Electric Generation Units Research Articles

Simulation of Bull Run Supercritical Generation Unit

The Bull Run supercritical unit was simulated by a linearized mathematical model based entirely on physical laws and design data, using an approach verified by comparison of an earlier simulation with field tests. A large set of differential and algebraic equations was solved to obtain transient responses. These responses were matched by transfer functions to obtain a process model which represented all significant plant inputs and outputs. In this study, appropriate use was made of a small digital computer, a large digital computer, and an analog computer. The process model of the Bull Run unit is believed to be the most detailed mathematical model which has been obtained for a supercritical electrical generation unit.

Cost Curves for Electricity Generation

A problem of some interest and importance is the variation in cost per unit of electricity generation for different sizes of plant. Cross-sectional data, of the kind used here, relating to costs in different generating stations at the same time, when graphed, will give a rough approximation to the long-run cost curve, that is, the envelope of the short-run cost curves for individual stations. Strictly, of course, it cannot be assumed that undertakings are operating at the minima of their short-run curves. Particularly is this true when the commodity is in short supply and produced by local monopolies. The first point is the different meanings to be attached to the term cost . Prior to nationalisation, the Electricity Commission and, later, the Ministry of Fuel and Power, published information on works cost of generation which includes fuel, salaries and wages of generating station staff, maintenance and repairs. No separate information about such generation overheads as management expenses, interest charges, and depreciation provision or sinking fund payments was provided. Examination of data, however, in a small sample of complete local authority accounts suggests that these other items behave in a manner not significantly dissimilar from works cost, so perhaps the inevitable concentration on the latter is not without justification on grounds other than availability of the statistics. Next is the fact that there are several different systems of generation. In I947, the last year for which the Ministry of Fuel and Power reported, in 202 of 334 stations operating the prime-mover was a steam engine, in eighty-two an oil engine, and forty were driven by water-power. On the criterion of size the predominance of steam generation was even more marked. The steam stations accounted for 96.9 per cent. of the total units generated, while 2.8I per cent were generated by water-power. It is thus reasonable, in examining costs, to concentrate on the dominant type-

水力発電所

A hydraulic power plant for generation of electricity includes a hydraulic speed breaker, that includes a speed breaker, a set of springs attached to ends of the speed breaker, wherein the springs are compressed when a vehicle rolls over the speed breaker, and is released when the vehicle moves away. A cylindrical portion includes a piston parallel to the speed breaker and attached thereto, wherein the piston is configured to move downwards when a vehicle rolls over the speed breaker, to cause an increased pressure in the portion below piston and suction in a portion above the piston, and wherein the piston move upwards on release of the set of springs to cause an increased pressure in a portion above piston and suction in a portion below piston. A reservoir is disposed at a ground level and a storage tank is disposed at a predetermined height from the ground level, and connected to the cylindrical portion. The fluid is pumped upwards from the reservoir to the storage tank by way of the cylindrical portion during downward and upward motion of the piston. An electricity generation unit (EGU) is connected to the storage tank and the reservoir, for converting the potential energy of the fluid stored in the storage tank to electricity.

Discussion: “First Large Gas-Engine Installation in American Steel Works: Description and Operating Characteristics of Sixteen Blowing-Engine Units of 2000 H.P. Each, Eight Electric-Generating Units of 1000 H.P. Each and Gas-Cleaning Plants” (Coleman, E. P., 1910, Trans. ASME, 32, pp. 1361–1450)

Discussion: “First Large Gas-Engine Installation in American Steel Works: Description and Operating Characteristics of Sixteen Blowing-Engine Units of 2000 H.P. Each, Eight Electric-Generating Units of 1000 H.P. Each and Gas-Cleaning Plants” (Coleman, E. P., 1910, Trans. ASME, 32, pp. 1361–1450)

First Large Gas-Engine Installation in American Steel Works: Description and Operating Characteristics of Sixteen Blowing-Engine Units of 2000 H.P. Each, Eight Electric-Generating Units of 1000 H.P. Each and Gas-Cleaning Plants

First Large Gas-Engine Installation in American Steel Works: Description and Operating Characteristics of Sixteen Blowing-Engine Units of 2000 H.P. Each, Eight Electric-Generating Units of 1000 H.P. Each and Gas-Cleaning Plants