The Battle of the Pylons
JOHN MADDOX writes:
Ever since the mid-Thirties, British electrical engineers have been proud of their lines of steel pylons. For most of that time they have been well aware that the National Grid was the envy of their colleagues abroad.
Even now, a great many industrialised nations have not been able to develop a system as effective as that which the Central Electricity Board operated before it conceived of the new 400 kV lines. Whatever disputes there may be about the technical virtues of British aircraft, or British ships, there is no question that the British grid is a lesson to the world. It is no wonder that the men who built it should feel they are being cruelly injured by the storm now raging about the lines chosen for the newest cables. They tend to think of themselves as prophets without honour in their own country.
There is an overwhelming technical and economic case for a National Grid, and a Super- grid, and a Supersupergrid. That is not in dispute. By linking all the country's power stations to the same system of high voltage cables, it can be arranged that as much as possible of the country's electricity is produced in the most efficient power stations. Nobody seems to have put a figure on the money thus saved, but it must be an enormous sum. Simply because the grid exists, it is possible to run almost continu- ously the huge modern power stations in the cheap coalfields, which can produce electricity for a mere halfpenny a unit. The cost of elec- tricity would inevitably be greater if more use had to be made of the older power stations up and down the country.
Since the war, however, the grid has been not merely a financial economy, but an essential part of the strategy of electricity production. In the Fifties, for example, the electricity auth- orities held to the simple argument that it was cheaper to transport electricity by wire than the corresponding amount of coal by train": Accord- ingly they built a string of power stations along the valley of the Trent, each of them intended to be a major supplier of electricity to the south of England. At night, when the demand for electricity is lowest, virtually all the country's electricity may be produced from this group of power stations.
Thus the grid is now a necessary paff of the electricity economy. To abolish it would not merely be expensive; in present circumstances, it would be impracticable. And it follows that the waves of protest about the 400 kV lines which the CEGB now wishes to erect will, if they are heeded, substantially affect the pattern of elec- tricity distribution.
There is little hope that technology will make things easier for the CEGB. Though pylons would be smaller if electricity were distributed as direct and not alternating current, the dif- ficulties and the costs of turning one form into another are still formidable. The industry seems to be following this line of research without hope of immediate relief from the pressures which assail it.
More immediately, there seems to be a solid core of truth in what the CEGB says about the great cost of burying high-voltage cables in the ground. A mile of 400 kV pylons and their cable costs roughly £50,000 and Sir Christopher Hinton says a mile of underground cable would cost More than twenty times as much. In tech-
nical terms, this discrepancy is entirely credible. Burying a high-voltage cable is not simply a matter of digging a ditch. The difficulty is to insulate it properly. The great technical virtue of a pylon is that mere height will provide twenty to thirty feet of air insulation.
What, then, is to be done? And is it really necessary to make a choice between pylons on the South Downs and electricity costing perhaps 10 or 20 per cent more than it does at present? These and the other issues which arise are to be judged in the certain knowledge that the country's consumption of electricity will double in the decade ahead just as it has doubled in every decade for the last half-century. If things go on as they have been doing,. by the mid- Seventies people may be up in arms about still larger pylons on the edges of national parks.
Fortunately, the choice between dear elec- tricity and unspoiled amenities need not be nearly as sharp as it has become. Some of the headlong conflicts between- the CEGB and the defenders of amenities might be avoided, or at least softened, by better administration of the machinery for giving public consent to the con- struction of power stations and pylons. At present, the CEGB tends to apply for permission to build a power station without specifying the details of where the pylons will run. Only later may it become apparent that some piece of parkland may have to take a pylon or two before the power station can work properly.
The same piecemeal way of dealing with the routes of high-voltage lines does often imply that the community at large has no opportunity of advocating a major revision. Yet it must very _often be the case that the cause of amenity could be safeguarded in important ways by shifting a proposed route by up to five or ten miles along most of its length. Simply because the 400 kV lines are strategic rather than tactical in their conception, the precise details of their routes are relatively unimportant, while the cost of a large diversion, at £50,000 a mile, could be proportionately quite small.
Simply because the grid has become such an important element in the strategy of electricity generation in Britain, power stations tend to be sited in such a way that a further development of the grid becomes essential. But especially with the enormous growth of electricity consumption in the bigger cities, there might be virtues in a system in which more modern power stations were built to serve the needs of their localities.
In the long run, what the country needs is a more effective way of striking balances as delicate as these. In some places, it would be considered better to pay a little more for electric- ity and to have a small power station on the edge
of a city, than to run pylons through national park. Elsewhere the balance might be struck the other way. In London, for example, there are many people who would pay a sub- stantial price for ridding Battersea of its power station. What is lacking in the present arrange- ments is some mechanism for striking a balance between amenity and efficiency at the level (A strategy, not that of tactics.
Previous page
