Capacity Of Renewable Energy Sources Research Articles

Integration of Electricity from Renewable Energy Sources — The Czech Story

Integration of electricity from renewable energy sources is currently a big issue that affects all areas of the power industry (generation – transmission – distribution –consumption) and it relates to all highly developed as well as developing power industry systems. There has recently been a significant increase of installed capacity of renewable energy sources, especially of photovoltaic power plants in the Czech Republic. High levels of electricity generation from renewable energy sources occur during favorable weather conditions in the Central Europe region. This causes loop flows and overloading of transmission systems in the whole region. Huge development of renewable energy sources in the region considerably affects both the distribution system and the transmission system of the Czech Republic. Operation of the Czech power system is negatively influenced and project development of the power system needs to be repeatedly modified and updated. Steeply raising development of subsidized renewable energy sources in Europe and in the Czech Republic brings about many challenges and risks, technical as well as economic and social.

Utilization of renewable energy sources in hard mineral mining

In focus is the current objective of energy efficiency improvement in mining in Russia and in other countries of the world. The world tendencies toward new unconventional renewable energy sources and their introduction in closed-cycle resource-saving technologies are reviewed. In the capacity of renewable energy sources, the authors discuss lithological pressure and elastic vibration of rock mass, kinetic energy of gravity flow of backfill mixtures and fluids during backfilling and mine drainage, potential energy of gravity force of heavy trucks, energy of return air flows in mine ventilation and this energy recovery, etc. The authors think that conversion of these kinds of energy into electric energy during hard mineral mining will allow a solution to ecological problems and enable development of allied branches in “small power engineering,” including essential reduction of external energy consumption in underground mines.

A new method for day-ahead sizing of control reserve in Germany under a 100% renewable energy sources scenario

In Germany, the installed capacity of renewable energy sources, especially that of wind and photovoltaic energy, has increased over the past few years and will continue to increase in the future. Due to errors in forecasting wind and photovoltaic energy, the control reserve needed to balance the electricity system will correspondingly increase if control reserves will be sized statically for several months or one year as it is done in most countries today [1–3]. That is because sizing control reserves this way does not consider the fact that there will be hours with a high penetration of wind and photovoltaic which cause a different demand for control reserves than hours with a lower penetration. Therefore, in this work, we present a new probabilistic dynamic method that sizes control reserves for the single hours of the following day making use of forecasts of the power feed-in of wind and photovoltaic. In contrast to similar approaches [2,3] forecast errors of wind and photovoltaic power are not modeled as normal distributions, which does not reflect reality [4–6], but by kernel density estimation to get more realistic distributions. Under a 100% renewable energy scenario for Germany, the control reserve that would be allocated by the dynamic method is compared with the control reserve that would be allocated by a static method. The static method is similar to the probabilistic Graf-Haubrich method, which is applied in Germany today, but can, in contrast to this method, be applied to future scenarios. It is shown that the dynamic method halves the average required control reserve.

Transmission Network Expansion Planning for the Penetration of Renewable Energy Sources - Determining an Optimal Installed Capacity of Renewable Energy Sources

Due to global environmental regulations and policies with rapid advancement of renewable energy technologies, the development type of renewable energy sources (RES) in power systems is expanding from small-scale distributed generation to large-scale grid-connected systems. In the near future, it is expected that RES achieves grid parity which means the equilibrium point where the power cost of RES is equal to the power costs of conventional generators. However, although RES would achieve the grid parity, the cost related with development of large-scale RES is still a big burden. Furthermore, it is hard to determine a suitable capacity of RES because of their output characteristics affected by locations and weather effects. Therefore, to determine an optimal capacity for RES becomes an important decision-making problem. This study proposes a method for determining an optimal installed capacity of RES from the business viewpoint of an independent power plant (IPP). In order to verify the proposed method, we have performed case studies on real power system in Incheon and Shiheung areas, South Korea.

