The terrifying scale of the green revolution
Many have been emotionally drawn to the green revolution in
the belief that renewable energy will restore our personal and community independence. According to this, by investing in green technology, Britain will gain freedom from coal barons and gouging sheikhs, and deliver a grass-roots, democratic energy system. Ed Miliband played into this on Friday when he blamed the energy price cap being raised on the ‘failed energy policy we inherited, which has left our country at the mercy of international gas markets controlled by dictators.’
Others believe green energy represents the free spirit and harmony with nature. ‘What would you rather have in your neighbourhood?’, I remember being asked in 2005. ‘A little wind turbine swirling gently in the breeze, or a nuclear power station and pylons?’
The low energy density of wind and sun means that extremely large collection devices are needed
As it is turning out, and particularly so now that Ed Miliband is back in charge of energy policy after 14 years in the wilderness, the green transition means armies of gargantuan wind turbines on land and sea; great blue-black mirror of solar panels glazing over thousands of acres of farmland; a neurotic spider’s web of grid cables criss-crossing the country; and dozens and dozens of whining substations and vast Area 51-like compounds of shipping-container sized lithium-ion batteries.
As if that were not bad enough, it transpires that in spite of all this green industrialisation we will still require nuclear and conventional gas turbine power stations. We may not use them as much, but reliability is an issue with wind and solar, and therefore generators are needed to guarantee security of supply at times when the British weather fails to deliver. ‘Who knew, except everyone?’ as the Americans say.
Still, the sheer immensity of low carbon industrialisation is coming as an unwelcome shock to those who only a few years ago would have at least passively supported wind and solar development.
There was clearly a profound misunderstanding about the physical character of renewable energy power systems. But no one should in fact be surprised. The physics of renewable energy are inescapable.
While there is a substantial quantity of energy in the wind, the thermodynamic quality of that energy is very low. It is for this reason that there are no organisms that derive their metabolic energy from wind, an extraordinary fact given its widespread availability at unthreatening temperatures. Wind energy is simply too chaotic to support life.
Solar radiation is somewhat better. Indeed, outside the earth’s atmosphere it is of fairly high quality. But on the surface of the planet and seen from the perspective of a leaf or a photovoltaic cell it is hindered by atmospheric interference, clouds and airborne dust, and critically by the rotation of the earth. Plants do derive energy from sunshine, but they are relatively simple organisms, and they do not move rapidly or have complex nervous systems.
Some aspects of these simple facts about wind and solar energy flows are intuitively obvious but the critical implications tend to escape even those well versed in physics.
The low energy density of wind and sun means that extremely large collection devices are needed – enormous wind turbines with large blades, vast areas of solar panels. It is necessarily a capital-intensive and very expensive system.
A concrete example will make this clear. The 1,400 Megawatts (MW) Sophia Offshore Wind Farm on the Dogger Bank is currently under construction and will cover an area of nearly 600 square kilometres (it would just about fit into Middlesex). It is one of many major wind installations that the government is intending to drive through in its ambition to quadruple offshore capacity. We currently produce about 15 Gigawatts (GW) of operational offshore wind power. To meet this quadrupling of capacity, we would need around 30 more Sophia Offshore wind farms.
The Sophia will use the Siemens Gamesa SG 14-222 DD, one of the largest wind turbines on the market, with a generating capacity of 14 MW. It has three blades 108m in length, each weighing 65 tonnes. The nacelle, the box containing the generator at the top of the tower, weighs 500 tonnes, which Siemens proudly describes as a lightweight machine. Compared to other brands, this may even be true.
The overall height of the turbine is 252m, only 60m short of Britain’s tallest building, the Shard. It foundations will, according to Sophia’s own publicity, be 80 to 90m in length and weigh 1,200 to 1,400 tonnes each. The total weight of each turbine – blades, nacelle, tower and foundations – is likely to be nudging towards 3,000 tonnes.
