Maximum Rainfall Model Based on Archival Pluviographic Records – Case Study for Legnica (Poland)

The scope of this study is to develop a probabilistic model for maximum rainfall in Legnica, based on a 50-year series of pluviographic records. The present authors uses Fréchet, Gamma, Generalized Exponential Distribution (GED), Gumbel, Log-Normal and Weibull distributions to describe the measurement data. Distributions parameters are estimate using maximum likelihood method. Coincidence of the analyzed theoretical distributions with measured data are inspected using the Anderson-Darling test, while the best fitting distribution is chosen by Bayesian information criterion (BIC) of Schwartz as well as by the relative residual mean square error. Among others distributions Fréchet, Gamma, GED, and Weibull distributions fulfill the compliance criterion for each of the 20 analyzed rainfall durations. BIC criterion indicates for a GED, but differences between GED, Gamma and Weibull is minor. Only RRMSE analysis revealed that in comparison to other distribution GED best describes the measurement rainfall data. At first glance maximum rainfall model was well described by the generalized exponential distribution. However, there is a substantial inconvenience to use it for engineering purposes. Generalization of the shape parameter α depended on the rainfall duration, by averaging and then recalculating remaining parameters λ and γ brought relatively simpler form of model.

The impact of long-term changes in air temperature on renewable energy in poland

This paper analysed from the statistical point of view the trends in observed air temperature in major Polish cities and presented a qualitative analysis of their potential impact on the operation of the selected renewable energy sources. It also reviews the relation between the air temperature and observed electrical load as well as changing numbers of cooling and heating degree days. The method involved a statistical analysis of historical mean daily temperature observed in 19 major Polish cities over the 1968–2018 period. The air temperature change impact on renewable energy sector in Poland, by affecting the heating and cooling demand, the electrical load and the renewables working conditions both, on supply and demand side. The analysis reports that the mean daily temperature in all major polish cities is exhibiting a statistically significant increasing trend, up to 0.52 °C/decade. The observed increase in air temperature reduces the heating demand in Poland, beneficially for the environment and renewable supply. Increasing cooling needs in summer raises the energy consumption and indoor thermal stress. The climate warming affects the operation conditions, energy source, driving force, capacity and efficiency of renewable energy sources. The investigated changes were favourable and unfavourable depending on the renewable technology and operation mode, and were stronger on the demand side than on the supply side

Long-term trends in 20-day cumulative precipitation for residential rainwater harvesting in Poland

Abstract: Rainwater harvesting (RWH) for domestic uses is widely regarded as an economic and ecological solution in water conservation and storm management programs. This paper aims at evaluating long-term trends in 20-day cumulative rainfall periods per year in Poland, for assessing its impact on the design and operation conditions for RWH systems and resource availability. The time-series employed corresponds to a set of 50-year long time-series of rainfall (from 1970 to 2019) recorded at 19 synoptic meteorological stations scattered across Poland, one of the European countries with the lowest water availability index. The methods employed for assessing trends were the Mann–Kendall test (M–K) and the Sen’s slope estimator. Most of the datasets exhibit stationary behaviour during the 50-year long period, however, statistically significant downward trends were detected for precipitations in Wrocław and Opole. The findings of this study are valuable assets for integrated water management and sustainable planning in Poland

Forecasting the Nysa Kłodzka flow rate in order to predict the available flow for a run-off-river (ROR) power plant

Hydroelectricity is generally perceived as a stable and predictable power source. However ROR power plant without reservoir energy output is mainly driven by changing flow rate. This study applies artificial neural networks to create flow rate forecasts with one hour lead time. Forecasting models were built for Nysa Kłodzka catchment which possesses significant potential for new hydropower plants development as well as leads to frequent floods. The best of the obtained model gives satisfactory results both in terms of root mean square error (0.6379 m3/s) as well as Nash-Sutcliffe performance indicator (0.9978). Obtained results were compared with currently used forecasting models and were proven to be superior

