Design and Operational Aspects of Gas and Steam Turbines for the Novel Solar Hybrid Combined Cycle SHCC®

Abstract

Solar hybrid power plants are characterized by a combination of heat input both of high temperature solar heat and heat from combustion of gaseous or liquid fuel which enables to supply the electricity market according to its requirements and to utilize the limited and high grade natural resources economically. The SHCC® power plant concept integrates the high temperature solar heat into the gas turbine process and in addition — depending on the scheme of the process cycle — downstream into the steam cycle. The feed-in of solar heat into the gas turbine is carried out between compressor outlet and combustor inlet either by direct solar thermal heating of the pressurized air inside the receivers of the solar tower or by indirectly heating via interconnection of a heat transfer fluid. Thus, high shares of solar heat input referring to the total heat input of more than 60% in design point can be achieved. Besides low consumption of fossil fuels and high efficiency, the SHCC® concept is aimed for a permanent availability of the power plant capacity due to the possible substitution of solar heat by combustion heat during periods without sufficient solar irradiation. In consequence, no additional standby capacity is necessary. SHCC® can be conducted with today’s power plant and solar technology. One of the possible variants has already been demonstrated in the test field PSA in Spain using a small capacity gas turbine with location in the head of the solar tower for direct heating of the combustion air. However, the authors present and analyze also alternative concepts for power plants of higher capacity. Of course, the gas turbine needs a design which enables the external heating of the combustion air. Today only a few types of gas turbines are available for SHCC® demonstration. But these gas turbines were not designed for solar hybrid application at all. Thus, the autors present finally some reflections on gas turbine parameters and their consequences for SHCC® as basis for evaluation of potentials of SHCC®.

Design and Performance Analysis of a Novel Integrated Solar Combined Cycle (ISCC) with a Supercritical CO2 Bottom Cycle

“…Among the numerous solutions, the integrated solar combined cycle (ISCC) system is one of the most effective solutions, which is based on the gas turbine combined cycle (GTCC) benchmark system coupled with solar energy. This system not only ensures a stable power supply but also is more efficient than the more costly solar electric generating system (SEGS) [1]. The concept was first developed through Luz International Corporation [2].…”

Thermal Study of a Parabolic Trough Collector

“…It plays an important role in fossil fuel saving and CO2 emission mitigation. Electricity production requires high temperatures of 400 ° C to 1200 ° C. These temperatures can be provided by concentration of the solar radiation with the aid of various types of collector systems which can achieve temperatures of 1000 °C (Heide, 2010). Solar Concentration Systems have been widely developed and they are considered to be an effective tool for conversion of solar energy.…”

Ανάλυση Διατάξεων Παραγωγής Ισχύος Από Θερμικές Στροβιλομηχανές Με Χρήση Ηλιακής Ενέργειας

“…Αυτό συνεπάγεται την εγκατάσταση της μηχανής στην κορυφή του πύργου, οπότε ο τελευταίος απαιτείται να αποτελεί στιβαρή και δαπανηρή κατασκευή αφού πρέπει να φέρει και το βάρος της μηχανής, της γεννήτριας κτλ. Οι Heide et al (2010) παρουσιάζουν άλλες λειτουργικές διατάξεις οι οποίες αντιμετωπίζουν αυτό το πρόβλημα. Συγκεκριμένα, η μηχανή μπορεί να βρίσκεται στη βάση του πύργου και το θερμό μέσο να μεταφέρεται δια μέσου σωλήνωσης (Σχήμα 1.12 (b)).…”

“…Σχήμα 1.12. Διατάξεις πύργου (Heide et al, 2010;Kribus et al, 1998) Οι εγκαταστάσεις που κάνουν χρήση αυτής της τεχνολογίας είναι λιγότερες από αυτές των κοίλων κατόπτρων και αφορούν μόνο κύκλους ατμοστροβίλου (NREL, 2016) ισχύος 10-150MW απαιτώντας επιφάνεια 8-12 m 2 MWh -1 y -1 (Müller- Steinhagen & Trieb, 2004). Η δυνατότητα επίτευξης υψηλής θερμοκρασίας (>1000 ο C) καθιστά δυνατή την εφαρμογή αυτής της τεχνολογίας σε κύκλους αεριοστροβίλου, που βρίσκεται όμως σε πειραματικό στάδιο (EU Commission, 2005;Heller, 2011;Quero et al, 2014).…”