Sofia will use 100 of these structures, so we can estimate that the wind farm alone accounts for about 300,000 tonnes of industrial equipment, mostly steel, some concrete, and fibre-glass reinforced epoxy in the blades. (For reference, a Queen Elizabeth class aircraft carrier weighs a mere 65,000 tonnes.) And this is before we have taken into account the offshore substations and the cables connecting each turbine and the shoreline.
Multiply all this by 30 to meet the government’s offshore wind targets, and you arrive at nine million tons of industrial equipment for the additional offshore installations alone. For scale, recall that the UK’s total annual production of steel is only six million tons, and you can begin to appreciate the magnitude of Ed Miliband’s plans for the country. This Wind and Sun King makes Louis XIV lookhumble.
The total manufacturing mass involved in Sophia is difficult for anyone outside the project to calculate, but the order of magnitude is clear: it’s huge, and regardless of your views on its beauty, it’s certainly not going to be cheap. Sophia states that its total capital cost is in the region of £3 billion, a great deal for an asset exposed to the North Sea and likely to have a short economic lifetime.
Onshore wind farms weigh less than Sophia’s marine leviathans but are of broadly similar dimensions. The Vestas V136 4.2 MW, for example, has blades of 76m and hub heights up to 166m, giving a total overall height of over 240m. The Eiffel Tower is only 60 meters taller. These are the sorts of devices that Ed Miliband now thinks acceptable next to rural dwellings.
But relative to their size, these wind farms do not produce much energy. Sophia, for example, will produce around six Terawatt hours (TWh) per year, according to the company’s website. Although this is unlikely to be maintained over the entire lifetime of the windfarm, this is still only equivalent to about 2 per cent of total annual UK demand for electricity. Given the sheer size of Sophia that really isn’t very much – only around 0.01 TWh per square kilometre.
Solar, as predicted from theory, is slightly better, but still abysmal. Mr Miliband recently overruled the recommendations of his own planning inspectors to consent to a 500 MW photovoltaic installation on 2,500 acres (10 square kilometres) of Suffolk farmland near Newmarket. It is about 15 miles long, and comprises around one million solar panels. In spite of the site’s gross magnitude, it will generate only about 0.5 TWh of electrical energy per year. This is a very poor exchange for the energy or food that could be otherwise grown on the land.
For comparison, consider the Sizewell B nuclear power station, also in Suffolk, and running since 1995. The site occupies a land area of about 0.5 square kilometres, less than a thousandth of Sophia’s area. Still, Sizewell B generates more energy, as much as 10 TWh a year. It is, very roughly, 1,500 times more productive than the Sophia wind farm, and 300 times more productive than the Sunnica solar farm when it comes to space. On this land use basis, Sizewell C, now under construction, can plausibly claim to be 1,000 times more productive than solar and 3,000 times more so than onshore wind.
That is typical for conventional power stations: they are small and highly productive compared to renewables. Correcting the severe physical defects of wind and solar generation requires capital equipment on the grandest of scales, and as a result the adoption of renewables results in a low productivity system which is intrinsically expensive and resource hungry compared to the fossil and nuclear alternatives.
Moreover, most of the extraction, conversion and delivery of renewables is at present manufactured by a fossil-fuelled global economy – primarily in Asia and in particular China.
But if, as the government seems to want, green equipment is produced domestically, then the costs will rise dramatically. In this case, is not even clear that there would enough of an energy return to justify the costs of a wind or solar project. The profit margin would be very thin, or even non-existent. At best, the renewable energy sector would not only be the largest consumer of its own energy output, but encompass the bulk of the British economy. Those owning green energy businesses would possess levels of relative wealth and power not seen since the gentry and aristocracy of the pre-coal economies of Europe. One imagines that this would be politically extremely controversial.
So, there is more to the industrial dystopia of wind turbines and solar farms than mere aesthetics and a counterproductive climate policy.
