58 MPG by 2032

[Grumpycat]

Watts are a product of amps and volts.

But the ability to deliver Watts for an hour is the true measure of battery capacity. Wh or kWh.

 

[aircommuter]

I was replying to the question about electric billing.

 

[Grumpycat]

I was replying to the question about electric billing.

Electric billing is also in kWh, not Watts.

 

[aircommuter]

Electric billing is also in kWh, not Watts.

It is just a thousand watts for an hour.

 

[WinterDeere]

At the risk of triggering anyone's PTSD from high school Physics class, kW is power, whereas kWh is energy. Power is energy divided by time, or the rate of energy transferred.

What you're buying for the electric company is energy, the product of power (watts) and time (hours), as aircommuter already noted.

 

[Grumpycat]

It is just a thousand watts for an hour.

Watts is significantly different than Watt-hours.

When you cutsie slang shorten Watt-hours to Watts the meaning of what you are saying totally changes.

 

[nickfank]

I'm chuckling that on a tractor forum we're discussing the difference between electrical power & energy, being careful to get our units right, talking about how wind resistance increases with the cube of the speed, and generally geeking out. Thanks for breaking all of the stereotypes in a positive way. Whether we agree or not on other issues, it's great to see people focusing on getting the facts and the math correct.

 

[nickfank]

Let’s start with *****’s campaign vehicle. A 747 followed by two F16s and KC 135 tanker. That’s what I call saving fuel! Cruise ships are guzzlers, not even necessary. Importing people wastes fuel too. The whole thing is an irresponsible folly. Agendas cannot override physics and electrical engineering principles.

I completely agree with the notion that private jets and other forms of conspicuous consumption don't set a good example.

I'll push back a bit on the use of the phrase "campaign vehicle". It's not that simple.

Our current sitting president was well known for using public transportation to commute to work when he was a senator. The massive vehicles that come with a full suite of communications equipment and security came with the job of president, and these vehicles are a requirement, not a choice. When he had the choice, the current president chose the form of transportation that consumes least fuel.

A president or vice president is *required* to use the vehicles supplied by the military and secret service, even on personal or campaign trips. However, when Air Force One is used for a campaign trip, the campaign must reimburse the Air Force for the equivalent cost of chartering a private jet. So the campaign pays for the basic transportation, and the taxpayers pay for the upgrade to vehicles that keep the president in communication and secure at all times. That's part of the job, not a choice, and there are reasonable rules in place around reimbursement for campaigning.

Source: https://www.npr.org/2016/07/07/485097272/fact-check-air-force-one-who-pays

If you're going to call politicians out for their conspicuous consumption, I'd say it makes sense to focus on those who, when not constrained by their work duties, *choose* to throw away fuel in a grand display of their wealth. It also makes sense to look at the number of personal or campaign trips they make while in office. I'll leave it as an exercise for the readers to assess who the worst offenders are by that measure.

 

[Williy]

How do you figure out example a car battery has 800 cold
cranking amps = how many KWH how to figure this??
How long would a lithium 100 ah battery last drawing 15 amps?
My wife had the 6400 btu unit cooled her 17x12 room an the
8400 cools the kitchen. dining room and we keep the
temp at 75 F because the temps are close to 100+ here
no need to cool where we are not! I an usually outside with
no a/c working in the heat as I don't like going from 100+ to
75 degrees F when your soaking wet from sweating!

willy

 

[WinterDeere]

How do you figure out example a car battery has 800 cold
cranking amps = how many KWH how to figure this??

Unrelated numbers, like horsepower and fuel tank capacity. Cold cranking amps is how much current the battery can delivery, instantaneously at a specified temperature, the horsepower of this analogy. The kWh or amp-hour (at given voltage) numbers are its capacity, or size of the fuel tank in this analogy.

Deep-cycle batteries may have higher amp-hour numbers with lower CCA capability, versus regular car batteries.