Solar Resource Assessment and Meteorology Flashcards
7 cards from real SE ENGR. practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Solar Resource Assessment and Meteorology flashcards as text
In probabilistic solar energy yield analysis, what does a P90 estimate indicate?
Answer: There is a 90% probability that actual energy yield will meet or exceed this value
P90 is the energy yield value with a 90% probability of exceedance, meaning there is a 90% chance actual production will be at or above this level—used by lenders as a conservative estimate.
What is the primary advantage of on-site solar irradiance measurement over relying solely on satellite-derived data?
Answer: Higher temporal and spatial accuracy specific to the local microclimate
On-site measurements capture local microclimatic effects (e.g., coastal fog, valley shading, urban heat islands) that satellite data cannot resolve at fine spatial scales.
According to IEC 61724-1, what is the recommended minimum duration for on-site solar radiation monitoring before commissioning a utility-scale project?
Answer: 12 months
IEC 61724-1 recommends at least 12 months of on-site measurement to capture seasonal variability and validate satellite data for bankable resource assessments.
A sun path diagram is primarily used in solar site assessment to:
Answer: Visualize the sun's position to identify shading obstructions and optimize tilt
Sun path diagrams plot the sun's azimuth and altitude throughout the year, enabling engineers to identify when and where obstructions will cast shadows and to optimize array tilt and orientation.
The term 'insolation' in solar energy engineering refers to:
Answer: Cumulative solar energy received per unit area, typically expressed in kWh/m²/day
Insolation (incident solar radiation) is the time-integrated solar energy received on a surface, expressed in kWh/m² (or equivalent peak sun hours), and is the key metric for estimating PV energy yield.
Which atmospheric condition most strongly increases the diffuse horizontal irradiance (DHI) fraction relative to GHI?
Answer: Increased cloud cover and aerosol loading
Clouds and aerosols scatter direct beam radiation into diffuse radiation, increasing DHI as a fraction of GHI; on overcast days DHI can account for nearly 100% of GHI.
Horizon obstruction analysis in a solar site assessment is performed primarily to:
Answer: Quantify far-field shading losses from terrain, ridges, and distant structures
Horizon obstruction (skyline) analysis maps the elevation of terrain and structures around a site to quantify energy losses from far-field shading, especially critical during low sun angles in winter.