An alkaline cell with sufficient power density may soon, however, be on the way.
Nor can they compare to the power density of sources like natural gas, oil and nuclear.
The first of the Four Imperatives, power density, is the most telling of the rates.
This amount of power density far exceeds anything else done with microbial fuel cells.
The engine performs with a level of efficiency close to diesel, but sacrifices some of the power density.
Common metrics of power density include: horsepower per cubic inch, watts per square meter and watts per kilogram.
Power density refers to the energy flow that can be harnessed from a given unit of volume, area or mass.
Corn ethanol's low power density is inherent in all biomass, which leads us to the second of the Four Imperatives.
Every 12 months or so GM develops a new generation of fuel cells, and recent improvements in power density and part streamlining are impressive.
But doing so will mean replacing high-power-density sources that are reliable and low cost with low-power-density sources that are highly variable and high cost.
The technological advance of thin and light flexible display has encouraged the development of flexible batteries with a high power density and thermal stability.
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Those numbers explain why power density matters so much: if you start with a source that has low power density, you have to compensate for that low density by utilizing more resources such as land, steel, and ultra-long transmission lines.
If a source has low power density, then it will likely require too much real estate, material or space to provide the power that we demand at prices we can afford or in the vast quantities that the world needs.
It turns out people just prefer thinner phones (or at least initially they do), and therefore HTC chose to take a holistic approach to improving battery life through power management optimization, choice of power density, choice of voltage and many more.
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The power density of processor chips used in PCs today is on a par with that inside a nuclear reactor--and anyone who's ever perched a notebook computer on his lap for a prolonged period knows all that power often manifests itself in excess heat.
Simple math shows that a marginal gas or oil well has a power density at least 22 times that of a wind turbine while a nuclear power plant has a power density that is more than 8 times that of a solar photovoltaic facility.
While conspiracy theorists may want to believe that Big Oil, Big Coal and Big Nuclear are stifling the growth of renewables, the simple truth is that coal, oil, natural gas and nuclear can satisfy the Four Imperatives: power density, energy density, cost and scale.
The firm says the low power-density of its lasers and a series of safeguards ensures that human exposure remains within regulatory limits.
The key to understanding Saint-Julien is to try and think of the style of wine as somewhere between the perfume and elegance of Margaux and the power and density of Pauillac.
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We have good designs to do that blades, discrete rack mount servers and a new scale-out line which is aimed at financial services or web 2.0 where power, density, cooling and acceleration by GPUs all comes into play.
New ARM-based server all around lower power utilization, high density. 3Par has better solution in storage.
This would create a fluid that, although a gas, would have a similar density and cutting power to that of water.
Operating with a voltage of 1.35V, according to Samsung tests it provides an average 70% power savings (per unit density) over a 50nm class equivalent, 1.5V DDR3-based RDIMM.
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In addition, the inherent benefits of the platform, including the helium fill, allow HGST to significantly improve datacenter TCO on virtually every level: capacity, power, cooling and storage density.
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Birds were given different colors, squawks and abilities such as extra density, acceleration and the power to lay explosive eggs in the air before winging off their parabolas from the counterforce of laying eggs.
Figure 2 in the accompanying power point file shows historical storage areal density (AD) growth for HDDs (this is directly related to the amount of digital storage that can be put on a disk in a hard disk drive) from Q1 2000 through Q1 2011.
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The batteries themselves make use of the same zinc air technology used in hearing aid batteries, and apparently have the highest energy density of any portable consumer power solution, which translates to about three times the runtime of a similarly sized alkaline or lithium ion battery.
ENGADGET: Energizer introduces thin, powerful Zinc Air Prismatic battery
The figure is a measure of circuit track density and broadly relates to processing power and energy consumption.
The result is a much greater density of the gates, lower power consumption, faster switching and fewer quantum side-effects.
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