Renewable energies impacting the optimal generation mix: The case of the Iberian Electricity Market

In the last few decades, electricity markets have undergone extensive reforms. A process of liberalizing electricity markets has been implemented by several countries, reducing the incumbents' market power. Thus, generation and retail are open to competition, while transmission and distribution remain regulated. Furthermore, the need to comply with the targets set by the Kyoto Protocol has boosted the installed capacity of renewable energy sources, such as wind power. Therefore, it is important to study what the impact of a renewable source like wind power will be on the optimal generation capacity mix, assuming producers can invest in other technologies and the wholesale market is open to competition. In this article, we assume two alternative generation technologies – wind and combined cycle gas turbines – as a simplifying assumption. We develop a two-stage model for the Iberian Electricity Market, where the choice of the capacity construction occurs in the first-stage, before electricity demand is known, and the optimal outputs and daily equilibrium prices are obtained in the second-stage, under the assumption that electricity demand does not exceed installed capacity. The application of this model reveals that producers can be expected to increase their renewable generation capacity (wind power).

Study of Renewable Energy Sources Capacity and Loading Using Data Logger for Sizing of Solar-wind Hybrid Power System

Abstract If the sizing of renewable energy power plant is planned with a less reliable data of its energy sources, usually in the future, the power system will have poor performance. Such cases often occur in various regions, including Indonesia. This problem can be solved through observation and measurement in the power systems using a data logger. Data logger is the electronic equipment which can record the formation of data accurately. In this paper, the current and voltage formation of solar-wind hybrid power system which is recorded by the data logger will be analyzed. The results then will be used for resizing strategy of the plant, especially which was established but still showed indications of inefficiency. Furthermore, by using the Levelized Cost of Electricity (LCOE), the system energy cost before and after resizing will be compared. The data logger is also used to see the capacity of the energy source by applying the indirect method.

Effect of demand response on the marginal electricity used by plug-in electric vehicles

Plug-in electric vehicles (PEV) are considered to be a potentially sustainable alternative to conventional vehicles for private transport and a way of balancing intermittent generation from renewable energy sources (RES). Using RES for electric mobility would be superior to all available fossil generation alternatives in terms of emissions and efficient energy conversion. To quantify the marginal energy from RES used, two charging strategies last trip charging and optimized demand-side management (DSM) with dynamic pricing are investigated for a German long-term high RES power mix scenario. The results for both charging cases indicate that the power demand for PEVs will not be met by RES. For last trip charging 1.40% comes from RES. In terms of DSM this share increases to 7.38% but results in higher overall CO2 emissions because for Germany coal provides the lowest cost fossil power. Hence DSM charging reduces peak load and helps to balance RES generation but is contrary to the original idea of clean transportation because of higher marginal emissions caused by the utilisation of coal. To account for contractual arrangements allowing consumers to directly purchase RES electricity, a second scenario with additional installed RES capacity is analysed. Because of the high RES share of over 50 % a complete usage of the RES is not possible and a small fraction of power must still be provided by dispatchable power plants. For the second scenario, DSM charging also allows for an increased use of RES compared to last trip charging (99 % versus 90% RES). In addition, total marginal CO2 emissions are lower and DSM helps to balance the ramping of RES. Therefore, it is concluded that for Germany the installation of additional RES and DSM charging would guarantee clean transportation using electric vehicles.

How to deal with negative power price spikes?—Flexible voluntary curtailment agreements for large-scale integration of wind

For the large-scale integration of electricity from renewable energy sources (RES-E), the German system seems to reach its limits. In 2009, the electricity wholesale market experienced serious negative prices at times of high wind and low demand. The feed-in system in Germany consists of a fixed feed-in price, a take-off obligation and a RES priority rule, and in practice only very restrictive use of RES-E curtailment. Exactly the latter is the problem. We argue that the overall performance of the system would improve seriously by lifting the restrictions on the use of voluntary curtailment agreements, while retaining the priority rule as such. Since generators of RES-E can only improve under this system reform, investment conditions improve, leading to higher installed RES-E capacity. This in turn implies that reduced wind output due to curtailment can actually be offset by higher wind output in all periods in which there is no problem.