New answers tagged energy
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Energy is energy. You can use it to run any motor you want. You can heat objects. You can make light. You can propel objects. You can generate electrical charges large and small. Lightning, if you want. Zero-point energy is just another energy source. There is nothing special about the energy produced, so there is no special use for that energy. Anything you ...
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Food is very energy-rich
Here's an energy density chart. This is an amount of energy produced per kilogram of reactants. Gasoline reacting with air produces 13.3 megajoules per kilogram. And here are similar numbers for digesting food. Note: kilojoules/gram works out to be the same as megajoules / kilogram (there are 1000 KJ per MJ and 1000 grams per ...
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There is already a technology which may be applicable for your purposes: radioisotope thermoelectric generators, or RTGs. These convert the heat released by the radioactive decay of unstable elements into electricity, have been around for over 60 years, and have no moving parts. A Plutonium-238 RTG generates 0.57 watts per gram (so a 20 kg RTG would ...
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See "Shipstone" in R.A. Heinlein's novel Friday.
See "Molecular Distortion Battery" in Niven's Known Space novels.
Both give it a name, and ignore the details.
H. Beam Piper refers to isotope powered nuclear batteries. The batteries are armoured in collapsium. In effect a single layer of nuclei. About the same weight penalty as a foot of lead. The best ...
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The nucleous of the planet could be pretty hot and provide enough energy for a stustainable life.
If the nucleous of the planet contains a enough radioactive materials, it could continue producing heating for billions of years, enough to allow the formation of a complex life.
The main problem is that there could be no photosynthesis, so no oxygen, or ...
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I have plastic packet with rice seeds i bought at general store this week, and i plan to eat them for breakfast.
They claim each 100g of this rice (one coffe cup) gives human consumed this product 1415.1 kilojoules of energy. If we manage to fully convert this energy to heat, and considering specific heat capacity of water to be equal 4220 Joules per kg and ...
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Let's take a plant with C4 photosynthetic pathway in a tropical zone for some quick maths.
Average insolation in a tropical zone is ~400 watts per square meter.
Photosynthetic efficiency on wikipedia gives us a high of 6% actual efficiency (not theoretical) at converting solar energy from our sun due to many factors such us how much of the sunlight's ...
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Welcome to the stack! Great question!
The core of the planet would still be quite hot, meaning that volcanoes and underwater vents could occasionally release hot (and therefore high-energy) bursts of liquid/gas into the environment. Perhaps this could be harnessed, somehow...?
This is the most likely answer, and it's occurring right here on Earth as we ...
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Broadcast power!
https://en.wikipedia.org/wiki/Wireless_power_transfer
Can I invoke wireless power transfer without showing Tesla's tower? Nope.
The idea: power things remotely using radiation that can travel thru the air. Your robots have power transmitters back at the base (hopefully a mushroom shaped copper-clad tower) or maybe in orbit, or mounted ...
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manipulate electricity with their bio battery electric organs and I want these characters to have the ability to shoot powerful lasers, plasma projectiles etc but I am unsure how they could store that much power to allow them to do repeated attacks.
jdunlop has the right answer to the specific question you asked, but there's another element to this you didn'...
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There is no way you can get around this problem with current or near-future technology - energy density is the major problem with battery-electric vehicles, and they're not trying to spend enormous amounts of power with energy weapons.
(Side note: if you're worried about the science-based power constraints, there are major problems with energy weapons ...
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This is the kind of question for which an axe-cut approximation is well worth it.
Let's take a human, and observe how he/she is made by various things: muscles, bones, hair... well, let's approximate all of this with water.
And, since we want to generalize, let's take 1 liter of water, which conveniently weights 1 kg.
The heat of vaporization of water is ...
answered Dec 2 at 17:54
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Sand also contains carbon (in the form of calcium carbonate), which can be used to make graphene.
Graphene is a much more versatile substance, and so would be a superior choice.
A thin layer of graphene would be super-strong, flexible, superconducting, capable of storing electricity, and and more efficient.
The sand on the ocean floor could even be used ...
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We know of no way to do this.
As to your particular nano-scale contraption, that one is actually a rather interesting little story. We've actually investigated the idea of capturing energy out of Brownian motion with nano-scale devices. The structure that we relied on was a water-wheel of sorts with a ratchet. The idea was that random collisions in one ...
answered Nov 27 at 17:14
Cort Ammon - Reinstate Monica
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Sure, we can do it today. As long as you are taking heat from a hot place to a cooler place, there's no problem with the second law of thermodynamics.
