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Abstract: Because of the intermittent nature of the solar radiation resource, photovoltaic (PV) solar energy generation is considered a non-dispatchable power source. However, under some conditions, in sunny urban areas with electricity load curves dominated by air conditioning loads, there is a high correlation between PV generation and utility feeder loads. In these situations, a considerable fraction of a given PV generator can be considered dispatchable power. In this work, we assess the potential of grid connected, building integrated photovoltaic (BIPV) generation in the state capital, Florianópolis, in south Brazil (27°S, 48°W), which is supplied by the local utility company through 56 feeders. Our interest was to identify which feeder could obtain more benefits with implementation of a PV plant with a specific nominal power. Two factors are important in this analysis: the peak demand reduction value, and the LOLP (loss of load probability, in failures per year), or LOLE (loss of load expectation, in hours per year). We analyzed the hourly demand curves of the 56 feeders and compared them with the PV power generation values obtained from a 2kWp BIPV installation that has been operating continuously for nearly 10 years connected to one of these feeders. For our calculations, we defined a PV installation of 1000kWpAC, which corresponds to penetration level values between 10% and 20%, depending on the specific feeder considered. Our results demonstrate that the use of PV power plants can reduce significantly the summer demand peaks in regions where the load reflects commercial customers demand for midday air conditioning. [Copyright &y& Elsevier]

• The five most widely used solar radiation databases were reviewed and compared. • The two most popular PV system sizing software tools were compared. • Hundreds of isolated minigrids in the Amazon are supplied by diesel gen sets with precarious diesel supply. • Combinations of solar radiation database and PV system simulation tools were compared. • Differences in PV sizing and energy generation amounted to over 20% for the same diesel minigrid. • Differences are much more due to solar radiation database than to simulation software. This study evaluated the outcome differences when adopting five different solar irradiation databases on the sizing of hybrid solar photovoltaic-diesel generators designed to supply electricity to isolated minigrids. To do this, the two most widely adopted photovoltaic (PV) simulation packages in the market, namely PVsyst® and HOMER Energy® were used. The different origins, data timespan, space and time resolution, of the five most relevant solar irradiation databases available for the region were compared. A case study was presented to illustrate the influences of the solar irradiation database and the solar simulation tool on the resulting PV generator. Furthermore, the hourly behavior of the energy supply to an existing load in a minigrid in the Brazilian Amazon was evaluated, together with the savings in diesel obtained with the resulting PV generator. Evaluating the five options of solar radiation databases, for the same PV plant configuration, variations of up to 19.7% were found in the expectation of PV generation. When the simulation software package was varied, the combined effect (radiation database X PV system sizing tool) showed differences of up to 20.6%. This demonstrates that despite having different algorithms, computational tools have a small influence (less than 1%) on results. These combined differences, taking into account the load curve behavior and the total diesel generation capacity installed at the site, resulted in over 100% differences in the optimum PV generator size in the case study. The total savings in diesel fuel, over a 15-years period, ranged from $ 6.5 million to over $ 16 million (>2.5 times) for the smallest PV system. This demonstrates the importance of the correct choice of database. These evaluations can be extended to minigrids of any size elsewhere. The novelty and originality of this study is to demonstrate and quantify for the first time the influence of the solar radiation database and the PV simulator package on the sizing of PV-diesel generators. The consequences of this study are not only of scientific and academic importance, but of economic and commercial interest as well. [ABSTRACT FROM AUTHOR]

Abstract: The typical electrical distribution system shows a passive characteristic in relation to power flows (i.e. unidirectional power flows from substation to loads along the feeder). However, with the inclusion of solar photovoltaic (PV) generators along the feeder, this behavior is changed, and characteristics related to power quality, such as voltage level and total harmonic distortion (THD), may be affected. This paper presents the analysis of power quality in a feeder of the urban grid in the city of the Florianopolis, Brazil, with the integration of grid-connected PV systems as distributed generation. The analysis of power quality is based on real measurements of THD on an existing 12kWp PV pilot plant installed in the urban environment, and power flow simulations of a hypothetical PV system of 4.2MWp distributed in the same area, using the ANAREDE software. The power flow simulations allowed assessing the voltage level, the direction of power flow and loading of the distribution lines. The introduction of limited amounts of PV generation as distributed generation in the urban environment was found to be beneficial in several aspects: better voltage profile; power loss reduction and improvement in total harmonic distortion of the voltage (THDv). Furthermore, photovoltaics as a distributed generation source can also postpone feeder capacity upgrading investments. [Copyright &y& Elsevier]

• Solar and wind resources have a relevant temporal complementarity in the Brazilian NE. • Energy mix 40% wind and 60% solar requires minimal storage capacity to supply Brazilian NE load. • Role of storage in reducing the transmission infrastructure needs for renewable energy is evaluated. • Storage increases dispatchability of utility-scale wind and solar power plants. • _______________________________________________________________________________________________ Solar and wind sources together provided more than half of the Brazilian Northeast electricity generation in 2019. This growing share of renewable energies in the Brazilian energy matrix increases the importance of portfolio optimization and the energy storage management. This paper assesses the complementary nature between wind and photovoltaic generation in the Brazilian Northeast, and how this complementarity, together with energy storage, can reduce the shortcomings that the corresponding natural resource intermittency imposes on these sources. The work consists of two main analyses: (i) analysis of the capability in supplying the Brazillian Northeast region power demand with a hybrid wind + solar + storage power plant; and (ii) contingency optimization analysis for hybrid wind + solar + storage power plants. The results show that wind and solar resources are consistently complementary in the region, with a daily Pearson's Correlation Coefficient of −0.51. Also, the load supply analysis shows that a renewable energy mix based on a 40% wind and 60% solar share would require the equivalent of only 6% of its annual generation in storage capacity. An energy curtailment analysis showed that the complementary nature of the wind and solar resources, together with energy storage, can lead to a reduction of up to 11% in transmission capacity demand. [ABSTRACT FROM AUTHOR]