Fakes and facts

According to Wikipedia:

A significant amount of fraudulent news during the 2016 United States election cycle came from adolescent youths in Macedonia attempting to rapidly profit from those believing their falsehoods.

And when the BBC sent a reporter to the town of Veles Macedonia she found the streets lined with new cars and motor bikes and the bars packed with grinning youngsters who had made a killing by promoting this ‘clickbait’ on Facebook.

And there was I wondering how Jacob managed to afford that big, flash, vintage Rover with the personalised number plates.

Meanwhile, I read on the Website Nautil.us that fake science journals are publishing fake research by fake scientists with names like Hoss Cartwright and Borat Sagdiyev.

But how do we know that this story isn’t itself a fake?

Interestingly, the Oxford English Dictionary has just nominated “Post-truth: relating to or denoting circumstances in which objective facts are less influential in shaping public opinion than appeals to emotion and personal belief”, as its new word of the year.

As someone said recently: “The truth is whatever a majority can be persuaded to believe. The facts are another matter altogether.”

The BBC has an excellent programme – More or Less – which takes some of the numbers that have featured in the news and tests them for accuracy.

This week’s programme discussed Greenpeace’s claim that, last year, for the first time, the world’s renewable energy electricity generation capacity edged ahead that of coal, and, as coal is the greatest source of Carbon Dioxide; described during the programme as the “most significant greenhouse gas”, this is good news in terms of climate change.

This claim is actually true, but, when you look at it more carefully, it is also misleading.

Tim Harford the show’s presenter, who is an exceedingly smart cookie, wanted to know how these capacity figures compared with the actual amount of electricity produced. His researcher explained that the International Energy Authority’s definition referred to the nameplate capacity i.e. the amount the device can produce when running flat out.

But the wind doesn’t always blow or the sun shine Harford observed, so what is the actual output?

It turned out that coal only ran at full tilt 50% of the time and renewables 30%, with the result that coal produced 40% of the world’s total compared to 23% for renewables.

That’s almost double, but in fact the differential is rather more dramatic because here I think Tim Harvard fell below his own high standards when he said the reasons why coal only ran at half its maximum was because of maintenance shut downs, low demand and carbon emission targets.

And, while closing a coal plant for maintenance is obviously essential, the other two reasons are voluntary – contrast with the the no wind, no sun scenario.

So coal plants have the potential to run at 80% capacity while the constraints on renewables make it impossible to exceed the present 30%.

Coal’s capacity factors are depressed by the fact that wind and sun have privileged access to the grid i.e. if the power is produced, the grid has to take it.

That means on windy, sunny days coal has to be ramped down with the result that consumers are paying subsidies to wealthy landowners with renewables while at the same time compensating the owners of the coal-fired stations to maintain what is known as “spinning reserve” in case the weather conditions change.

For the record, on this cold November morning, CEGB’s website gridwatch templar shows our huge fleet of wind turbines contributing just over 3% of the nation’s requirements.

It should also be noted that, while talk of renewables conjures up images of wind turbines and solar panels, by far the biggest contributor to this class of generation is hydro-electric, some of which (e.g. Hoover Dam) have been around for the best part of a hundred years.

Indeed, with present technology, hydro-power which, unlike wind and sun, has the advantage of being available on demand, is by far the most efficient form of renewable power generation, though with good reason – displacement of people and loss of habitat among them – almost all big dam developments are opposed by environmentalists.

Finally, the statement that Carbon Dioxide is “the most significant greenhouse gas” is not true.

That accolade goes to water vapour which contributes an average of 70% of the greenhouse effect. Indeed it is nothing to do with greenhouses which trap heat by reducing convection losses.

So-called greenhouse gasses operate by absorbing and re-emitting outgoing infrared radiation of certain wavelengths (see this simple animation) which is an altogether different physical process than that which keeps your tomatoes warm.

Some of this is re-emitted back towards earth causing causing the atmosphere to warm up.

This characteristic of gases with three or more atoms (CO2, H2O, Methane (CH4) etc) is not shared with the diatomic gases O2 and N2 which make up 99% of the atmosphere.