or Otto cycle engines are needed. Piston- (like stepped piston, opposed piston, OSP opposed stepped piston engine etc.) or rotary-, pistonless etc. engines. Glenn DeRosa s flywheel engine performance can be improved using additional water in “rocket” or explosion to generate steam and more power. This flywheel engine can also be used in aircraft perhaps. Also only using fuel from chemical reaction between water and some other material in internal combustion engine fuel water mix and in turbo compound afterburner also. Or then using only oil / alcohol etc. fuel-water mix in internal combustion engine with turbo compound that does not have “afterburner” or that afterburner uses same fuel that internal combustion engine uses, without water in afterburner fuel mix. Turbojets used sometimes water injection to improve power. If enough water is separated from air and then injected to jet turbines turbojets can use water injection all time, not just in takeoff, and this “fuel” is free and plane does not have to carry it. Only suitable procedure how airplane can separate enough water from air humidity so that it can “refuel” itself through flying is needed. In aircraft diesel engines perhaps less water is needed than in turbojets / turbofans in fuel-water mixture. If fuel generated by water in chemical reaction is dangerous, also using old gas turbine or steam turbine or steam engine principles is possible, dangerous fuel can be used in them more often than in piston engines. Modernised versions of gas / steam turbine has been made, and modern improved steam engines also, at least in theory. TurXbine, Turbocombustion Green-Engine, Wavedisk engine / generator, CHB-Evo etc. can be used. Comprex / pressure wave superchargers can be used in ICE - turbocompound engine. VTES and Rotrex are turbochargers. Free piston engine is not connected to crankshaft so it is safer (?) to use with explosive fuels than ordinary piston engine. In Wikipedia page “Advanced steam technologies” is modern steam engines. Steam turbines or engines perhaps handle better dangerous fuels like acetylene and hydrogen, if fuel is produced from water with calcium carbide or sodium or potassium etc. Steam engines or turbines can also be build cheaply perhaps in development countries, in India firms and companies make steam engines already. Calcium carbide price is 0,4 dollar / kg, if water is used as 50/50 mix to get fuel (I don t know how much water compared to calcium carbide carbide lamp uses) price is only 0,2 dollars for fuel kg because water is free. It is signicanly cheaper than gasoline (about 10 times cheaper). Sodium and potassium are propably even cheaper. Other chemical reagents are also possible if they generate fuel with water. In third world countries cheap fuels and cheap engines are needed, so perhaps steam engine or steam turbine, built locally, and using water as fuel with chemical reagent can make cheap engines, generators for electricity and lamps etc. possible. Those steam engines and turbines can be small, like those indian build few horsepower engines (they however also make bigger engines). And acetylene engine can be used as lamp during night when not used as engine during day. Because those engines and turbines are using water as fuel and other cheap chemical they are suited for third world countries as cheap energy source. Also piston engines etc. can be used and other ICEs. At least marine steam engines or turbines are possible. And Glenn DeRosa s flywheel engine, it is one version of gas / steam turbine and can be build in third world countries. If diesel engine is used with turbocompound section / afterburner, diesel engines and turbocompund sections can be sold separately as separate powerpacks and manufactured by different makers, because diesel engines and turbocompound afterburners (when “afterburner” is used it is small jet engine / turboprop) are different technology and afterburning turbocompound is almost jet engine tech. If turbocompound section is simply bigger supercharger than ordinary turbocharger and connected to powertrain it can be build and sold with diesel engine, like diesel truck engine manufacturers do nowadays. Modern improved efficiency steam engines and turbines, gas turbines etc. used with water fuel can be used in third world and elsewhere, and water fuel ICEs. Steam & other turbines like TurXbine, Quasiturbine etc. Turbosteamer is one version of steam turbine. TurXbine, Quasiturbine, Comprex / pressure wave supercharger, VTES supercharger, Rotrex traction drive, Volvo triple boost, Volvo PowerPulse, electric supercharger, Fibonacci Offset Rotary, etc. can perhaps also be used in turbocompound section instead of ordinary turbocharges, if thay have advantage over ordinary turbo in turbocompound use. Quasiturbine can also be used as (steam) engine itself. Tiny Tech Plants, Global Instruments Corporation, Sri Ram Engineering are indian steam engine manufacturers. Dearman Engines and DiPietro rotary engine are engines that use pneumatic air as power and have high efficiency with compressed air, turning them to steam power is perhaps (?) possible. Searching in Youtube for “Improved steam engine” brings many results. “Advanced unilow steam engine” is in internet. Like “Advanced uniflow Rankine engine (AURE)”, “Two-stroke uniflow turbo-compound IC engine”, “The uniflow generator” by Uniflow Power Ltd is combined heat, hot water, and steam engine source, it can be