Abstract A two-dimensional version of the Pennsylvania State University mesoscale model has been applied to Winter Monsoon Experiment data in order to simulate the diurnally occurring convection observed over the South China Sea. The domain includes a representation of part of Borneo as well as the sea so that the model can simulate the initiation of convection. Also included in the model are parameterizations of mesoscale ice phase and moisture processes and longwave and shortwave radiation with a diurnal cycle. This allows use of the model to test the relative importance of various heating mechanisms to the stratiform cloud deck, which typically occupies several hundred kilometers of the domain. Frank and Cohen's cumulus parameterization scheme is employed to represent vital unresolved vertical transports in the convective area. The major conclusions are: Ice phase processes are important in determining the level of maximum large-scale heating and vertical motion because there is a strong anvil componen...

Numerical study of convection observed during the Winter Monsoon Experiment using a mesoscale two-dimensional model [presentation]

The paper reviews different approaches, technologies, and strategies to manage large-scale schemes of variable renewable electricity such as solar and wind power. We consider both supply and demand side measures. In addition to presenting energy system flexibility measures, their importance to renewable electricity is discussed. The flexibility measures available range from traditional ones such as grid extension or pumped hydro storage to more advanced strategies such as demand side management and demand side linked approaches, e.g. the use of electric vehicles for storing excess electricity, but also providing grid support services. Advanced batteries may offer new solutions in the future, though the high costs associated with batteries may restrict their use to smaller scale applications. Different “P2Y”-type of strategies, where P stands for surplus renewable power and Y for the energy form or energy service to which this excess in converted to, e.g. thermal energy, hydrogen, gas or mobility are receiving much attention as potential flexibility solutions, making use of the energy system as a whole. To “functionalize” or to assess the value of the various energy system flexibility measures, these need often be put into an electricity/energy market or utility service context. Summarizing, the outlook for managing large amounts of RE power in terms of options available seems to be promising.

https://research.aalto.fi/files/6557604/lund_et_al_review.pdf

Review of energy system flexibility measures to enable high levels of variable renewable electricity

Machine learning methods for solar radiation forecasting: A review

Review of photovoltaic power forecasting

http://coimbra.ucsd.edu/publications/papers/2013_Inman_Pedro_Coimbra.pdf

Solar forecasting methods for renewable energy integration

The contribution of power production from PV systems to the electricity supply is constantly increasing. An efficient use of the fluctuating solar power production will highly benefit from forecast information on the expected power production, as a basis for management of the electricity grids and trading on the energy market. We present and evaluate the regional PV power prediction system of University of Oldenburg and Meteocontrol GmbH providing forecasts of up to 2 days ahead with hourly resolution. The proposed approach is based on forecasts of the global model of the European Centre for Medium-Range Forecasts (ECMWF). It includes a post-processing procedure to derive optimised, site-specific irradiance forecasts and explicit physical modelling steps to convert the predicted irradiances to PV power. Finally, regional power forecasts are derived by up-scaling from a representative set of PV systems. The investigation of proper up-scaling is a special focus of this paper. We introduce a modified up-scaling approach, modelling the spatial distribution of the nominal power with a resolution of 1° × 1°. The operational PV power prediction system is evaluated in comparison to the modified up-scaling approach for the control areas of the two German transmission system operators ‘transpower’ and ‘50 Hertz’ for the period 2.7.2009–30.4.2010. rmse values of the operational forecasts are in the range of 4–5% with respect to the nominal power for intra-day and day-ahead forecast horizons. Further improvement is achieved with the modified up-scaling approach. Copyright © 2010 John Wiley & Sons, Ltd.

Regional PV power prediction for improved grid integration

Power generation from photovoltaic systems is highly variable due to its dependence on meteorological conditions An efficient use of this fluctuating energy source requires reliable forecast information for management and operation strategies Due to the strong increase of solar power generation the prediction of solar yields becomes more and more important As a consequence, in the last years various research organisations and companies have developed different methods to forecast irradiance as a basis for respective power forecasts For the end-users of these forecasts it is important that standardized methodology is used when presenting results on the accuracy of a prediction model in order to get a clear idea on the advantages of a specific approach In this paper we introduce a benchmarking procedure to asses the accuracy of irradiance forecasts and compare different approaches of forecasting The evaluation shows a strong dependence of the forecast accuracy on the climatic conditions For Central European stations the relative rmse ranges from 40 % to 60 %, for Spanish stations relative rmse values are in the range of 20 % to 35 %

/pdf/benchmarking-of-different-approaches-to-forecast-solar-1zqv356am7.pdf

Benchmarking of different approaches to forecast solar irradiance

Local and regional photovoltaic power prediction for large scale grid integration: Assessment of a new algorithm for snow detection

Knowledge of the solar energy resource is essential for the planning and operation of solar energy systems. In past years there has been substantial European and national funding to develop information systems on solar radiation data, leading to the situations that several data bases exist in parallel, developed by different approaches, various spatial and temporal coverages and resolutions including those exploiting satellite data. The user of these products may end up with different results for the same requested sites. To better guide the users, a benchmarking exercise is under preparation. A set of reference data has been collected and benchmarking measures and rules have been defined. The results of the benchmarking and the feedback from stakeholders will be integrated into a guide of best practices in the application of solar resource knowledge. Access to data has been quite fragmented. Each service has its own way of access to the data and delivery format. A new broker portal based on the experience of the project Soda aims to unify and ease the access to distributed data sources and applications providing solar resource information.

/pdf/management-and-exploitation-of-solar-resource-knowledge-23jw9cz5tw.pdf

Management and Exploitation of Solar Resource Knowledge

Knowledge of solar energy resource has been generated over the past years within several European and national projects. Large steps forward have been made for the benefit of research, renewable energy industry and the environment. Nevertheless, these multiple efforts have led to a fragmentation and uncoordinated access: different sources of information and solar radiationproducts are now available, but uncertainty about their quality remains. At the same time, communities of users lack common understanding how to exploit the developed knowledge. The project MESoR aims at removing the uncertainty and improving the management of the solar energy resource knowledge. The results of past and present large-scale initiatives in Europe, will be integrated, standardised and disseminated in a harmonised way to facilitate their effective exploitation by stakeholders. This coordination action will contribute to preparation of the future roadmap for RD handbook; best practices), unification of access to information (use of advanced information technologies; offering one-stop-access to several databases), connecting to other initiatives (INSPIRE of the EU, POWER of the NASA, SHC and PVPS of the IEA, GMES/GEO) and to related scientific communities (energy, meterology, geography, medicine, ecology), and dissemination (stakeholders involvement, training, future R&D, communication). To that purpose, a consortium has been assembled that gathers several partners having co-ordinated large international projects in the domain and other partners bringing the necessary expertise to the achievement of the objectives. The consortium provides a unique interface/ point of contact for the renewable energy community for retrieving data necessary to establish solar renewables as fully competitive energy option.

/pdf/mesor-management-and-exploitation-of-solar-resorce-knowledge-3kdex3z1w1.pdf

Christian Kurz

Papers

Regional PV power prediction for improved grid integration

Benchmarking of different approaches to forecast solar irradiance

Local and regional photovoltaic power prediction for large scale grid integration: Assessment of a new algorithm for snow detection

Management and Exploitation of Solar Resource Knowledge

MESoR - Management and exploitation of solar resorce knowledge