8 ms·
> The reactor must be able to generate an uninterrupted electricity output of at least 10 kilowatts. The average U.S. residential home, according to the U.S. En
by tromp 6y ago
> The reactor must be able to generate an uninterrupted electricity output of at least 10 kilowatts. The average U.S. residential home, according to the U.S. Energy Information Administration, uses about 11,000 kilowatt-hours per year.
Would be more helpful to express that as 11000/365/24 = 1.256 kilowatt, so you understand that the reactor could only power 8 U.S. homes.
Btw, what are non-residential homes?
- danielheath 6y agoHoliday homes, homes held as a capital investment and not leased out, homes of people who have entered long-term care but not sold the primary residence...
- gspr 6y agoI've always found the use of kWh/year so absurd. I mean Wh is kinda weird as a unit for energy, but this is just plain asburd.
- hurxnid 6y agoNot if you work in the power industry.
- bufferoverflow 6y agoWh is directly equivalent to joules. It makes perfect sense as a unit of energy. 1 Wh = 3600 joules
- ginko 6y agoThat's the point though. Just refer to it in joules.
- lukeschlather 6y agoIt's kind of like radians vs. degrees. Degrees seem ridiculous if you're doing trig, but working with irrational fractions of pi is ridiculous if you're trying to measure with a protractor. If you need to convert to radians to do some trig (and let's be honest you usually don't) you are going to end up converting something like degrees that are marked on the protractor anyway.
- thaumasiotes 6y ago> Degrees seem ridiculous if you're doing trig Degrees are ridiculous if you're doing calculus. They don't really pose any problems if you're doing trig. > but working with irrational fractions of pi is ridiculous if you're trying to measure with a protractor. Sure, that's true, but that's only because irrational numbers are by definition infinitely precise. It's no more difficult to use a protractor labeled in increments of 0.02 radians than one labeled in increments of one degree.
- lukeschlather 6y ago30/60 degrees are round numbers which are very useful for a lot of applications. Your .02 radian protractor doesn't have a mark on it for either.
- thaumasiotes 6y agoRealistically, it probably would; those marks would just not fit into the progression of .02 radian marks. Ever seen a meter stick that also measured inches? Are you trying to measure an angle, draw a particular angle, or confirm that an angle meets a particular standard?
- 6y ago
- matthewdgreen 6y agoMost utilities charge by the kWh, so this measure makes it easy to compute costs.
- Bx6667 6y agoWatt hours are the most widely used unit for energy in science and engineering ...
- gspr 6y agoI know (in the case of engineering anyway; I would hold joules are more used in science). I accept the convenience of Wh. The problem comes with Wh/x, where x is any unit of time. Why not cancel the h/x for a dimensionaless factor in this case?
- ginko 6y agoI never understood why kWh/yr is so commonly used.
- leetcrew 6y agowatt-hour itself is already a somewhat silly unit, since joule already exists and is part of the definition of watt. but people can easily multiply an appliance's watt rating by the amount of time they use it to estimate its monthly energy use, which makes it a convenient unit for billing. I would guess kWh/yr is an extension of this idea. you could use J/yr, but most people don't have an intuitive sense of how much power that is.
- iso1210 6y agoI'm just surprised that the U.S uses such metric units as Watts and Joules, rather than foot-pounds or calories
- Teknoman117 6y agoI'd imagine it has something to do with the timeframe that terms describing units of electricity came into common usage. The U.S. is a signatory of the Metre Convention (1875). All of our customary units are defined as linear conversions of corresponding SI units. The Watt and Joule (also Ohm) were not standardized until 1893. Funnily enough, the international conference where these were officially decided happened in Chicago.
- User23 6y agoThe USA more or less fully adopted the metric system in the 90s. All food is labeled in metric units for example. We just never abandoned imperial weights and measures. This leads to some amusing things like large bottles of soda and wine being measured in metric, while cans are measured in ounces. Then again we're not alone. The UK is considered officially metric, but they still pour beer in pints and weigh people in stone. There are good arguments to be made for everyday use of Fahrenheit over Celsius. The 0-100 range in F cover pretty much all of the temperatures one is likely to experience in the USA. It also has a finer resolution than degrees Celsius in everyday weather temperature ranges. The SI units are designed for scientific and engineering use and they excel for the purpose they are designed.
- unchocked 6y agoIt happens all the time in reporting. It seems to be part of the journalistic style guide to provide context to quantities by comparing them to another quantity. Here, both units contain the word "kilowatt" so they are used as comparisons. Of course it's innumerate, but that's a broader problem for our society.