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You proved my point.

4.5 kWh is not a lot of energy.

It's the amount of energy needed to light a 1K lightbulb for 4 hours.

It's a pittance compared to what you burn in you car.

4.5Kw/h won't get you around the block :)



I think you may be mistaken about amounts of energy. Typical modern domestic-use light bulb (ccfl) are rated around 20 watts. 100 W was the typical maximum in incandescent light bulbs for domestic use, excluding some very bright halogen bulbs at around 200 W. 1000 W bulbs are mainly used in studio applications (as someone else mentioned) and for stage lighting.

On the subject of getting around the block: A kilogram of gasoline contains some 46 MJ of energy. Gasoline is a bit lighter than water, so one kilo is around 1.3 liters. 46 MJ is equal to, roughly, 13 KWh, so 4.5 KWh are around 300 grams, or around 400 ml. A Manhattan city block is around 80x280 Meters, for a circumference of roughly 720 Meters. An inefficient modern car might use 8 Liters per 100 Kilometers, so 400 ml (or roughly 4.5 KWh) will move an inefficient modern car by around 5 Kilometers.

In other words, it'll get you around the block. Not once, not twice, but slightly less than 7 times.


4.5Kw/h won't get you around the block :)

4.5 kWh will take you nearly 20 miles in an electric vehicle. Not far short of what 1 gallon of gasoline will get you.


A 1kW lightbulb is rather bright and not used in homes, more so in studios. A better comparison might be 10 100W bulbs or maybe an average chandelier.


Even 100W bulbs are pretty rare now days (illegal in the EU), replaced with LED versions that consume far less energy.

4.5 kWh is really a tremendous amount of energy just to refine a single gallon of gasoline. And it's energy that's completely lost, just converting hydrocarbons from one form into another.

By putting that energy directly into electric vehicles instead, you'd be able to power around half of all the vehicles on the road!




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