1,A hydroelectric plant utilizing a continuous flow of 15CFS with an absolute head of 900ft was built 4 ago. The 20" diameter existing pipeline cost $200,000 for pipe, installation and right of way has a friction head loss of 85ft. Additional water rights have been acquired which will result in a total flow of 30CFS. The following plans are under consideration for using the total available water flow. Plan I use the present pipeline. This will entail no additional expense but will increase the friction head by a factor of 4 to 340 ft. Plan II, add an additional 20" pipeline at a cost of $100,000. The loss of head for this pipeline will now be 85ft, as each pipeline carries 15CFS as before. Plan III is to build a 26" diameter pipeline at a cost of $200,000 and remove the existing line for which a $10,000 can be realized as scrap. The energy of the water delivered to the turbine of the power plant is valued at $135 per horsepower year. Horsepower is given by HP= h x F x 62.4/550, where h is head in feet (900-friction loss) and F is the flow in CFS. Insurance and taxes are 5% of first cost for all three plans. Operating and maintenance costs are the same for all three plans. Marr is 12%. If all lines are retired in 25 years without any salvage value, what are the comparable annual costs for the three plans? 1,A hydroelectric plant utilizing a continuous flow of 15CFS with an absolute head of 900ft was built 4 ago. The 20" diameter existing pipeline cost $200,000 for pipe, installation and right of way has a friction head loss of 85ft. Additional water rights have been acquired which will result in a total flow of 30CFS. The following plans are under consideration for using the total available water flow. Plan I use the present pipeline. This will entail no additional expense but will increase the friction head by a factor of 4 to 340 ft. Plan II, add an additional 20" pipeline at a cost of $100,000. The loss of head for this pipeline will now be 85ft, as each pipeline carries 15CFS as before. Plan III is to build a 26" diameter pipeline at a cost of $200,000 and remove the existing line for which a $10,000 can be realized as scrap. The energy of the water delivered to the turbine of the power plant is valued at $135 per horsepower year. Horsepower is given by HP= h x F x 62.4/550, where h is head in feet (900-friction loss) and F is the flow in CFS. Insurance and taxes are 5% of first cost for all three plans. Operating and maintenance costs are the same for all three plans. Marr is 12%. If all lines are retired in 25 years without any salvage value, what are the comparable annual costs for the three plans
