Can you make sense of energy? This may help!

I found this video yesterday looking for a way of understanding energy. It was made by Prof. David MacKay, Professor of Natural Philosophy in the Department of Physics of Cambridge University and author of the book ‘Without the hot air‘, that I suggest everybody to read, or at least have a look, to understand better the inter-related issues of climate change [and you can download it for free here!!]. 

Anyway, although I don’t agree with him for everything he says. The emphasis on nuclear power to solve our energy crisis is not for me, but I agree with him in many other concepts.

But what I found spectacular is the fact that he expresses all the energy he uses with a unique measure: a lightbulb!!! And it is something all of us can make sense of, can’t we? We use them everyday, so when he tells us how much energy a bath use in comparison of the energy used by a light bulbs being on all day it does make sense to me. At list I can represent the concept in my mind!

So let’s start!!

This is our baseline. One 40 watts light bulb on for 24 hours consumes 1kWh per day.

If we take one hot bath a day, we will consume the same energy used by 5 light bulbs on for 24 hours.

Image source: Julia Soderberg, from The Noun Project

Heating an average British house during winter for a day consumes the same amount of energy used by 40 light bulbs that have been on all day.

The same amount of energy is used to drive 50 km in an average car: 40 light bulbs on all day.

If we sum up all the activities we do everyday we achieve the result that the average British citizen use the same energy of 125 light bulbs that have been on all day.

If we then multiply that results for the 60 millions UK citizens we obtain a number that is not even conceivable for me…. 125 light bulbs per person multiplied 60 millions….. 7.5 billions of light bulbs? A day? Only for UK? Yep, look like that!!

Even energy is nice when you look at it from this point of view… Don’t you think?!

Ciao ciao! m.



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