The energy storage
storage is part of a series
of briefing documents on the problems of power consumption,
posed by the steady depletion of fossil fuels and most particularly
of pumpable oil.
One of a grouping of documents on global concerns at abelard.org.
|on energy||on global warming|
housing and making living systems ecological
sustainable futures briefing documents
|Tectonics: tectonic plates - floating on the surface of a cauldron|
If energy is not wanted immediately, for instance to switch on a light, some means of storage of energy required for later use has to be achieved. A battery, a dam, a gallon of petrol, a hydrogen fuel cell, a log for the fire, or radioactive sources, are all means of storing power/energy.
Learn to think clearly about the difference between generating and storing power.
Even insulation your house and increasing efficiency of processes, thus countering waste, has similarities to storage.
All conversion to energy involves inefficiencies. Energy may be converted to storage or to produce work. Thus, energy is involved in manufacturing a battery or fuel cell, energy is used to charge up the battery. After that, the energy in the battery may be used to drive a car, or to run a laptop computer.
Oil, in the form of gas (petrol) or diesel, may be used to run a car, or the oil may be used to drive electricity generators in a power station. The electricity may then used to charge a battery, and the battery then may be used to drive a car. At each stage, energy is lost through inefficiencies. These inefficiencies contribute to making storage a bottle-neck issue in cleaning and modernising energy production.
Salt energy storage is more efficient with tower solar units than with parabolic units.
With parabolic mirrors, molten salt is run through the tube, instead of oil. Thus, there are much longer runs of piping over a whole field of parabolic mirrors to be heated, rather than the sun’s heat being directed on a central tower and there absorbed by the molten salt. So, for parabolic mirror systems, more piping, molten salt and insulation is required, making this storage method more applicable to the tower configuration.
Hydrogen and methanol are fuels created as a means of storing energy effectively.
As well as producing hydrogen by electrolysis, the gas can be made by high-temperature disassociation. The heat generated by a solar power plant could be used for making hydrogen, as well as for driving steam turbines or, perhaps, space heating.
By running a nuclear power station at higher temperatures, using the heat directly to split hydrogen from water, 40 – 50% efficiency can be achieved from a nuclear power plant.
Other, more esoteric methods include flywheels (also used for smoothing power output), capacitors (including super-capacitors - experimental), and even underground gas compression is under sporadic discussion.
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© abelard, 2008, 2 july
the address for this document is http://www.abelard.org/briefings/energy_storage.php