28 Electricity as an Illuminant. 



tricity or gas, I say that electricity can be produced as cheaply 

 from coal as gas can be in the same place. 



Mr. Andrews — That is certainly a very good statement in 

 favour of electricity, and we sincerely hope it will be carried 

 out. In Galway their electricity is entirely produced by water- 

 power. 



Mr. Perry — But we had to buy our power. 



Mr. Andrews — Might I ask at what ratio would that water 

 power cost you per indicated horse-power .? 



Mr. Perry — You cannot talk ot the I.H.P. of turbines. The 



indicated horse-power of a steam-engine is the rate of work 



actually done by the steam in the cylinder ; — it is given by 



the area of the indicator diagram : the actual horse-power 



would be found by a brake on the main sbaft : it is always less 



than the I.H.P. In the case of turbines the gross horse-power, 



. lbs. of water per min. X feet of fall . , , , , 



VIZ., is probably the analogue 



33,000 



of I.H.P. At Galway this is more than 200 H.P., and we 

 are able to deliver 100 H.P. as electricity at consumers' lamps 

 throughout the 24 hours. By making use of storage, running 

 24 hours, and discounting for loss, we can deliver during 6 hours 

 of lighting 300 H.P. at lamps : i.e.^ our water power capacity is 

 about 6,000 eight candle lamps for six hours a day. The 

 capital cost of this is about ;^3,ooo, which at 5 per cent, is ^150 

 a year, and works out to be less than xV^h penny a unit. How- 

 ever, this calculation does not close the question ; the first cost 

 of storage batteries has to be added and their upkeep, and a 

 comparison made with the amount of storage advisable in the 

 case of generation from coals. I cannot give the information 

 you want right off, because it involves a little calculation. We 

 have the water power attached to the mills in Galway. We 

 have no rent to pay at all ; we bought our mills and own them 

 in fee, and there is interest on the cost of the construction. We 

 have to pay for the general maintenance. As I have said we 

 have spent ;^7,ooo. ^100 a year runs it, and we are earning a 

 fair dividend at the present time, though only a few places are 

 on. 



