Generally Speaking

My comparison of the brightness of different kinds of light-bulb.

Two days ago I tweeted a contribution to the upcoming 10:10 forum on LED lighting:

@1010 We have two LED bulbs billed as 60W replacements by Homebase which are much brighter than 100W

When this provoked some interest I added that I had kept meaning to test this impression by using the light meter of my camera.  10:10 replied that they would be interested in the results. So, waiting only for darkness to descend, I went ahead with my simple experiment. Which confirmed my assertion, thus:



IMG_20140211_190935Lumix G2 camera set on Aperture Priority mode.  Sensitivity at ASA 1600  Aperture fixed at f3.6

Night time. No other light sources present.

The only change made between each reading was the  bulb itself.

The two mini fluorescent examples were allowed to warm up to full intensity before taking their readings.


  • 60 Watt Incandescent:      1/60th second exposure required*
  • 100 Watt Incandescent:    1/100th second exposure required*
  • 15 Watt mini-fluorescent:   1/100th second exposure required*
  • 12 Watt LED:   1/160th second exposure required*
  • 30 Watt mini-fluorescent:   1/200th second exposure required*

*The amount of light produced by the bulb is presumably in inverse proportion to the length of the exposure required – i.e. the shorter the exposure the brighter the bulb.


These results suggest that while the 30W mini-fluorescent is the brightest bulb tested, the 12 Watt LED bulb bought from Homebase produces nearly three times as much light as the 60 Watt incandescent bulb for which it was billed as a replacement, and is more than half as bright again as the 100 Watt example, just as I claimed in my tweet.


One factor inhibiting people from changing over to LED lighting in their homes (apart from the cost – which is falling dramatically) is the belief that you can’t really get an adequate replacement for a standard 100Watt light bulb. Homebase, at least, appears to be contributing to this misconception by underselling the particular LED bulb which I used in this comparison.

I had no means of testing the accuracy of the wattage marked on the different bulbs, but if these are roughly correct then this experiment also supports the commonly repeated claim that LED bulbs use approximately 1/10th the electricity for the same light output.

I can feel further blogs coming on re:

  • The emerging practicality of large-scale changeover to much more efficient means of domestic lighting
  • The enduring validity of amateur experimentation, even in cutting-edge areas.

Who is the most dangerous of all… ?

Letters to the Guardian are not available online so I have taken the liberty of copying and posting one which is in today’s paper under the heading Fantasies shaping children’s futures :
“If what you want is to understand Michael Gove as a public figure in charge of the nation’s educational needs, there is little point in debating what he might call his “ideas” (Letters, 4 February). One needs rather to focus on three things. First, and notwithstanding the acquired, but now melting, patina of Oxford cleverness, his manifest stupidity, apparently incorrigible. Only an idiot could seriously maintain that a day will come, causally engineered by none other than Michael Gove himself, when it will be impossible to distinguish state schools from fee-paying schools – a deft account of the sheer idiocy of this view is provided by Peter Wilby (Comment, 4 February).“Second, his fantasy life, that of a man lost in translation between past and present, and more precisely the fantasy, bordering on obsession, of the arriviste, wannabe toff drooling over the lexicon of long ago while dreaming of the glory days of “prep” and “lines”. Third, the political ambition. Despite all the guff about linking educational “standards” and “social mobility”, everything that Gove does as secretary of state for education serves a very precise purpose. Gove wants to be the next leader of the Tory party and one day perhaps prime minister.

“How do you use the education brief to best serve that end? By playing to the Tory right and making an educational offer to those sections of the electorate which, in the context of recession, no longer feel able to afford private education for their children. It is only a matter of time before the sharp-elbow classes swamp the academies and the free schools. Reintroducing the “common entrance” exam at 13 (another of the terms in the vocabulary of Gove’s regressive fantasy life; the common entrance, I ask you!) will seal the deal on that front.

“The rest is dross. Gove is not only the silliest member of the government; given that his compulsions and ambitions are currently shaping the future of millions of children, he is also the most dangerous. The priority has surely to be not debating him, but getting rid of him.

