Vízügyi Közlemények, 1989 (71. évfolyam)

2. füzet - Szeredi István: A szivattyús energiatározás és villamosenergia rendszerünk

A szivattyús energiatározás és villamosenergia-rendszerünk 259 supported by a pumped energy storage system. At the same time, the hydrocarbon consumption of an electric energy system can be leveled and later gradually decreased by pumped energy storage, while the use of gas-turbines gradually increases the consumption of hydrocarbons. Changes in fuel costs are summarized in Fig. 3. It can be stated that the cost of a pumped energy storage system is lower in every investigated time period and in any investigated case than that of the gas-turbines. Fuel-cost differences between the two development schemes, and the savings due to the work of energy storage systems can be characterized. These are presented in Fig. 4. as a function of time. Changes in specific fuel costs are shown in Fig. 5. Annual savings in fuel amounted to 30-60 PJ - according to Fig. 6. - after the pumped energy storage system has been set into operation. Beyond 2002 the savings soared to 150-160 PJ annually. Gas-turbine development is basically a gradually increasing gas-turbine capacity. According to Fig. 7, the costs of investigated gas-turbine plants were consistently higher than the investment costs of domestic energy storage systems. There is a straight interconnection between the fluctuation of fuel-costs and the usable capacity of pumped energy storage systems. This relationship is appearent from Fig. 8 where overall fuel costs in characteristic years are plotted against the usable capacities of pumped energy storage systems. The capacities of control power stations needed for a smooth performance of our electric energy system are shown in Fig. 9 as functions of the capacity of pumped energy storage systems. Total investment costs are presented in Fig. 10. Minimum investment cost for the needed peakenergy production is coincident with a capacity of 1200 MW for our planned energy storage system. Return periods presented in Fig. 11 characterize well the ratio of investment costs of the energy storage system and fuel-cost savings of the overall electric energy system. Based on this, a capacity of 1200 MW would be most favourable in 1997 and 2002 (the years of realization). The built-in capacity of an energy storage system is determined by the demand set against the pumps: about 70-75 percent of the built-in capacity is needed to operate the turbines ( Fig. 12). The rest can be used as a breakdown reserve. Compared with the investment costs of 1997 (the first time-point of setting into operation) the damages can be calculated of each alternative time-point according to our selection. The rate of increases is demonstrated in Fig. 13. Minimum costs - on a national level - can be obtained by a simultaneous start of operation of an atomic power plant with a capacity of 2 x 1000 MW. Actual processes of recovery of the costs invested are presented in Fig. 14 for different credit-structures and on a base price level of 1985. Recovery intervals are shown in Table I. The construction of a pumped energy storage system will substantially equalize the work of our national energy system. The structure of used fuel-materials can be rationalized. Its fast control-capability will ease a proper scheduling in the overall electric system and prevent unwarranted breakdown. * * * Pumpspeicherwerke und das ungarische Stromenergiesystem von Dr.-lng. István SZEREDI, CSc Im Interesse einer Gewährleistung der notwendigen Elastizität des ungarischen Stromenergiesystems wurden die Möglichkeiten der Entwicklung über Pumpspeicherwerke und über Gasturbinen bei einem 2,5 bzw. 3 prozentigen Zuwachs des Energieanspruchs untersucht. Dazu wurde ein numerisches Systemmodell verwendet, welches die das Funktionieren des Stromenergiesystems kennzeichnenden Tages- und Wochenzyklen in 1-Stunden-Zeitschritten abbildet. Für die Funktion des numerischen Systemmodells wird in Bild 1. ein Beispiel gezeigt. Es ist daraus u. a. ersichtlich, in welchem Maße die Pumpspeicherung die Tagesbelastungen ausgleicht und zu welchem Spitzenbetrieb die Kohlenwasserstoff-Kraftwerke, im Fall einer GasturbinenEntwicklung, gezwingen sein würden.