Converting between energy forms (practical)

A matrix to explore energy conversion.

Forms of energy

Name Underlying effect
Light transport of photons. Should we distinguish between photon transport and waves ? (for example, distinguishing between photo-voltaic effect and radio waves)
Electricity transport of electrons (metal, conductor or semi-conductor, void), or ions (fluid)
Mechanical (move) macroscopic transport of atoms. Conversion to or from move should always incur losses due to friction
Mechanical (wave) transport of energy by means of mechanical deformation without matter transport ("sound", pressure waves in fluid or solid)
Thermal group of atoms internal agitation. Converting from thermal energy means using a temperature difference, converting "to" thermal energy means increasing temperature difference, either by heating or cooling.
Chemical recombination of atoms (molecules) with a different level of energy
Nuclear,thermonuclear recombination of atom nuclei with a different level of energy

(and more: anti-matter ! but not practical yet)

Non chemical

From To effect Reversible (meaning the same device works both ways) device typical name Efficiency (whatever it means)
Light Electricity Photovoltaic (Einstein Nobel prize !) ? panel should glow when a voltage is applied solar panel 10-20% ?
Light Electricity Electromagnetism Yes radio antenna ?
Light Mechanical (move) (name ?) ?No Crookes bulb ? (use intermediate heat effect ?), "solar sail" (does a prototype exist ?) ?
Light Mechanical wave ?Direct conversion of light into sound ???
Light Heat (hotter) Black body Yes (thermoluminescence) ? ?
Light Heat (cooler) Laser cooling. Is it possible to build a fridge that works directly from light ? Laser cooler
Electricity Light Electromagnetism,quantum effect (semi-conductor), plasma ?should be, from a theoretical point of view (however, getting a natural plasma source isn't easy !) radio antenna,LED,neon tube. NB: the light bulb is really a conversion of heat into light. ~100% (LED)
Electricity Mechanical move Electromagnetism Yes (dynamo) electric motor ~100% (losses due to ohm effect)
Electricity Mechanical (pressure) Piezo Should be piezoelectric transducer ?
Electricity Heat (hotter) Ohm No, but see Seebek Resistor ! 100%
Electricity Heat (cooler) Seebek Yes (Ohm) 100%
Mechanical move Light ?
Mechanical move Electricity Electromagnetism Yes (electric motor) Dynamo ~100%
Mechanical move Mechanical wave In theory. Practical application ? Drum ?
Mechanical move Thermal (hotter) Friction, thermal displacement No ? (2nd law of thermodynamic) Brake, heat pump 100% (from the point of view of energy conversion)
Mechanical move Thermal (cooler) Thermodynamic Yes (Stirling engine) Stirling engine, freezer
Mechanical wave Light Some materials emit light when moved (such as some fabric)
Mechanical wave Electricity Piezo Yes Pressure sensor ?
Mechanical wave Mechanical move ?Practical application (sound motor !)
Mechanical wave Thermal (hotter) Friction Practical application
Thermal light Thermoluminescence Sould be light bulb 20% ?
Thermal Electricity Seebek effect yes (can cool using electricity) Thermogenerator 6-8%
Thermal Mechanical move Thermodynamic Yes, can "produce" (displace) heat or cold when fed with mechanical movement Stirling engine for example 30% has been demonstrated
Thermal mechanical wave is it possible to get a sound by heating some material ? At least, it should evacuate heat at the same rate (to produce a wave)


From To effect Reversible device typical name Efficiency (whatever it means)
Chemical light photoluminescence other reactions ? ?
Light Chemical photosynthesis, photodissociation otherreactions Practical applications ? ?
Chemical Thermal exothermic reaction (very numerous) other reactions (endothermic) ? ?
Chemical Mechanical gaz expansion ? ??? Rocket ?


Not for the hobbyist...

From To effect Reversible device typical name Efficiency (whatever it means)
Nuclear Heat Fission, fusion, disintegration Only theoretical. The magnitude difference between nuclear and other forms of energy is such that reverse conversion is out of reach for practical purpose given the state of physics. Nuclear reactor ?
Nuclear Light ?
Nuclear Mechanical ?
Nuclear Chemical Practical ?
Nuclear Electricity The St Graal of energy production