Renewable Energy Systems Flashcards
7 cards from real Certified Energy Auditor Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Renewable Energy Systems flashcards as text
What is the 'capacity factor' of a renewable energy system?
Answer: The ratio of actual energy output over a period to the maximum possible output at full rated capacity
Capacity factor is the ratio of actual energy produced to the maximum possible energy if the system operated at full rated capacity continuously over the same period.
Which unit is used to measure solar irradiance?
Answer: W/m²
Solar irradiance is the instantaneous power of solar radiation per unit area, expressed in watts per square meter (W/m²).
What is the primary difference between photovoltaic (PV) and solar thermal systems?
Answer: PV systems convert sunlight directly to electricity while solar thermal captures solar heat energy
Photovoltaic systems directly convert solar radiation to electricity via the photovoltaic effect, while solar thermal systems capture solar energy as heat for water or space heating applications.
What are Standard Test Conditions (STC) for rating photovoltaic panels?
Answer: 25°C cell temperature, 1000 W/m² irradiance, and AM 1.5 spectrum
STC defines PV panel performance at 25°C cell temperature, 1000 W/m² irradiance, and AM 1.5 solar spectrum, providing a universal standard for comparing module wattage ratings.
In net metering, what happens when a facility's renewable energy system produces more electricity than the facility consumes?
Answer: The excess electricity is credited to the customer's bill at retail rates
Net metering allows customers to receive bill credits at retail rates for excess electricity fed back to the grid, which offset future electricity charges.
What is a Solar Renewable Energy Certificate (SREC)?
Answer: A tradeable certificate representing 1 MWh of electricity generated from solar energy
An SREC represents 1 MWh of solar electricity generated and can be sold separately from the electricity itself to utilities needing to meet Renewable Portfolio Standards.
Which factor most significantly reduces actual PV energy output compared to STC-rated output?
Answer: Aggregate system losses including temperature derating, wiring, inverter efficiency, and soiling
Aggregate system losses—temperature derating, wiring resistance, inverter efficiency, soiling, and mismatch—typically reduce real-world output by 20–30% compared to STC ratings.