An ordinary life of information about a dangerous hydrological phenomenon

Celem niniejszej pracy było przedstawienie cyklu życia informacji o niebezpiecznym zjawisku hydrologicznym w kontekście komunikacji społecznej. W pracy zaprezentowano opis funkcjonowania i struktury systemu przygotowania analiz zawiązanych z oceną obecnego i przewidywanego stanu atmosfery i hydrosfery. Poruszono również proces przekazywania powstałej informacji o zagrożeniach pomiędzy instytucjami państwowymi w społeczeństwie. Praca dotyka również form komunikacji IMGW-PIB poprzez telekomunikację oraz kolory, które funkcjonują w przestrzeni społecznej od dziesiątek lat i podlegają rozwojowi wraz z postępem technologicznym współczesnego świata.The aim of this paper was to describe a life cycle of information about a dangerous hydrological phenomenon in the context of social communication. The paper presents a description of the functioning and structure of the atmosphere and hydrosphere current and predicted state system regarding to necessary analyzes and related assessments. The process of hydrological and meteorological information transition between state institutions in the society was also discussed. The work also affects IMWM-NRI communication forms through telecommunications and colors that have functioned in the social space for decades and are subject to development along with the technological progress of the modern world

Assessing temporal complementarity of solar, wind and hydrokinetic energy

Renewable energy sources (RES) exhibit various characteristics when it comes to their availability in time and space domain. Some are characterised by significant variability and limited predictability. This makes their integration to the power grid a complicated task. Temporal and spatial complementarity of RES is perceived as one of the possible ways to facilitate the process of integration. This paper investigates the concept of temporal complementarity of solar wind and hydrokinetic energy in case of two sites in Poland. Obtained results indicate existence of some beneficial complementarity on inter-annual and annual time scale. Combination of those three RES in one hybrid system makes power source more reliable

RAINWATER RETENTION ON THE HEAVILY INDUSTRIALIZED AREAS

The paper presents the dimensioning of retention reservoirs indicator method regarding to the German DWA-A 117 guideline, recommended for small rainfall catchments (with an area of 200 ha). A comparative calculation of the retention reservoirs overflow useful volume were conducted for 4 variants of catchment development (degree sealing surface varied from 60% to 90%), under the assumed sewage outflow from the tank at the level of the urban basin natural runoff. At given conditions required unit volume of retention reservoirs, from 145.4 m3 to 206.7 m3 for each 1 ha of catchment area were determined. The obtained results confirmed the fact that useful volume of the tanks were decreased, when Blaszczyk’s pattern reliable rainwater streams were used for calculations. Because the DWA-A 117 guideline method should be applied to a small rainfall catchments, it is recommended to verify the hydraulic capacity of dimensioned channels and objects using hydrodynamic simulations at different load of rainfall catchment scenarios, variable in time and space

Assessing temporal complementarity of solar, wind and hydrokinetic energy

Renewable energy sources (RES) exhibit various characteristics when it comes to their availability in time and space domain. Some are characterised by significant variability and limited predictability. This makes their integration to the power grid a complicated task. Temporal and spatial complementarity of RES is perceived as one of the possible ways to facilitate the process of integration. This paper investigates the concept of temporal complementarity of solar wind and hydrokinetic energy in case of two sites in Poland. Obtained results indicate existence of some beneficial complementarity on inter-annual and annual time scale. Combination of those three RES in one hybrid system makes power source more reliable

Simulating Power Generation from Photovoltaics in the Polish Power System Based on Ground Meteorological Measurements—First Tests Based on Transmission System Operator Data

The Polish power system is undergoing a slow process of transformation from coal to one that is renewables dominated. Although coal will remain a fundamental fuel in the coming years, the recent upsurge in installed capacity of photovoltaic (PV) systems should draw significant attention. Owning to the fact that the Polish Transmission System Operator recently published the PV hourly generation time series in this article, we aim to explore how well those can be modeled based on the meteorological measurements provided by the Institute of Meteorology and Water Management. The hourly time series of PV generation on a country level and irradiation, wind speed, and temperature measurements from 23 meteorological stations covering one month are used as inputs to create an artificial neural network. The analysis indicates that available measurements combined with artificial neural networks can simulate PV generation on a national level with a mean percentage error of 3.2%