How Important is Location Factor for Wind and Solar?
How location factor impacts Wind power
A wind turbine essentially obtains power by converting the force of the wind into a torque on the rotor blades. Three important location factors that govern the amount wind energy transferred to the rotor are the 1) Altitude of turbine i.e. the height of tower 2) The density of the air and 3) The wind shear.We'll explain each of these factors below:
Height of Tower
Wind speed depends on height of the turbine from the ground. Clearly, productivity increases by 34% if the height of the windmill is doubled. This is because at a greater height wind blows fast and freely as there are less climatic disturbances in the atmosphere and less obstructions as compared to the ground which is full of obstructions in the form of buildings, houses, trees, etc.
The kinetic energy in the wind is a function of density of the air. If the air is heavy, then the turbine receives more energy. Humid climates have greater air density than dry climates hence wind plants function better near oceans and seas. At higher altitude, air density lessens dramatically; hence it is impossible to make wind farms in the mountains.
Wind shear and roughness factor
The fact that the wind profile is twisted towards a lower speed as we move closer to ground level is called as Wind Shear.
As is clear from the figure above that the more pronounced the roughness of earth’s surface, the more the wind will be slowed down and hence less power. A high roughness class of 3-4 refers to landscapes that have many obstacles like trees and skyscraper buildings while a roughness class of zero means sea surfaces and oceans that have zero obstructions hence roughness class of zero.
How location factors impact the solar panels
For installation of a solar PV system, it is very important to evaluate the location where the system will be installed. Even the best solar panels with the highest efficiency in the market, will not give good output if the location has poor conditions for photovoltaics. The location criteria important for efficient functioning of the PV are explained below.
Does the location have a good Solar Radiation?
Solar potential of a place influences the energy output of a photovoltaic system. Since our Earth is round, some locations receive higher amounts of insolation than others. In general, region around tropics are much more favorable than locations around poles. It is important that a selected site should be exposed to some minimum threshold of solar radiation on a daily basis per year.
Are there obstacles in the path of sunlight?
It is important to check if the place of location of PV unit has obstacles that can block a considerable portion of sunlight hence lowering the optimal functioning of the system. Some important obstacles to watch out for before installing a PV system at a location include:
1) Panel systems should not be in the vicinity of tall buildings. The productivity of a solar PV system lessens if the power generation unit is around tall structures and skyscrapers. This is because the large shadows cast by structures can impede the sunrays and reduce the efficiency of PV system production considerably.
2) One must check for the presence of mountains nearby. Since incident sunlight in northern hemisphere comes from the southern part of sky, any mountains in south of installed PV can block the sunlight hence reducing the productivity of panels.
3) Check for the location of Trees. Tall trees and bushes can cast shadows and become a barrier for sunlight. As the solar arrays connect in series, a single panel facing shadows can negatively impact the energy production of the entire PV system.