Professor Christopher Prendergast
King’s College, Cambridge
And this is the letter I have just submitted in response:
Professor Prendergast finishes his otherwise superb letter (6 February) by suggesting that Michael Gove is the most dangerous member of the government. The competition is hot and the bar is high but the Secretary of State for the Environment, Owen Patterson, is surely far more dangerous. Yet even so the ultimate prize must go to the man who appointed such a known global warming denier to such a crucial position at such a crucial time.
J A R Willis

Once More with Feeling anniversary

It is now a year since my climate change meeting in Alton Assembly Rooms. That means another year has slipped by since the talk which I had given seven years before that, which I felt compelled to repeat because its message was still so true, so urgent, and because so little had been done.

An astonishing turnout
An astonishing turnout

The talk I booked the hall to give again a year ago, with no inkling of the amazing number of people who would come to hear it on that wet winter evening, was my opening keynote address to, of all unlikely events, the 2006 North European Travel Medicine Conference. And by a curious chance, the day on which I gave that address in the Edinburgh International Conference Centre happened to be the day on which our youngest grandchild was born.

I had been asked to give that address out of the blue simply because one of my regular columns in the medical press the year before, 2005, had been on the subject of climate change denial. The organiser of the scientific programme had read that article and must have realised the subject would be a suitably important opening for his conference. But I had certainly not written the column as an expert on climate change. Far from it. I wrote it, and I gave my address, from the point of view of a responsible, informed citizen whose background in medical science had taught him to tell the difference between ‘reliable knowledge’ and its opposite.

In this winter of floods, with the climate change denial industry itself in full spate, the cartoon which The New Generalist  commissioned all those years ago to illustrate my article seems astonishingly apt today:

Cartoon commissioned by the New Generalist to illustrate my 2005 Climate Change article
Cartoon commissioned by the New Generalist to illustrate my 2005 Climate Change article

One year on from Once More with Feeling, the most tangible outcome (apart from the gratifyingly-complete cessation of climate change denying letters in the Alton Herald) was to look at the kind of language being used when we try to decide which of the two stories about climate change we can trust. For there are  two stories and they can’t both be right!


The first sign we looked at last year was vitriol, and I gave quite enough sickening examples of that to show the difference between denialist abuse and trustworthy scientific discourse.


The second sign is certainty. Science is never certain, and this fact has been exploited and misinterpreted over many years by the deniers of a whole range of scientific concerns, from the link between smoking and disease, through the link between CFCs and the ozone hole, to our present concerns about global warming (this is detailed in Merchants of Doubt). But what science can tell us is when the available evidence has taken us far beyond the point at which it is absolutely necessary to take avoiding action. As I said a year ago, sensible drivers hit the brake before they hit the wall, especially when they’ve got a car full of children.

The new thing I would like to add in this update, which I am sending to my whole follow-up list because I have been so warmly encouraged to do so, goes rather along the same lines:

I suggest imagining that you ask James Delingpole, to take one of the high-profile deniers at random, although it could be Nigel Lawson, or Jeremy Clarkson, or Melanie Phillips, to tell us their level of certainty that they are right and that the scientists are wrong.

Are they, perhaps, absolutely certain that the warnings of, say, the Intergovernmental Panel on Climate Change can be scornfully ignored? If they say that they are indeed absolutely certain, then they automatically disqualify themselves from serious discussion – they are talking faith, not science. By definition.

But if they admit that they do have some doubt, then imagine asking them to say what that level of doubt would have to be before they stopped expecting you to back their pollyanna bet on the future of the world. And if that sounds like a check-mate, that is exactly what it is. These people with their reckless message have long outstayed their welcome. It is high time to recognise the damage they are doing and finally face them down.

Today’s news includes the halting of the Australian Open tennis championship because of extreme temperatures, after a summer in that continent which broke all records by a margin. Another item in today’s paper is about a report, from BP of all people, saying that greenhouse gases are set to rise 29% by 2035 and that fracking isn’t going to help. “The Intergovernmental Panel on Climate Change says that emissions must peak by 2020 to give the world a chance to avoid a further two degrees of warming, beyond which the effects of climate change become catastrophic and irreversible.”  The climate changes which are affecting us all today and which are the subject of so much concern have resulted from less than one degree of warming so far. Do the math, as they say, if you dare.

When I wrote my article eight years ago it seemed to me inevitable that the world was waking up and that remedial action was about to be taken. If only. We cannot wait any longer. Ordinary people must create a climate of opinion in which it is not only possible for politicians to take the necessary actions, but impossible for them not to. As one fossil fuel company, BP, has apparently realised, this is one area where we really are ‘all in it together’.

