Modern Gasworks Practice

PLANNING AND LAYING OUT OF GAS WORKS 15 Land required=2',l X3’25 = 6’82, say 7 acres. This will permit of the works being planned with. a view to easy and economical extension, a point of great importance in the works design. Also, more land generally means greater economy in working. In many of the old works which. have grown up from a smaller begin-ning in congested districts the ground area falls very much below that given by the above rule. As an example of this a works hemmed in in the East End of London may be mentioned, where the output per diem is 4 million cubic feet on a ground area of only two acres. Cramped conditions of the kind, however, should be rigor-ously avoided whenever possible. It is interesting to note that twenty years ago the late Mr. A. Colson expressed the view that 2| acres were required per million per day as a minimum. Since tlien the gas-producing capacity of a given area has considerably increased, although tlie remainder of the plant (except gasholders) has undergone very little change so far as necessary ground space is concerned, but ample room is the essential con-dition of efficient working, and it is certainly preferable to work on a basis of 3| acres per million cubic feet. CAPITAL EXPENDITURE The Capital expenditure likely to be entailed in the erection of a gasworks and the equipment of the district is difficu.lt to compute with any degree of accuracy until the site is selected and preliminary survey and estimates have been made. So much depends on the prevailing value of materials of construction, the require-ments of labour, the geographica,! position of the town, facilities for conveying materials to the site, etc., that no hard and fast rule, applicable to all cases, can be given. In preliminary estimates, for parliamentary and other purposes, it is advisable to allow a fair margin to cover possible increases in cost, as the work may be carried out as long as two years after the preparation of the estimate. In the analyses published by the Gas World it is stated that the average Capital employed for fifty-five of the largest undertakings is approximately 12s. Id. per 1,000 cubic feet for Companies, whereas for the undertakings owned by municipal authorities—whicli are somewliat more highly capitalized than the privately-owned concerns—itapproach.es 15s.1 The difference is due to the premiums paid on the transfer of the undertaking to the local authorities. In general, the concerns which. have been promoted in the past for the erection of gasworks and for providing a distributing system have found it possible to com-plete their scheine for approximately £600 per million cubic feet sold per annum, i.e. 12s. per thousand cubic feet sold per annum. In the case of the larger works, the figure was often reduced to £550 or less, but for the smaller country works the outlay has been considerably greater, a normal figure being £750 to £1,000 per million cubic feet sold, according to size. At the present day it is seldom that a large town is required to be fitted out with a complete gasworks and supply system; and, consequently, it is the figures 1 Original Capital employed irrespective of later reductions by Ioan repayment, etc.