SECTIONAL TRANSACTIONS.— G. 365 



Electricity Act of 1926, embodying the principal recommendations of the Weir Com- 

 mittee, contained such powers. The Act set up the Central Electricity Board, and 

 defines its functions in relation to the Electricity Commissioners. It provides for 

 laying down a national transmission and interconnecting system, and that the Central 

 Electricity Board shodd be responsible for practically all generation by authorised 

 undertakers in Great Britain, though not itself ordinarily acting as a producer. The 

 Act further provides for the selection of those generating stations which are to be 

 retained in operation, arranging for the interconnection of these selected stations 

 and for the gradual standardisation of frequency throughout the country. Some 

 particulars are given of the financial arrangements and of the economies which may 

 be expected from the establishment of such a system. A map is given of the proposed 

 system and of the various sections in which it is gradually being built up. 



The paper goes on to describe the special technical details of the system both as 

 regards the 132 kv. overhead lines, towers, insulators and transformers, and also 

 refers to the subsidiary networks at lower voltage which form an important part of 

 the complete scheme. 



After a reference to wayleaves the author deals with the reasons which led to the 

 establishment of a national system and the technical results which it may be expected 

 to have upon electricity supply in the country. A reference is then made to the 

 influence which the cheapening and spread of electric power supply is likely to have 

 upon the distribution of industries and population, and to the effects which its general 

 adoption for industrial and domestic purposes would have on the atmospheric condi- 

 tions of large towns. 



In conclusion, the author suggests that public opinion has now reached a stage 

 when the appropriate authorities should adopt a more definite policy for a reduction 

 in the amount of fuel burnt in densely populated areas and for a diminution in the 

 number of domestic fires burning ordinary coal. 



{b) Prof. E. W. Marchant. — Limits of the Economical Transmission of 

 Electrical Energy. 



Comparison is first made between the cost of supplying electrical energy from a 

 super station built near a coal mine, using electrical transmission to the centre of 

 distribution, with the cost of supply from a super station built near the centre of 

 distribution and provided with coal by rail transport. When the coal mine is 20 miles 

 from the centre of distribution it is shown that, in England, with stations of about 

 100,000 kw. the electrical transmission of energy by overhead lines similar to the 

 ' grid * costs the same as the transport of coal by rail, when the coal consumption is 

 1'4 lb. per unit. With a smaller coal consumption per unit the electrical transmission 

 would become more expensive, and for larger coal consumption per unit it is relatively 

 less expensive. 



The efiect of difference in the distance of the coal mine from the centre of distribu- 

 tion is next discussed, and with a fuel consumption of 1-5 lb. per unit it is shown that 

 the electrical method is cheaper than rail transport if the distance exceeds 15 miles. 

 The longer the distance the greater the saving due to electrical transmission. 



The influence of load factor is dealt with, and it is shown that improving load 

 factor renders the electrical method of transmitting energy relatively cheaper. 



In the last section of the paper comparison is made between the cost of generating 

 electrical energy in hydroelectric stations and steam stations. For a station of about 

 100,000 kw. and with a 31 per cent, load factor at the centre of distribution, 600 miles 

 away, it is estimated that an expenditure of about £80 per kilowatt is permissible at 

 the hydroelectric station for economical transmission. 



The permissible capital expenditure will be increased with improving load factor, 



(c) Prof. 0. R. Randall. — An Investigation into certain Properties of 

 Insulating Materials using Solid Contacts. 



Friday, August 2. 



Discussion on Roads. 



Joint Discussion with Section I (q.v.) on Problems connected with 

 Deep-mine Ventilation. 



