|
|
|
Sort Order |
|
|
|
Items / Page
|
|
|
|
|
|
|
| Srl | Item |
| 1 |
ID:
111087
|
|
|
|
|
| Publication |
2012.
|
| Summary/Abstract |
This paper addresses the dual questions: What is the appropriate storage size and its related properties for matching very large photovoltaic plants to the grid; and what are the available technologies for achieving this end. For this purpose a "Usefulness Index" is defined, which, for any grid flexibility, leads to a PV-storage combination that allows high grid-penetration without storage being wastefully large. The paper then examines the sensitivity of this "appropriate storage size" to variations in our assumptions. The specific case of the Israeli electricity grid is employed for numerical discussion, but the formalism should be useful for wider application. In particular, the "appropriate storage size" deduced in this manner is argued to be a valuable point of departure for optimizations of a more sophisticated nature. Regarding available storage technologies, none is found to have all of the required properties for massive PV-grid penetration, but hybrid combinations should be capable of achieving this end.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 2 |
ID:
098563
|
|
|
|
|
| Publication |
2010.
|
| Summary/Abstract |
In this second paper, which studies the hourly generation data from the Israel Electric Corporation for the year 2006, with a view to adding very large-scale photovoltaic power (VLS-PV) plants, three major extensions are made to the results reported in our first paper. In the first extension, PV system simulations are extended to include the cases of 1- and 2-axis sun-tracking, and 2-axis concentrator photovoltaic (CPV) technologies. Secondly, the effect of distributing VLS-PV plants among 8 Negev locations, for which hourly metrological data exist, is studied. Thirdly, in addition to studying the effect of VLS-PV on grid penetration, the present paper studies its effect on grid ramping requirements. The principal results are as follows: (i) sun-tracking improves grid matching at high but not low levels of grid flexibility; (ii) geographical distribution has little effect on grid penetration; (iii) VLS-PV significantly increases grid ramping requirements, particularly for CPV systems, but not beyond existing ramping capabilities; (iv) geographical distribution considerably ameliorates this effect.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 3 |
ID:
098562
|
|
|
|
|
| Publication |
2010.
|
| Summary/Abstract |
We present the results of a number of PV-grid matching simulations performed using hourly generation data from the Israel Electric Corporation (IEC) for the year 2006, together with corresponding meteorological data from Sede Boqer in the Negev Desert. The principal results of this investigation are: (1) the effective flexibility factor (ff) of the IEC grid was close to ff=0.65, but with a different plant operating strategy, ff could have been considerably higher; (2) for ff=0.65, the largest no-dump PV system could have provided only 2.7% of the annual demand, but for higher flexibilities - up to ff=1 - the percentage penetration could be as high as 17.4%; (3) considerable improvement in penetration can result by relaxing the "no-dump" criterion initially imposed on the PV system; (4) using the IEC's existing plant types, additional penetration can be expected by re-scheduling part of the base-load generating capacity to anticipate expected solar input; (5) for a radically decreased grid flexibility - that might result from IEC decisions about future generator purchases - the required employment of massive amounts of storage would render the potential contribution of PV to be insignificant.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4 |
ID:
098561
|
|
|
|
|
| Summary/Abstract |
We present the results of a number of PV-grid matching simulations performed using hourly generation data from the Israel Electric Corporation (IEC) for the year 2006, together with corresponding meteorological data from Sede Boqer in the Negev Desert. The principal results of this investigation are: (1) the effective flexibility factor (ff) of the IEC grid was close to ff=0.65, but with a different plant operating strategy, ff could have been considerably higher; (2) for ff=0.65, the largest no-dump PV system could have provided only 2.7% of the annual demand, but for higher flexibilities - up to ff=1 - the percentage penetration could be as high as 17.4%; (3) considerable improvement in penetration can result by relaxing the "no-dump" criterion initially imposed on the PV system; (4) using the IEC's existing plant types, additional penetration can be expected by re-scheduling part of the base-load generating capacity to anticipate expected solar input; (5) for a radically decreased grid flexibility - that might result from IEC decisions about future generator purchases - the required employment of massive amounts of storage would render the potential contribution of PV to be insignificant.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5 |
ID:
099317
|
|
|
|
|
| Publication |
2010.
|
| Summary/Abstract |
This paper presents a grid matching analysis of wind energy conversion systems (WECSs) and photovoltaic (PV)-WECS hybrid systems. The study was carried out using hourly load data of the Israel Electric Corporation (IEC) for the year 2006 and the corresponding simulated hourly performance of large PV and WECS plants in the Negev Desert. Our major objective was to compare the grid-matching capabilities of wind with those of our previously published PV results, and to assess the extent to which the combined employment of WECS and PV can improve the grid matching capability of either technology when used on its own. We find that, due to the differences in diurnal and seasonal output profiles of WECS and PV, their tandem employment significantly improves grid penetration compared to their use individually.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 6 |
ID:
098609
|
|
|
|
|
| Publication |
2010.
|
| Summary/Abstract |
In this third paper, which studies the hourly generation data for the year 2006 from the Israel Electric Corporation, with a view to incorporating very large photovoltaic (PV) power plants, we address the question: What properties should storage have in order to enhance the grid penetration of large PV systems in an efficient and substantial manner? We first impose the constraint that no PV energy losses are permitted other than those due to storage inefficiency. This constraint leads to powerful linkages between the energy capacity and power capacity of storage, and PV system size, and their combined effect on grid penetration. Various strategies are then examined for enhancing grid penetration, based upon this newfound knowledge. Specific strategies examined include PV energy dumping and baseload rescheduling both on a seasonal basis and shorter time periods. We found, inter alia, that at high grid flexibilities (in the range ff=0.8-1), PV grid penetration levels could be possible in the range 60-90% of annual requirements. Moreover, with appropriately designed storage and accurate forecasting, a future grid could be operated at ff=1.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 7 |
ID:
115146
|
|
|
|
|
| Publication |
2012.
|
| Summary/Abstract |
Recently we reported that PV penetration of up to approximately 90% of the annual demand of the Israeli electricity grid could be achieved using properly sized storage and an appropriate operation strategy. Such a grid clearly requires some conventional generating capacity to be available in order to serve as backup at times when the PV-storage combination alone fails to meet the demand. In the present continuation of that study, we evaluate the largest conventional capacity that would have been required during the one year of data employed for our simulations. For that year, 2006, the required backup capacity for a grid with flexibility ff=0.8 and ff=1 would have been 7.5 GW and 6.6 GW, respectively. This is significantly less than the 10.5 GW of generating capacity that the Israel Electric Corporation operated that year. Our finding emphasizes the fact that a full economic optimization of storage must be based primarily on the engineering-aspects of storage design and use.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|