Poļina Ivanova

Combined heat and power plants towards efficient and flexible operation

The integration of large-scale renewable energy sources into the power system and the implementation of market mechanisms have changed the operation of combined heat and power (CHP) plants. Technical and organizational measures should be taken to operate power plants efficiently and flexibly in line with new running conditions. There are different kinds of possibilities to ensure flexible operation of CHP plants. In line with the review and analysis of the provided literature all measures were generalized and divided in five groups. At the end, an example of the research topic is presented in the context of Riga CHP-2 plant.

Electricity Market Liberalisation and Flexibility of Conventional Generation to Balance Intermittent Renewable Energy – Is It Possible to Stay Competitive?

Abstract Intermittent generation (solar PV and wind energy) integration in power production portfolio as well as electricity price fluctuations have changed the running manner of conventional combined heat and power (CHP) plants: the shift from base load operation to running in cyclic modes. These cogeneration power plants are not adapted to new running conditions. The level of CHP plant flexibility should be improved to operate profitably and efficiently from both technical and fuel usage point of view. There are different ways to increase the flexibility of power plants. Before any improvements, the situation at power plants should be evaluated and the weakest points defined. In this publication, such measures are presented on Riga CHP-2 plant example: installation of heat storage tank; extension of operation rang; acceleration of start-ups.

Development of a System Dynamics Model for Evaluation of the Impact of Integration of Renewable Energy Sources on the Operational Efficiency of Energy Supply Facilities: Theoretical Background

Abstract Nowadays, energy companies operate in a highly competitive environment. To maintain the leader position, as a reaction to various changes energy companies must take appropriate steps in a timely manner. Correct assessment of the situation ensures implementation of adequate measures. The situation can be assessed correctly by using a complex approach and/or analysing it according to the specific circumstances. The complex approach also envisages designing of an appropriate model, which studies the impact of changes on the research object, while dealing with the object within a system and as part of the system. The article gives a theoretical background of the system dynamics model in order to evaluate the impact of integration of renewable energy sources (RES) on the operational efficiency of energy supply facilities (power and heat supply) on the national and regional levels, as well as provides the first modelling results.

Cost — benefit analysis of CHP plants taking into account air cooling technologies

The ambient temperature has a negative effect on gas turbine (GT) performance, i.e., the power output of GT decreases with the increment of ambient air temperature. This negative effect is solved by means of air cooling at the input of compressor of GT unit. Mainly the air cooling technologies are widely used in the regions with hot climate to produce surplus of electricity and cover the peak demand of it. In this publication the methodology is developed for the evaluation of the economic benefit from air cooling technologies by selling surplus of electricity at electricity power exchange, i.e., the adjustment of combined and heat power (CHP) plants operation to the electricity price fluctuations through the use of air cooling technologies.