were dripping gasoline

each 0.1 milliliter drip

containing enough energy

to heat a quart of water

one degree Fahrenheit

or (theoretically)

to power a one-watt device

for one hour

so a 100-watt lightbulb

consumes the equivalent

of 100 drips per hour

(one slow drip

every 36 seconds)

a solar panel

to produce 1 watt continuous

(one drip per hour)

can be as small as a 3*5 card

(3*5 feet for 144 watts, then)

a hand crank generator

can do 10-50 drips per hour

a bikepedal generator 100-200

the same gallon of gas

that propels your car some dozen miles

(with 20% mechanical efficiency)

or a 747 just 1000 ft

is 45,000 drips

(200 drips for a penny)

or 45 kilowatt-hour equivalents

19 days of 100W light

19 days of every-36-seconds drips

to fill a gallon can

5 cents per 1000 drips of gasoline

5 cents per kilowatt-hour of gasoline

in the USA a kilowatt-hour of electricity

costs about ten cents

or $4.50 for the energy equivalent

of that $2.25 gallon of gas

or $3 for 1.5 gallons of butane

or $2 for 125 cubic feet of natural gas

or $1 for 30 pounds of firewood

or 50 cents for 15 pounds of dirty black coal

or 25 cents for 5 milligrams of nuclear fuel

that gallon of gasoline

applied to heating water

would raise the temperature

of 250 gallons (ten showers worth)

by 50 degrees Fahrenheit

4 drips per degree per gallon

45 cents per electrically-heated shower

fuel cells aim to achieve

40% efficiency

converting methanol to electricity

but methanol has half the energy of gasoline

so a 500-drop fuelcell reservoir

may deliver 100-drops of gasoline-equivalent

powering a 10-watt device

for 10 hours

(butane lighters' reservoirs

by comparison

holding less than 50 drops)

an AA battery delivers

just 4 'drops' total

an AAA just 2

a 9v 5

9v lithium 10

a C 12

a D 24

a button-sized nickel-cadmium cell, 1 drip

a nickel-metal-hydride cell 2

laptop batteries 50-100

car-batteries 1000

standby-mode

in many 120V appliances

'drips' about once per hour

battery chargers

drip faster than this

wasting more drips than they recharge

a computer system drawing 300W

drips every 12 seconds

as would, on average

an electric hot water heater

a refrigerator maybe every 30 seconds

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