Effects of temporal averaging on short-term irradiance variability under mixed sky conditions
| dc.contributor.author | Lohmann, Gerald M. | |
| dc.contributor.author | Monahan, Adam H. | |
| dc.date.accessioned | 2019-09-13T19:30:10Z | |
| dc.date.available | 2019-09-13T19:30:10Z | |
| dc.date.copyright | 2018 | en_US |
| dc.date.issued | 2018 | |
| dc.description.abstract | Characterizations of short-term variability in solar radiation are required to successfully integrate large numbers of photovoltaic power systems into the electrical grid. Previous studies have used ground-based irradiance observations with a range of different temporal resolutions and a systematic analysis of the effects of temporal averaging on the representation of variability is lacking. Using high-resolution surface irradiance data with original temporal resolutions between 0.01 and 1 s from six different locations in the Northern Hemisphere, we characterize the changes in representation of temporal variability resulting from time averaging. In this analysis, we condition all data to states of mixed skies, which are the most potentially problematic in terms of local PV power volatility. Statistics of clear-sky index k* and its increments Δk*τ (i.e., normalized surface irradiance and changes therein over specified intervals of time) are considered separately. Our results indicate that a temporal averaging time scale of around 1 s marks a transition in representing single-point irradiance variability, such that longer averages result in substantial underestimates of variability. Higher-resolution data increase the complexity of data management and quality control without appreciably improving the representation of variability. The results do not show any substantial discrepancies between locations or seasons. | en_US |
| dc.description.reviewstatus | Reviewed | en_US |
| dc.description.scholarlevel | Faculty | en_US |
| dc.description.sponsorship | All calculations were performed at the HPC Cluster CARL, located at the University of Oldenburg (Germany) and funded by the DFG through its Major Research Instrumentation Programme (INST 184/157-1 FUGG) and the Ministry of Science and Culture (MWK) of the state of Lower Saxony.We thank Stefan Harfst at the University of Oldenburg for his support with the cluster. This research was partially funded by the Lower Saxony research network “Smart Nord”, which acknowledges the support of the Lower Saxony Ministry of Science and Culture through the “Niedersächsisches Vorab” grant program (grant ZN 2764/ZN 2896). It was also partly funded by the “Performance Plus” research project through the European Union’s Seventh Framework Program for research, technological development and demonstration (grant agreement no. 308991). We also acknowledge funding from the Government of Canada through the ecoENERGY Innovation Initiative (ecoEII) to collect the data in Alderville and Varennes, as well as funding support from the Natural Sciences and Engineering Research Council of Canada. | en_US |
| dc.identifier.citation | Lohmann, G.M. & Monahan, A.H. (2018). Effects of temporal averaging on shortterm irradiance variability under mixed sky conditions. Atmospheric Measurement Techniques, 11(5), 3131-3144. https://doi.org/10.5194/amt-11-3131-2018 | en_US |
| dc.identifier.uri | https://doi.org/10.5194/amt-11-3131-2018 | |
| dc.identifier.uri | http://hdl.handle.net/1828/11136 | |
| dc.language.iso | en | en_US |
| dc.publisher | Atmospheric Measurement Techniques | en_US |
| dc.title | Effects of temporal averaging on short-term irradiance variability under mixed sky conditions | en_US |
| dc.type | Article | en_US |