You can use a solar updraught tower. Works best where there's a lot of solar thermal energy. Take a bit of desert, or a nice big black tarmac area, build a tower to collect the rising hot air and funnel it up ...
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As it happens I've been putting a lot of thought and reading into this exact problem lately, and it's a real head scratcher. This problem comes up a lot when people talk about spacecraft design and waste heat issues. Intuitively it seems like obviously you should be able to capture heat and turn it into useful power.
The problem is Entropy. Here's a ...
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We can already do that, and no, it does not violate the laws of thermodynamics at all. This is called the Thermoelectric effect. As for doing this effectively at scale, it's generally more expensive than other means of heating, cooling, and electrical generation, so it's not done very much. There is research about it, such as this.
Currently it's ...
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This idea is violating the laws of thermodynamics.
Simply put, forget about it.
Thermodynamics laws are the best enforced laws in universe. There is no way around them.
Those laws clearly state that you cannot convert heat to usable energy, you can only convert a fraction L of energy from a temperature T1 to usable energy if you can discard some energy at ...
answered Nov 27 at 14:16
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Gravity-manipulation attacks. Something like the Mass Distortion spell from Might and Magic that greatly increases the recipient's mass, causing its internal structure to collapse in on itself.
Freeze it. Cold temperatures are by definition the absence of heat energy, which means you will cause damage that's physically impossible to absorb. Use a cold beam ...
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Levitation actually doesn't need to consume any energy. A well-constructed levitation spell simply suspends the conversion of gravitational potential energy into kinetic energy. This costs just about nothing. You would only need to spend energy to ascend, and you would recover energy from descending.
The inefficient way to do levitation is to produce a ...
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It's a photosynthetic organism with very efficient pigments. They have to be because the organism is a bipedal animal without leaves, not even elephant's ears. The efficiency comes at a price, and the price is being tuned to narrow spectral ranges.
When their skin is under the correct illumination it will convert carbon, water and light into glicose, the ...
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If we want it to be realistic, there is no way. This is result of few factors:
The solar radiation on the earth in the upper atmosphere (before it is reduced by atmospheric effects and clouds) is 1300 W/m^2. Human body surface is 1.9 m^2, and at least 1/2 of it will be facing away from the sun. Then following that the shape of your body will reduce the ...
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Clearly you're talking about a photosynthetic organism, albeit one with very precise responses to different wavelengths.
My suggestion would be a creature that evolved on a planet orbiting a ternary star system, where the wavelength of sunlight changes dramatically in a cycle with a period of months of years, and which has evolved such that this cycle ...
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This is a question about energy sources, not about hydrogen
Since you are not interested in all the points that differentiate hydrogen from other energy carriers, what remains is the question about the best energy generator.
It will be a mix.
Solar.
Wind.
Biogas.
Nuclear (though this is contested).
As long as it generates electricity, or enough heat to ...
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Since you have stipulated a distributed energy system and hydrogen is an energy carrier rather than a primary energy source, the landscape will be filled with repetitive iterations of hydrogen generators and pipelines. Since the hydrogen is being sent to houses, much of the infrastructure will not even be visible, much like natural gas pipelines in ...
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Laser Transmitting satellites
They are satellites that collect sunlight, and literally beam it to Earth in a concentrated form. We aren't even that far from being able to develop it if we really wanted to invest in it.
https://www.energy.gov/articles/space-based-solar-power
Laser transmitting satellites, as described by our friends at LLNL, orbit in ...
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Well, heck, if we're hand-waving both the difficulty of generating and the difficulty of storing, the answer is obvious: Antimatter.
The reason Nuclear Power has such a huge Energy/FuelWeight ratio is because it's not using a chemical reaction - its actually losing 0.1% of its fuel mass in the process. Which might not sound like much - a tenth of a percent ...
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I'm going to suggest solar.
There are a whole bunch of ways to power an electrolytic water-splitting scheme, but they all require some initial electrical source and a load of electrical hardware and the additional (albeit not too serious) inefficiencies of water electrolysis itself.
You can cut out the middleman by photocatalytic water splitting. Then ...
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