| A.T.—ALTERNATING TRANSFORMER DISTRIBUTION. | |
| Generating station, buildings, chimney shaft, | £ |
| water tanks, and general fittings | 11,000 |
| Dynamos and exciters—865 kilowatts, including | |
| spare sets, divided as convenient | 5,540 |
| Motive power, i.e., engines, boilers, steam and | |
| feed connections, belts, &c., at £8 12 s. per I.H.P. | 12,470 |
| 500 transformers, i.e., one to every pair of houses, at £15 each | 7,500 |
| 2,000 yards primary or charging main, exterior | |
| to area of supply, at £308 per 100 yards | 6,160 |
| 20,000 yards distributing main, 50 mm. sectional | |
| area, at £91 7 s. (see [Table I].) | 14,270 |
| Regulating gear | 500 |
| £ 57,440 | |
| B.T.—ACCUMULATOR TRANSFORMER DISTRIBUTION. | |
| Generating station, buildings, chimney stack, | £ |
| water tanks, and general fittings | 8,000 |
| Dynamos—600 kilowatts, in six sets of 100 kilowatts each | 4,800 |
| Motive power, i.e., engines, boilers, steam and | |
| feed connections, &c., at £8 12 s. per I.H.P. | 8,600 |
| 4 groups of accumulators, in all 240 cells, in | |
| series, at £40 per cell, including stands | 9,600 |
| 2,000 yards charging main, at £306 17 s. 6 d. | |
| per 100 yards ([see Table II].) | 6,137 |
| 20,000 yards distributing main, 161·25 mm. sectional | |
| area, at £100 12 s. 6 d. ([see Table II].) | 20,125 |
| Regulating gear | 2,500 |
| £ 59,762 | |
Table IV.
Working Expenses and Maintenance of 10,000-Light, or 600-Kilowatt, Plant.
| Direct Alternating Transformer System. | ||||||
|---|---|---|---|---|---|---|
| Materials— | £ | s. | d. | £ | s. | d. |
| Coals: 4,380 tons at 17s. | 3,723 | 0 | 0 | |||
| ” 2,550 ”17s. | · · | |||||
| Oil, water, and petty stores: | ||||||
| 1,500 hours at 7 s. 6 d. | ||||||
| 7,250 hours at 1 s. | 925 | 0 | 0 | |||
| 1,400 hours at 5 s. | · · | |||||
| Total cost of material | 4,648 | 0 | 0 | |||
| Labour— | ||||||
| 2 foreman drivers at 45 s.; 6 drivers at 30 s.; | ||||||
| 9 firemen at 24 s.; sundry labour | ||||||
| 1 foreman driver at 45 s.; 2 drivers at 30 s.; | ||||||
| 3 firemen at 24 s.; sundry labour | 1,388 | 8 | 0 | |||
| Salaries— | ||||||
| 1 chief at £500; 2 assistants at £200 each; 4 clerks at £80 each | 1,220 | 0 | 0 | |||
| 1 chief at £500; 1 assistant at £200; 4 clerks at £80 each | · · | |||||
| 2,608 | 8 | 0 | ||||
| Maintenance of Plant— | ||||||
| Motive power and dynamos: 10 per cent. on £18,010 | 1,801 | 0 | 0 | |||
| ””10 per cent. on £13,400 | · · | |||||
| Buildings and fittings: 5 per cent. on £11,000 | 550 | 0 | 0 | |||
| ”” 5 per cent. on £8,000 | · · | |||||
| Transformers: 10 per cent. on £7,500 | 750 | 0 | 0 | |||
| Accumulators: 15 per cent. on £9,600 | · · | |||||
| Mains: 7½ per cent. on £20,430 | 1,532 | 5 | 0 | |||
| ”2½ per cent. on £26,262 | · · | |||||
| Regulating gear: 10 per cent. on £500 | 50 | 0 | 0 | |||
| ”” 10 per cent. on £2,500 | · · | |||||
| 4,683 | 5 | 0 | ||||
| 11,939 | 13 | 0 | ||||
| 2,100 units × 365 days = 766,500 units. Cost per unit | · · | 3·75 d. | ||||
| Continuous Battery Transformer System. | ||||||
|---|---|---|---|---|---|---|
| Materials— | £ | s. | d. | £ | s. | d. |
| Coals: 4,380 tons at 17s. | · · | |||||
| ” 2,550 ”17s. | 2,167 | 0 | 0 | |||
| Oil, water, and petty stores: | ||||||
| 1,500 hours at 7 s. 6 d. | ||||||
| 7,250 hours at 1 s. | · · | |||||
| 1,400 hours at 5 s. | 350 | 0 | 0 | |||
| Total cost of material | 2,517 | 0 | 0 | |||
| Labour— | ||||||
| 2 foreman drivers at 45 s.; 6 drivers at 30 s.; | ||||||
| 9 firemen at 24 s.; sundry labour | ||||||
| 1 foreman driver at 45 s.; 2 drivers at 30 s.; | ||||||
| 3 firemen at 24 s.; sundry labour | 975 | 0 | 0 | |||
| Salaries— | ||||||
| 1 chief at £500; 2 assistants at £200 each; 4 clerks at £80 each | · · | |||||
| 1 chief at £500; 1 assistant at £200; 4 clerks at £80 each | 1,020 | 0 | 0 | |||
| 1,995 | 0 | 0 | ||||
| Maintenance of Plant— | ||||||
| Motive power and dynamos: 10 per cent. on £18,010 | · · | |||||
| ””10 per cent. on £13,400 | 1,340 | 0 | 0 | |||
| Buildings and fittings: 5 per cent. on £11,000 | · · | |||||
| ”” 5 per cent. on £8,000 | 400 | 0 | 0 | |||
| Transformers: 10 per cent. on £7,500 | · · | |||||
| Accumulators: 15 per cent. on £9,600 | 1,440 | 0 | 0 | |||
| Mains: 7½ per cent. on £20,430 | · · | |||||
| ”2½ per cent. on £26,262 | 656 | 10 | 0 | |||
| Regulating gear: 10 per cent. on £500 | · · | |||||
| ”” 10 per cent. on £2,500 | 250 | 0 | 0 | |||
| 4,086 | 10 | 0 | ||||
| 8,598 | 10 | 0 | ||||
| 2,100 units × 365 days = 766,500 units. Cost per unit | · · | 2·7 d. | ||||
With the exception of the amount allowed for depreciation of the accumulators, which time alone can show to be correct, the expenses may be said to be over rather than under-estimated; the 15 per cent. depreciation given in [Table IV]. is under what has hitherto been found necessary to allow for the renewal of the plates of a secondary battery.
If the mean of the two results in [Table IV]. are taken, the working cost per Board of Trade Unit will be 3·22d., which shows that with both systems, after making due allowance for interest on capital, directors’ fees, bad debts, and other sundries omitted by Mr. Crompton, there is a probability of a very fair return on the capital expenditure, and the prospect of a handsome dividend for an electric lighting company who can sell electricity at the average price of 7d. per Unit.