Friday, May 8, 2009

More or Less - the Director's Cut

I was on "More or Less"a couple of weeks ago, and wrote an article for the BBC. One topic mentioned was how much good it does to unplug phone-chargers when they are not in use.

On today's programme (8 May 2009) they are going to read out an indignant listener's letter pointing out that "if everyone unplugs their phone chargers, it adds up to a HUGE saving". More or Less asked me to write a short response, which is going out today. I'm worried that people will get the impression I am against switching anything off. So for the record, I would like to point anyone who's interested to the relevant pages of my book (p114) and Chapter 22 (p155) which should make clear that I do think that it's a good idea to find the big vampires and switch them off!
Here's what I wrote for today's More or Less, in full:
Yes, if sixty million people all make a figleaf gesture that saves half a watt (which is roughly one ten thousandth of their power consumption), then the total power saved is,
sixty million times half a watt
which is 30 megawatts, which sounds like quite a lot. It's one thirtieth of the output of a modern power station, for example. But this "if-everyone" multiplying machine is just a misleading way of making something tiny sound big:
30 megawatts is still just one ten thousandth of Britain's total power consumption.
Multiplying tiny things by sixty million to make them sound big is BAD because it distracts people from thinking about sixty million bigger things that are more deserving of our attention. [Heating sixty million buildings, and driving sixty million cars, for example.]

5 comments:

Andrew Sherman said...

Hi David, I love your book and thanks for all the work you are doing on this subject. I am not sure your answer is the best way to deal with the indignant listener. Yes your numbers add up and are logically correct, but will they persuade intransigent listener? I think you need to compare the small effect of unplugging phone chargers with some other small effect. Saving half a watt for 24 hours is the same as switching off a 40 watt bulb for 18 minutes a day (is that right?). So if you turn off the light in the kitchen while you watch TV you will save far more power.

David MacKay FRS said...

@Andrew, agreed - yes, everything must be compared with something sensible. But they wanted a very short response, and they cut out the (rather vague) comparison I had in my longer response, which compared with buildings and with cars. "Multiplying tiny things by sixty million to make them sound big is BAD because it distracts people from thinking about sixty million bigger things that are more deserving of our attention. [Heating sixty million buildings, and driving sixty million cars, for example.]"

Annz said...

I heard most of this by accident this afternoon, and thought it was generally positive. Andrew is right that comparing like with like is a good tactic, but no one approach will convince everyone.

The opportunity such a letter provides, to respond to it, is really a golden opportunity.

Not everyone who listens to More or Less will hear every episode. The letter gave an opportunity for your message to reach a wider audience. Not just any audience, but, even better, one more likely than not to be comfortable with numbers. It also provided an opportunity to follow up via the More or Less website, with links to the previous programme and the shorter pieces you have now written (which are really good) as well as your book.

Tim Harford's wry comment, to the effect that More or Less had probably not quite got 60 million listeners yet, did add an important touch of humour to the piece.

Brian O' Hanlon said...

David,

I listened with great interest to your presentation in Dublin today. Thanks for making the journey and giving a great talk. I am a very young and inexperienced student of eco-friendliness matters myself. But from time to time, I do a quick blog. I think it helps me to push the boundaries of my own thinking a little bit. You are welcome to read my post here if you find the time:

http://designcomment.blogspot.com/2009/05/on-standby.html

I hope to get through reading your book this summer for sure. Totally unrelated, but a person linked a rare Marshall McLuhan audio recording in their response to my blog here:

http://designcomment.blogspot.com/2009/03/on-mcluhans-legacy.html

It's a real treat, and discusses a lot the sociological relationship that Americans have to the outdoors.

Thankyou again.

Brian O' Hanlon

Brian O' Hanlon said...

Vampires simply refusing to go away,... this time it is the American's turn.

http://green.yahoo.com/blog/the_conscious_consumer/75/vampire-power-costs.html