That is why I make no apologies for this email. ‘Retirement’ is a funny thing, because I can’t help feeling that the meeting a year ago today, long after I retired from my wonderful life as a doctor, may have been the most important thing I have ever done.

Imagine if Owen Paterson had been lobbied by ‘asbestos deniers’

Imagine if UK Secretary of State for the Environment Owen Paterson had been approached by lobbyists employed by the asbestos industry telling him that the science linking asbestos inhalation and the particularly nasty kind of lung cancer called mesothelioma was in doubt. And that all the scientists and scientific institutions who were currently claiming that there was such a link were conspiring to deceive the public so as to justify ideologically-based restrictions on personal freedom which would result in increased taxation…
In that case, how certain would Owen Paterson have to be that this view of the situation was right before he began to inhale asbestos dust himself?
And how certain would Owen Paterson have to be that all the scientists were wrong before he began to use his position as UK Secretary of State for the Environment to undermine moves to control the release of asbestos into the environment so that children began to inhale it too?
And, last but not least, how confident of this position would Owen Paterson have to be before announcing to a fringe meeting of the Conservative party conference that asbestos exposure “can have a positive side” and that “People get very emotional about this subject and I think we should just accept that [asbestos exposure has been going on] for centuries”?
Now, to return to the real world: How likely does Owen Paterson think it is that fossil-fuel lobbyists are wrong when they deny the validity of the scientific evidence concerning the threat posed by man-made global warming?
Nobody fit to hold a position of responsibility can ever take the view that there is no chance at all of their being wrong about a controversial issue, that is a truism. So has Owen Paterson contemplated the seriousness of the consequences if he is wrong about the issue of man-made global warming – in fact the possibility that he has been deceived by the lobbyists – however small he may think that possibility may be?   If not, could we all encourage him, please, to contemplate the seriousness of those consequences now.


The age of foolishness

A key change in the ‘new way of doing things’ is a wholesale substitution of externally-imposed rules for personal judgement and common sense. This is not so much a tyranny by the arbitrarily powerful as an abdication of responsibility in which we all are complicit.

This dutiful subservience to rules gives us a seductive excuse for abandoning the immensely difficult task of building up and then maintaining throughout life a soundly-based personal understanding of the way the world works. This is particularly true in the fields of technology and science, which are now deemed by many, if not most people, to be too advanced and abstruse for non-specialists to even attempt to understand. Thus, at a time of unprecedented freedom of access to information we have the perverse phenomenon of people everywhere, and at all levels of society, actually making a virtue of ignorance. And in consequence we are seeing everywhere, and at all levels of  intelligence, the fatuous certainty which is normally characteristic of  the very stupid. Nowhere is this more starkly and terrifyingly apparent than in the organised denial of the science of evolution and climate change which has become the orthodoxy throughout the immensely powerful American Republican party.

It is my instinctive recognition of this looming problem – and heaven knows where it came from – that has underlain my opposition to the systematisation of professionalism (for example in the form of blind subservience to ‘Evidence Based Medicine‘) which has dominated my career and motivated me to write my two books, numerous articles, and to give so many ineffectual lectures.

Climate Surfing – a selection of links

We tuned up the following list of links during our recent Climate Week 2013 event.
I’m posting it here in case it is useful to anyone else.
Concern about Climate Change
Answering Denial
Ways forward

Saving energy

Wind Power

Tidal Power

  • Sea Gen – Sea Generation Tidal Turbine (1min)

Solar Power

  •  A Shade Greener A short video by the BBC explaining the benefits of Free Solar Panels: 

What can We do?

  • * Reality Drop: Makes it easy to help ‘Spread Science about Climate Change, Global Warming’

The Climate Week Declaration

Climate Week 2013 starts tomorrow and I have just signed the Climate Week Declaration. Here is the full wording.

Britain must do all it can to create a secure, prosperous and sustainable future by helping to prevent climate change.

We call on the government to maintain its commitment to the Climate Change Act by taking further steps to encourage investment in the green economy, greater use of renewable energy and positive action across society.

The Energy Bill currently being considered in Parliament is an important and urgent example of the commitment needed. We urge the government to act on the recommendation from its own Committee on Climate Change to include decarbonisation targets in the Energy Bill.

And I got the nice badge to prove it:Print

Now I’m seeing if my colleagues on the Alton Society committee will agree to us signing up as a body. STOP PRESS: Yes they have, with enthusiasm!

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