Solar Energy Fundamentals Flashcards
Use this deck to learn about all of the solar energy aspects of a PV system installation.
What is proportional to the energy used?
The length of time a load is on
When does the sun set in the same place on the horizon?
At winter solstice
The azimuth of solar (true) south is -24 of a magnetic compass in San Francisco, CA. Your array is aiming to the heading of what degree?
189 degrees
When the sun sets on summer solstice, which direction is the farthest that it will ever set?
North
At what point is it the same day everywhere in the world at the same time?
Equinox
In St. Paul MN, is the sun up the same amount of hours as there are sun hours per day?
No
How does the amount of sun falling on higher elevations compare to lower elevations?
Greater
If a site gets an average of 5.3 sun hours per day according to the National Renewable Energy Laboratories for a particular city and the home uses 10 kilowatt hours per day on average, what size grid-tied, net metered system would most closely offset the energy usage?
2.45 kw PV system
When is the sun farthest north?
Summer solstice
What surfaces of the earth receive the most amount of sun?
Surfaces at higher elevations
In Oakland, California, the sun will never do what?
Have a zenith angle of zero
In St. Paul MN, how many hours is the sun up, compared with the number of sun hours per day?
More hours
When irradiance increases what happens to the I-V curve?
The curve shifts up
The altitude angle is the angle of what?
The angle from zenith to the horizon
What is an example of solar irradiation?
5.5 sun hours per day
What is sinusoidal, bimodal, and indirect energy in an off-grid system?
Solar and wind energy
5.5 sun hours is an example of what?
Solar irradiation
What is an equinox?
The time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length
Are solar power, unit area, and solar efficiency, time factors for insolation measurement?
No
Every year the sun does what on the winter solstice?
The sun sets in the same place on the horizon
A water pump only pumps when the sun is out, by tilting the array more than the latitude angle, what amount of water do you pump?
Pump the same amount of water every month during the year
You can use what to account for colder temperatures causing higher voltage?
A temperature correction factor, weather trends that include record low temperatures, and/or a typical string sizing program from an inverter manufacturer found on the internet
What is more prevalent in isolated communities?
Battery based systems
In locations with what kind of latitude does the sun rise further to the north in the winter?
Higher latitudes