used in third world. “Trochilic engine” (swing piston type), “Harmonic uniflow engine” 2016, “Preliminary design of a two-stroke uniflow diesel engine” 2013, Facebook: “CR 500 - Different two-stroke design types A two stroke…” 2011, and eng-tips netpage “2 Stroke reverse uni-flow cam engine” 2017. If other ICE engine types are not suitable for acetylene or hydrogen engine that uses water as fuel with chemical reagent (if mixture of that chemical or mineral etc. with water is too explosive or too hot the engine to handle even with additional water used as coolant and to dampen explosive power), at least steam turbines or steam engines could be used. Not only reactions that produce acetylene or hydrogen with water, other chemical reactions that produce either heat or other flammable high energy gases with water can also be used, or reactions that produce both heat and fuel. Wavedisk engine etc. and other new ICE designs can perhaps handle forces and heat of high energy fuels with water. Ceramic engine, for example rotary type, can be used as ICE or steam engine or pump, depending on type. In netpage Greencargongress and netpage Evdriven in section “Concept engine” are different new ICE types. Like Libralato, Pneumatic hybrid engine, Libertine FPE engine, OX2 barrel engine (rotary), Garric rotary variable compression, RadMax vane rotary diesel, ReveTec aircraft engine, Bladon micro jet engine. Other like Shell concept engine lubricant, thermochemical exhaust heat recuperation, Clarke-Brayton split cycle engine, Fixed Pitch Continuous Variable Transmission, SCI HyMod modular hybrid car etc. new concepts. Other are Farrington engine, Hypocycloidal engine, Halo Liney 5 cylinder radial, Innas Noax Chiron free piston engine, Pescara engine, “Concept: Ultra-efficient, two-stroke Bonner engine”, Jonova engine, Fibonacci Offset Rotary steam engine, “Swashplate type 12 cylinder air/steam engine”, Tronjon Power Generator, Cyclone Power steam engines. Wood gas and Rocket stove are other ways to use biofuel, in steam or ICE engines, steam turbines etc. Using pelletized biomass etc. fuel is also possible. Uniflow Generator by Uniflow Power ltd is electric, hot water and heat providing steam engine. If it would have direct power output option, it could be used as pump also, becoming power source of pump when connecting to it. Using high explosive like ammonium nitrate or nitrocellulose with water to dampen explosive power in these steam engines and turbines or rocket fuel like ALICE, or hexamine etc. is perhaps possible if similar is not possible to use in ICEs. C-4 is explosive that is being phased out by military, and C-4 stocks are becoming chemical waste. Using those old military C-4 stocks being phased out as fuel source for steam engines or turbines, ICEs etc. chemical waste (C-4) can be used as high energy fuel. If C-4 and water is mixed in combustion perhaps explosive power is controllable enough to be used in engines and (steam) turbines. Rocket Stove or other steam engine / generator / turbine can be converted to use those dangerous fuels, like hydrogen, acetylene, explosives, rocket fuels etc. with water and / or nitrogen like Ricardo diesel engine to tame high energy fuel explosive power and turn energy to steam. LanzaTech makes ethanol fuel from industrial waste gases. Aquarius Engines is single cylinder high efficiency engine. Instead of using stored hydrogen in engines using hydrogen produced “in situ” inside engine with water and some chemical reactant that together produces hydrogen is better. Also now heat that this reaction produces (and hydrogen also) can be used in engine itself. Acetylene or other reaction products with water or just heat that water produces with some chemical reactant can be used in ICE / steam engine. Water is “biofuel” and it is free, not like ordinary biofuels made from biomass etc. Only chemical reactant is needed with water, and some of those reactants are cheap also. Or then just use water as fuel additive like in diesel engines. Instead of engine using stored acetylene or hydrogen if those dangerous vapors are produced inside engine itself, in combustion chamber etc. It is safer and simpler than storing dangerous fuels at tank and then transport this dangerous fuel around. And using water to produce fuel is possible with chemical reaction, or to use water to produce heat that engine can use with chemical reaction, or both inside engine, because chemical reaction often produces both heat and fuel when water is mixed with some chemical reagent, catalyst, or something similar. Other way is “Direct air capture” CO2 from air combined with hydrogen of water to make diesel fuel, firms like Fuel Air Systems, Carbon Engineering, Global Termostat, Climeworks are doing these, SOLETAIR project etc., but it needs more energy to make diesel fuel from air and water than is energy content of fuel which is the end result. So combining biodiesel with water is better. But water can indeed be used as fuel in several different ways. Water is cheap, so in third world countries it could be used as “fuel” with fossil or biofuels, or with reactive chemicals. Turbosteamer can be used to improve engine efficiency for 15% more. Chemical compound, reactant, or catalyst etc. that produces either heat or fuel with water, or both, can be used in “water fuel engine” or steam turbine. Other way is to use water only as fuel additive, high percentage of water in water-fuel mix.