Daily Archives: August 30, 2011

Albedo 0.39

On average, the earth reflects 39% of incoming energy back into space. To use jargon for no reason other than that I like Vangelis, it has an albedo of 0.39.

Solar farms are springing up around us, incentivised by high feed-in tariffs offered so generously by the UK taxpayer.

I used to be in favour of solar farms but stressed that these should never be built in the UK, but instead in the Sahara desert or somewhere at least a bit sunny. If today’s technology doesn’t allow reasonable cable losses, then we should be waiting till we have super-cables, since there has never been any hurry, even if all the panic about CO2 levels had been correct.

A while back, I had to admit that I was maybe wrong about African solar farms. Having read the book Freakonomics, the authors point out that although solar panels look like a very green solution at first glance, they only produce a small amount of electricity (20% is considered very good for efficiency) but they are also very dark, so absorb a lot more incoming solar energy than the surface did before they were there. For a rooftop, which may have been tiled beforehand, I guess it comes down to the colour and age of the tiles. For a green field in the countryside, not only does it use up land that might have been pretty or arable, it also makes it darker. And for a desert, the change is quite marked. So it isn’t as green as it first appears.

The authors received immediate criticism because they didn’t explicitly compare the waste heat inevitable from alternative production for the same electricity, nor observe that the extra albedo of the panels would vanish once they were removed, but the key point remains true. The accounting for other means of production of the same energy, and comparisons of the overall life-cycle carbon reductions or increases are highly complex functions of the geography and climate at the location of the panel. It is a messy area full or arguments in each direction, as anything to do with climate always is. But, a solar panelled area usually will cause more of the incoming energy to be absorbed, that energy will still enter the earth’s system, and will still cause warming. Albedo might return to normal once the panel is removed, but the accumulated extra heat over its lifetime won’t vanish.

If the doom-mongers were right and warming were a really serious immediate threat and threatened to flip some environmental triggers, then we really should have been avoiding increasing it, even by solar. It would surely be far better to spend the same cash to improve energy efficiency and insulation, both of which would reduce warming, or spend it on extra research, or reducing methane…. And if the feed-in tariffs being offered to solar farmers had been offered to householders to insulate, I am sure most of us would much rather rent out our lofts for extra insulating than have ugly panels attached to the outside or pay a landowner to ruin the countryside. And if we all did that, we’d very soon realise we are all just using our own taxes to pay each other. This policy stinks.

Fortunately, it is a bit irrelevant now we know that warming isn’t as big a problem as the doom-mongers threatened. But yet another case where environmental policy seems a bit daft.

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Face recognition – dangerous stuff?

There are a fair few blogs elsewhere on the potential dangers in face recognition, but here is another one to read.

Several months ago, it was rumoured that Google would add it to their search. Immediately people started to see dangers in it and the potential damage to privacy too. I tend to agree, it is a very dangerous technology. Google decided in the end not to, not yet anyway, but as Google said, even if they are good enough not to introduce it, someone else eventually would, and they were right. Since then, Facebook have been meddling with it, and apparently showed enormous irresponsibility by introducing it without warning users, and without automatically disabling the feature in privacy settings by default. The reaction should have been obvious before they did so, and they were justifiably widely condemned. Keeping it only accessible to ‘friends’ offers little protection, most of us don’t know half our Facebook ‘friends’ anyway. It is just easier to accept friendship than suffer the social embarrassment of admitting you have no idea who that  person is you might or might not have met yesterday. Facebook knows that very well.

Soon, you will be able to use face recognition software to find out who someone is just by pointing your phone camera at them. A quick play on an app and you will also know who they work for, where they live, their contact details, what dating sites they may be on, what they say on their blogs and tweets and even casual comments in forums, whether they are free or in a relationship, how good they are at games, and so on. Face recognition will help link together a great many sites that can’t easily be linked purely via text searches.

Other software may allow it to take account of ageing, so that you could scan in an old photo and check out historic contacts.

I think in many cases, it will be harmless fun, and may make it slightly easier to tag photos on friends on facebook, but the dangers are very high. We can be fairly certain that school-kids would immediately try to track down their teachers to find embarrassing pics they would prefer to keep hidden. We can be fairly sure that people will use it to try to identify people coming into their area, matching them with pictures from previous sex offences, or indeed any other bad behaviour, whether the associated people were found guilty or not. I also have no doubt it will bring an end to many a relationship when people see compromising pics of their partners.

And it won’t be 100% accurate, so a great many people who look a bit like someone who might have been guilty will also get tarnished.  Mis-identification will be as big a problem as correct identification. My photo appears a lot on Google. I haven’t been involved in anything especially embarrassing or naughty. But I have no idea how many people out there have who might look a bit like me, and with whom I might be confused. Some of the photos out already there confuse me with Ian Pearson the ex-government minister even though we look nothing like each other. Proof enough that we can’t assume it will be correct.

It is bad enough being confused with a Labour minister, I certainly don’t want confused with a paedophile or shoplifter or mugger, and for all I know there may well be some that look a bit like me. And even from a marketing perspective, having adverts targeted at me based on my own profile is bad enough, getting ones that are really intended for someone else will be worse still.

I would love to balance this piece as I usually do with enthusiasm for the massive benefits, showing that technology will make our lives better. In this case, the benefits I can think of are all relatively small, and associated with finding criminals or tracking benefits cheats. But they already have enough sense to wear masks  and in any case, heading down that road is far too 1984ish for my taste.