Field Performance of South-Facing and East-West Facing Bifacial Modules in the Arctic

Abstract

This paper presents the first systematic comparison between south-facing monofacial and bifacial photovoltaic (PV) modules, as well as between south-facing bifacial and vertical east-west facing bifacial PV modules in Alaska. The state’s solar industry, driven by the high price of energy and dropping equipment costs, is quickly growing. The challenges posed by extreme sun angles in Alaska’s northern regions also present opportunities for unique system designs. Annual bifacial gains of 21% were observed between side by side south-facing monofacial and bifacial modules. Vertical east-west bifacial modules had virtually the same annual production as south-facing latitude tilt bifacial modules, but with different energy production profiles.

Influence of Selected Working Conditions on Electricity Generation in Bifacial Photovoltaic Modules in Polish Climatic Conditions

“…The difference in power generation of south-facing bifacial panels compared to unilateral panels is about 21%, as reported in the studies conducted in the north of Alaska [22]. Conversely, the vertical installation of double-sided panels in the east-west configuration resulted in the same annual energy generation as in the case of south-facing panels.…”

Energetic Comparison of Vertical Bifacial to Tilted Monofacial Solar

“…Daily soil level as total % power loss was calculated using daily soiling rates specific to the fixed tilt and vertical bifacial systems. The model's default rate of 0.15%/day was found to be appropriate for a 20°fixed tilt panel in the Central Valley, which prior literature suggests is typically 0.108%-0.157%/day [7], [8], [9]. To determine an appropriate rate for the vertical panels, the results of Bhaduri and Kottantharayil [26] were consulted, with the assumption that, though absolute soiling rates may differ between California and Mumbai, the ratio of vertical to 19°fixed tilt results should be similar for similar tilt angles.…”

“…2019 Merced precipitation data from the California Irrigation Management Information System [39] were consulted to identify cleaning events that would reset soil levels. Though the Kimber model selects a default cleaning threshold of 6 mm of rain, Caron and Littmann [7] were able to obtain accurate modeling of their observed 25°tilt system, located in Stratford, with only a 1-mm threshold. With this in mind, the cleaning threshold was set to 1 mm with a 3 day grace period before soiling resumes again.…”

“…These include integration into the outer walls of buildings [5] and incorporation into agrivoltaic farm systems [6], where their extremely low soiling rates compared to inclined systems are of particular benefit, as is the shading offered to sensitive crops. This low soiling of vertical systems also applies to snow loading, and when considered together with the strong dependance on albedo, vertical bifacial panels are particularly attractive for northern climates, such as Alaska, where a combination of east-west oriented vertical panels and south-facing tilted bifacial panels are considered to smooth out daily and annual production profiles [7]. In addition to buildings and agrivoltaic farms, other dual land use applications for bifacial panels include implementation as noise barriers along highways.…”

Three-stage Power Flow & Flexibility Reserve Co-Optimization for Converter Dominated Distribution Network Lookahead Model using Blockchain & S-ADMM — II: Case Study

“…The PV generation forecast at bus i for time t at time t is represented by the state variable 8x f PV i (t, t ). The PV generation forecast is obtained by training the long short-term memory (LSTM) based recurrent neural network model [16] using the historical data from the Suniva OPT270-60-4-1B0 mono facial PV modules installed at a Fairbanks, AK test site [17].…”