Power and Energy - Watts vs Watt Hours, Energy Cost and Battery Capacity

Watts vs Watt Hours
Amp Hours to Watt Hours

Power is the rate at which electricity is used, energy is the total amount used over a certain period of time.

Includes example calculations for the total energy and cost used, and the capacity of batteries.

[CommercialGasEngineerVideos]

Love how this channel has almost no dead time and you can learn a lot in the time that you spend on it. No waffle or life story business. Straight to teaching.

[ncot_tech]

I like the flowing water analogy for electricity. A lightbulb is a dribble, a kettle is the tap on full.

An EV charging at 150kw - the water main outside in the street after someone has dug through it with a digger, and it's spraying like a fountain.

[DougPaulley]

I am captivated now not just by John and his voice, but by THAT CAT PORTRAIT

[JezCunningham]

I hope the BBC are watching and their people can learn the difference between kW and kWh

[midinotes]

As always John, a brilliant and clear explanation. I wouldn't be surprised if you are doing teaching on the side! I also swear you are getting younger! Lovely to get a video pop-up from you, hope you are keeping well.

[TechOne]

As an electrical engineer, this is an excellent presentation. I have explained this to the young ones over the years in a similarly fashion with exhibits and examples so they really understand the terms. I don’t know what they teach them at college these days. Well done for taking the time to put this up along with the rest of your educational videos.

[Nieldyboy]

Been watch you for years now John. You helped me get through my electrical college qualifications and electrical inspectionand testingcourse, so just wanted to say thanks 👍

[leesholeh]

Great timing! I've been trying to get my head around battery storage & inverters recently. This comes across as clear and easy to understand; maths has never been my strong point. Very helpful, thank you.

[paulsanderson]

Great video clear and concise excellent job John.

[tonymoon]

John, As always your presentation was professional and informative. I thoroughly enjoyed it. Thank you.

[XclubX]

Watt was that?

Yes JW I do have the power to watch your videos, and you have the power to make them.... Keep up the good work

[leybraith]

Thanks, Been using & refining similar water analogy to teach students for years, your explanation gorgeous. Well done.
Looking forward to next in series "determine how much energy things do actually use"

[financelab_ai]

Very useful and straightforward, thanks!

[SN-hxmg]

Nice seen you again Mr John. I hope you will make more videos . Welcome back 🙏

[bill]

John, great show. Even as a power engineer, this was a sweet refresher. It would be a very good topic to do the numbers on electric cars. Also, get a lot of views showing the truth. Topics: Charging times, costs, damage to batteries, temperature effects, etc. So many people have no idea about the costs. My quick analysis showed that my 30mpg car at USA $3.15/gallon gas, did better than the 50 kwh battery in your example, using your .35 pound/kw in England. Don't stop putting up videos. They are appreciated.

[crazygeorgelincoln]

Glad you've lifted the lid on the murkey world of exotic units of battery measurements.
My friend makes electric skateboards with a (huge number)something battery and a 3kW motor (unlikely as it looks like something from a battery drill) whereas my 48v electric bike that mostly gathers dust has a 12 Ah eBay battery and a 1.5kW motor. Trying to make comparisons felt futile at that moment.

[adycee]

Fortunately, most people are like JW.Possessing honesty, integrity & enough intelligence to understanding that buying a new kettle will not reduce the amount of power needed to bring water to 100c.

[uksuperrascal]

Hi JW - @4:58 I did listen and understand your maths as you did explained what you did - But as you wrote 2 / 60 - I question why did you not complete the division 2 / 60 = 0.033 infin 3 OR if the division was not needed why did you write 2 / 60 when you could have used 2 x 3 = 6 to derive your 6 / 60 = 0.1 example, Or at least cross the 60 and kW out to put emphasis on the 2 x 3 .Your maths written description would not make it easy for a lay student to follow if they did not speak English.

[blutey]

Great explanation. Thanks for passing on your knowledge John.
Interesting fact. At rest, the human body generates an average of 100 watts of output ie 100J/s. During sports
activities, it reaches 300 to 400 watts.
So the human body produces nearly as much as heat as an electric throw! (an electric over-blanket).

[silverismoney]

A kettle is a great way of demonstrating power and power over time. They are extremely efficient devices that use a very large amount of power to boil the water, but the total power used is miniscule really. You almost certainly use more electricity cooking something in the 2kW oven than you do making several cups of tea with your 3kW kettle. I also got into the habit of putting my tea/coffee into a thermos flask as I kept microwaving cold coffee which surely is a waste of money.