Abstract
In this paper, we analyze the sensitivity of the optimal mixes to cost and variability associated with solar technologies and examine the role of Thermal Energy Storage (TES) combined to Concentrated Solar Power (CSP) together with time-space complementarity in reducing the adequacy risk—imposed by variable Renewable Energies (RE)—on the Moroccan electricity system. To do that, we model the optimal recommissioning of RE mixes including Photovoltaic (PV), wind energy and CSP without or with increasing levels of TES. Our objective is to maximize the RE production at a given cost, but also to limit the variance of the RE production stemming from meteorological fluctuations. This mean-variance analysis is a bi-objective optimization problem that is implemented in the E4CLIM modeling platform—which allows us to use climate data to simulate hourly Capacity Factors (CFs) and demand profiles adjusted to observations. We adapt this software to Morocco and its four electrical zones for the year 2018, add new CSP and TES simulation modules, perform some load reduction diagnostics, and account for the different rental costs of the three RE technologies by adding a maximum-cost constraint. We find that the risk decreases with the addition of TES to CSP, the more so as storage is increased keeping the mean capacity factor fixed. On the other hand, due to the higher cost of CSP compared to PV and wind, the maximum-cost constraint prevents the increase of the RE penetration without reducing the share of CSP compared to PV and wind and letting the risk increase in return. Thus, if small level of risk and higher penetrations are targeted, investment must be increased to install more CSP with TES. We also show that regional diversification is key to reduce the risk and that technological diversification is relevant when installing both PV and CSP without storage, but less so as the surplus of energy available for TES is increased and the CSP profiles flatten. Finally, we find that, thanks to TES, CSP is more suited than PV and wind to meet peak loads. This can be measured by the capacity credit, but not by the variance-based risk, suggesting that the latter is only a crude representation of the adequacy risk.
Highlights
Climate mitigation in the energy sector, as well as the global increase of the energy demand are the main drivers of an energy transition towards Renewable Energies (REs) technologies
We examine common features for all combinations which help understand the general behavior of the model, draw insights on the sensitivity of the optimal mixes to the cost of solar technologies and the Concentrated Solar Power (CSP)’s Solar Multiple (SM), and evaluate the effect of Thermal Energy Storage (TES) and of correlations between Capacity Factors (CFs)—for different zones and/or technologies—on the risk adequacy
We study the response of regional Renewable Energy (RE) mix—including Solar Photovoltaic (PV)
Summary
Climate mitigation in the energy sector, as well as the global increase of the energy demand are the main drivers of an energy transition towards Renewable Energies (REs) technologies. Among the RE sources, solar energy is one of the most promising source to replace fossil fuels in meeting the world’s future energy needs [1]. There are two main ways for converting solar energy into electricity: Solar Photovoltaic (PV) and Concentrated Solar Power (CSP). For any particular power system, RE portfolios including these solar technologies are likely to result in different patterns of cost, mean production and variability, which have a great influence in the decision whether PV or CSP or CSP with Thermal Energy Storage (TES), hereafter referred as CSP-TES, should be employed Suited sites for CSP are distributed along the descending branches of the Hadley cells in the subtropical arid regions, which display minimum cloud cover and maximum direct solar radiation, in the Middle East and North African countries [3,4,5], leading to a reduced cost of the CSP MWh in this region compared to Spain [6], the country with the world’s largest CSP capacity in 2018.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
