Solar Power for electricity and heat generation has become a widely used source of alternative energy for a while. Solar power is an expensive investment; therefore it requires some feasibility study based on accurate simulations. Since actual solar power at any location and time is a very strong function of weather conditions, one can not predict it exactly. A cloudy day can bring the harvested solar energy to 10% of a sunny day at the same location. Therefore one has to be first able to calculate the “maximum possible solar energy at any given time and for any time interval at any location” and factor in the weather conditions for a good feasibility analysis.
The most of the commonly employed solar power calculation methods today are based on empirical “Air Mass” formulas using sun’s elevation angle. They are wavelength independent and fail to predict the solar power received at the solar power converter, like solar panel or solar cell for any altitude and especially for lower sun elevation angles accurately. Moreover they also don’t take into consideration of optical losses of the solar module which is related to the incidence angle of the sun with respect to the solar panel normal along with its optical properties all the way to the solar cell, which can be quite significant for fixed panels. This optical loss in the panel is greatly reduced for sun tracking solar panels, but still is significant. In addition, very few sun position algorithms are accurate for “any date” at latitudes higher than 68 degrees. A large portion of the places where solar power is utilized are at higher altitudes where “curve-fit” approximations highly over estimate the solar power.
SolarPower uses proven patent pending “OEA Astronomical and Navigational Utilities” to calculate the sun’s position very accurately in seconds on a smart phone, with an incredible accuracy of 0.0003 degrees anywhere on earth, at any altitude, from the South Pole to the North Pole, at any date and time, past future or present! This is the first requirement of having accurate solar power prediction.
SolarPower calculates atmospheric attenuation of solar radiation by the numerical solution of the Maxwell’s equations taking the wave-length dependent absorption and Raleigh scattering in the atmosphere into consideration for the entire solar spectrum. Planck radiation law is used to calculate the spectral power density distribution of the sun light in the upper atmosphere, which gives the initial value of the problem. This approach gives very accurate prediction of the entire solar power spectrum at any sun elevation angle accurately, from sun rise to sun set for any altitude.
SolarPower gets the “actual” position and time from GPS. In addition to this mode it also can do “virtual” simulation any where on earth at any date using its advanced global mapping capabilities. With GPS, magnetic compass and the inclinometer capabilities of the smart phone the panel orientation is obtained by just a touch of a button with many easy to use options. After a “real time” short simulation SolarPower will give the solar power, solar energy for any selected day, month or the entire year. The generated electrical energy and power is calculated by multiplying the received solar power with the user defined panel conversion efficiency.
SolarPower gives many useful, easy to understand graphics for power, energy, solar spectrum, atmospheric path length, sun elevation and azimuth variation during the day. The user can quantify and compare the optical loss between tracked and fixed panels.
SolarPower produces the daily and monthly comparative plots for tracked versus fixed solar panels any where on earth both graphically and in table form. As a bonus, it also has GPS tracking, moon phase and positioning, planet location capabilities from anywhere on earth for any date supporting 39 languages.
(Continued use of GPS running in the background can dramatically decrease battery life)