# Exploring the Benefits of Photovoltaic Non-Optimal Orientations in Buildings
###### Abstract  
As solar photovoltaics in buildings reaches maturity, grid integration and economic yield are topics of greater interest. The traditional design of photovoltaic installations has considered the optimal orientation of photovoltaic modules to be that which yields the maximum annual energy production. The influence of the consumption patterns and the hourly variable electricity prices implies that this traditional optimal design might not be the most profitable. Using a full-year dataset for a residential installation, alternative installations using canopies and modules attached to the facades are simulated. By evaluating the energy balances for different annual consumptions, it is found that the canopy and facade installations offer better self-consumption of the PV produced energy, reflected in a 9% higher self-consumption degree using modules on facades and a 5% higher self-consumption degree using canopies. The economic evaluation under the new electricity tariffs in Spain shows a better profit for PV self-consumption, reducing the time of return on investment by more than 2 years. The analysis of different alternatives for an industrial PV allowed us to identify several benefits for these orientations which are confirmed after a full year of operation, such as an increase of up to 59% in annual energy production over the optimal-producing orientation. solar photovoltaics; PV self-consumption; building-integrated photovoltaics (BIPV); building-applied photovoltaics (BAPV); PV orientations; PV grid integration +
Footnote †: journal: Applied Sciences  
from current levels, and the energy supply mix will be equally divided between renewable and non-renewable sources [7]. Within renewable energies, the breakthrough in solar energy is mainly due to increased efficiency and continued cost reductions [8; 9], and this has led to a worldwide growth in installed solar photovoltaic (PV) capacity [10], increasing by 104% in Europe from 2019 according to SolarPower Europe [11]. In 2020, a year that has been affected by the pandemic, the installed capacity has increased by 11% compared to 2019, reaching 18.2 GW, establishing it as the second best year for PV in Europe, second only to the solar boom in 2011 when 21.4 GW were installed [12]. Spain's current situation in the European environment places is ranked fourth in terms of installed solar capacity, far behind Germany, which is the undisputed leader with more than 48 GW of installed solar capacity. In addition, it also ranks third in terms of solar contribution to total generation in each country, after Germany, which leads the ranking, and Greece. Specifically, 2931 MW were installed in Spain in 2020, reaching a total figure of 11,714 MW, which is equivalent to approximately 11% of total capacity and close to 20% of renewable power. Of these figures, 596 MW of photovoltaic capacity corresponds to self-consumption, where 19% represented domestic self-consumption, nine points above the progress recorded in 2019. The future of photovoltaics in Spain has major goals, which have been consolidated in the National Integrated Energy and Climate Plan 2021-2030 (PNIEC) [13], which proposes a 100% renewable electricity sector by 2050, with an intermediate stage of 74% by 2030. It also adds among its goals to reach a total installed capacity of 44 GW of solar energy by 2030, of which 37 GW will be photovoltaic. In the study of solar installations in buildings, there are two main ways of incorporating PV technology into a building: building-attached photovoltaics (BAPV) and building-integrated photovoltaics (BIPV). In BAPV systems, the PV modules are installed by anchoring them to the building and in BIPV systems, and are part of the building facade, i.e., they serve as building material in the building envelope as multifunctional elements [14]. BIPV is considered one of the four key factors essential for the future success of photovoltaics.