Think of nuclear fission: it generates useful energy but if it runs out of control you get a cataclysmic explosion.
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Dr Kanatzidis argues that wherever heat is generated as part of power generation, thermoelectric devices could help extract more useful energy.
It is as useful to save energy as it is to save time or Christmas wrapping paper.
Nor even that it is possible to extract as useful work all the energy in gasoline or any other possible violation of the laws of thermodynamics.
Certainly, microwaves would work: a test carried out in 2008 transmitted useful amounts of microwave energy between two Hawaiian islands 148km (92 miles) apart, so penetrating the 100km of the atmosphere would be a doddle.
Harness a few thousand of these minute bursts of energy, and some useful work could be done.
Unfortunately, because of their higher strength and toughness, HSLA steels need 30% more energy to form them into useful shapes.
Some of this story is told in a patchy but useful book by Herbert Inhaber, Why Energy Conservation Fails (Quorum, 1997).
Research suggests that up between 20 and 30 gigawatt-hours (GWh) of electric energy could be stored as useful heat in hot water.
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If only some way can be found to transport and store hydrogen, the fuel cell has two powerful things going for it: It doesn't pollute and it converts 55% of the chemical energy in the fuel into useful work.
Some of the ideas are useful, such as strengthening the International Atomic Energy Agency as a proliferation watchdog and beefing up safeguards and verification mechanisms.
There are many nontrivial ancillary challenges too, especially the secondary procedure of actually getting the energy out of the reactor into a useful form, i.e. heat to drive steam-turbines as with all other kinds of thermal power stations, to generate electricity.
VSATs permit big broadband transmissions, useful for Inmarsat's traditional customers: maritime and energy companies and governments.
In rigorous testing, the Energy Department said, the bulb had a useful lifetime of more than 25, 000 hours.
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With many nations increasingly focused on the notion of energy independence, the pressure to increasingly extract all useful local resources is also increasing.
The small size of the LED light chip allows another advantage arising from the physics of optics: Engineers can employ collaterally small lenses making it possible to efficiently extract, direct and focus the lumens, achieving useful illumination with far fewer lumens--and far less energy--wasted.
Lands with fertile soil, useful minerals, navigable waterways, proximity to trade routes and easy energy sources enjoy a leg up over groups inhabiting less fortunate locales.
Instead, it is most useful as confirmation that a person should buy something on eBay rather than spend time and energy researching the product on other sites.
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It could be useful to denote things such as the sun's mass (2.2 hellatons) and energy output (approximately 0.4 hellawatts).
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Another strategy involves using less energy (100 kV instead of the standard 120 kV), which is effective but useful only for patients who are not obese.
Some of it is going on useful things like roads and schools and paying off debts, some gets recycled, flowing back to energy-thirsty countries in the form of higher demand for their goods.
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