Abstracts - VGB PowerTech Journal 9/2012

Hydropower - Backbone of green energy sales

David Klee, Ralf Bischof and Michael Detering

The expansion of renewable energy sources has boosted in recent years and will be promoted in the future. Hydropower shows high capacity factors, is simple to store and highly predictable. Due to its versatility, hydropower is the backbone of most green energy products. Larger portfolios of hydropower plants even allow for structured long-term contracts, normally backed by thermal capacities.

Hydropower development in South East Europe - Experience report

Gerald Berger and Hans-Christoph Funke

South East Europe offers high undeveloped potential of hydropower compared to West Europe. That is the main reason why Austrian’s Kelag and Germany’s RWE Innogy started project development in this region. An overview about the projects under development, construction and in operation is given. Finally the characteristics and track record of individual projects is described.

Modular pump-turbine concept supporting the integration of renewable energy sources in a decentralised grid

Eduard Doujak, Philipp Unterberger and Christian Bauer

The integration of renewable energy systems in Europe leads to several challenges in the energy market. Energy storage for stable grid operation has become a necessity. Pumped storage is the only technology available today that is able to store large amounts of energy efficiently and with low specific storage costs. The Vienna University of Technology is currently investigating how existing artificial lakes for snow production could be integrated in pumped storage production systems. A new modular pump turbine concept and its application prospects are presented.

Future trends in the wind energy industry - Conventional power plant engineering provide blueprint for forward-looking process and quality planning

Ronald Horstjan

Wind energy is still a young industry in need of forward-looking process and quality planning to manage energy-related costs arising from the necessary energy turnaround. Concrete strategies are described. One example are pitch systems for the wind industry. The relevance of interdisciplinary collaboration between turbine manufacturers and supply industries is also highlighted. The main objective is to establish standards resulting in more efficient process- and quality planning to increase the availability and speed to market pitch systems for different turbine types.

Status and future development of solar thermal power plants

Reiner Buck and Klaus Hennecke

Solar thermal power plants are an often under-valued component of a future sustainable energy system. Integrated heat storage or supplementary firing add the ability to provide power on demand. Despite early market success, further effort is required to increase efficiency and lower cost, to achieve competitiveness in the market. This paper describes the different technologies and provides examples to demonstrate the present state of the art. The main research concepts for technological progress will be described and an outlook on the role of CSP in a future energy system will be given.

Energy storage for renewable energies

Martin Kleimaier

The current energy concept of the German Government is based on a steadily increasing penetration of renewable energies. Up to the year 2050 the penetration rate in the power sector should have reached 80 %. This translates to the need for an installed power of PV and wind of approximately 150,000 MW in addition to conventional thermal power stations, whereas the load is expected to be in the range of 80,000 MW. Different storage technologies and strategies arise depending on the application. Especially the balancing of longer periods needs huge storage capacity, thus requiring a cheap storage medium and/or high energy density.

Highly efficient controllable µCHP system as part in a virtual power plant

Karl Föger and Frank Dahlmanns

The use of micro-CHP units as an effective option for grid control is presented. A controllable micro-CHP unit with a net electrical efficiency of 60 %, power modulation rates of 6.25 % absolute/minute and all-year availability is presented - an ideal component of a virtual power plant. The “engine” of this highly efficient and flexible micro-CHP system is a fuel cell module based on solid oxide fuel cell technology.

STEAG and renewable energies

Wolfgang A. Benesch and Stephan Nahrath

Steag’s activities in power generation last now for 75 years. These are based on fossil fuels but also - now for more than ten years - on renewables. STEAG believes in the energy mix which means coexistence of conventional and renewable energies. This is to ensure highly available, economical energy supply. Especially the latter is for an industrial country like Germany of high importance. Besides, the use of renewables itself like biomass, biogas deep geothermal energy, solar thermal and wind energy, the improvement of dynamics and the reduction of minimum load of conventional plants is of high importance.

Power system operation for system operators and power production operators - Common simulator-based training

Udo Spanel

It is the obligation of Transmission System Operators to ensure at any moment secure and reliable supply of electricity. In today’s environment, this task requests cooperation of multiple system operators and power production operators in the control centres caused by the liberalisation of the supply industry. The implementation of the ambitious objectives for climate protection put new challenges to operate the entire power system according to secure and reliable supply. Common operator trainings increase the strength of cooperation to fulfil complex tasks, especially occurring in emergency and restoration situations.

Development of a resilient mechanical sealing solution to resist electro corrosion in ultra-pure feedwater applications

Gerard van Loenhout, Klaus Enders and Rainer Schmerberg

Ever since the introduction of mechanical seals on high speed boiler feed pumps in the sixties, mechanical seals have proven to be a reliable, cost effective sealing method. However, since the introduction of combined water treatment chemistry used in today’s modern fossil-fuelled power stations, keeping mechanical seal reliability high, became a challenge. A pragmatic approach is presented. A resilient sealing solution was developed to resist electro corrosion for such critical feed water pumps.

Optical dissolved oxygen measurement in power plants - A comparison of amperometric and optical dissolved oxygen sensors for applications at low oxygen levels

Stephan Bell, Frank Dunand, Martin Schubert and Ralf König

The majority of existing dissolved oxygen analysers use amperometric sensors. Whilst these are renowned for their accuracy and reliability, issues encountered by users include maintenance complexity and frequency in addition to flow dependence and calibration needs. Luminescence technology has been used in power plants since 2006. In 2009, the first luminescent oxygen sensor with a sub-µg kg-1 accuracy for use in power plants was launched. Both techniques are compared to the use in fossil and nuclear power plant applications.

Treatment of waste water from flue gas cleaning

Klaus Ogiermann, Klaus Hagen, Thomas Meyerhoff, Juan Luis Basabe and Michael Vendrup

Strict limits must be adhered to for treating waste water incurred during flue gas desulphurisation (FGD). One and two-stage precipitation processes have proven themselves in FGD waste water treatment. Metals can be removed with the MetClean® process. Another option is evaporation. Waste water ZLD systems (Zero Liquid Discharge) recover, via a falling film evaporator with subsequent crystallisation, more than 98 % of the water and produce, aside from the condensate, only solid material that can be disposed of in landfill. A further development, named ZLD CoLD™, significantly reduces the investment and operating costs of this solution.

Perspectives of the German lignite industry in 2012: Stability through diversity

Johannes F. Lambertz and George Milojcic

The annual status report at the Lignite Conference was presented under the heading “Stability through diversity”. Germany will be phasing out nuclear energy by 2022 and giving a big push to renewables as substitute. This makes lignite more valuable as domestic energy. Lignite-fired power plants are always available but must be operated ever more flexibly. In the time horizon 2030, lignite‘s importance must be assessed in a global and European context. Lignite can go on playing an important role in a diversified electricity mix, with CO2 emissions being limited by Europe‘s cap-and-trade system (ETS).

Brief report on the activities of VGB PowerTech in 2011/2012

VGB PowerTech e.V. is the European technical association for heat and power generation. The work of VGB largely depends on the many supporters and employees in the companies and the VGB office which manages the activities of the committees of VGB´s Competence Centres “Nuclear Power Plants”, “Power Plant Technologies”, “Renewables and Distributed Generation”, “Environmental Technology, Chemistry, Safety and Health” and “Technical Services”. VGB is also involved in power plant research through its research foundation and promotes important topics with funds from its member companies. In addition to this work, VGB organises seminars, symposia, conferences and the annual Congress “Power Plants”. These conferences are further platforms for the international exchange of experience - just like the journal at hand.