Shading, even if partial, can be detrimental to the outcome of solar power systems. Having trees around a house means the possibility of shadows cast on certain parts of the rooftop solar panels. The presence of shade on the rooftop can compromise the energy output of the solar installation.
Why Does Shading Impact Rooftop Solar Energy Production?
Most solar photovoltaic systems contain solar panels (array) and a solar inverter. While solar panels convert sunlight into DC electricity, the solar inverter then converts it into AC electricity, which is compatible with the grid and appliances. Due to the voltage requirements of a PV system’s inverters, solar arrays are divided into ‘strings’ of solar panels. Solar power, once generated, flows through the strings of panels.
Shade can block the flow of solar power through the string, preventing homeowners from realizing the full benefits of the costly solar panels they install. Shade from trees and chimneys on even a single solar panel in a string can reduce or flatten the output.
How to Harness Solar Power for a House Nestled in Trees?
There are ways in which house owners can deal with the problem of shading of solar arrays in case their house is nestled in trees:
1. Bypass Diodes
Innovative instruments used on photovoltaic (PV) systems such as Bypass Diodes are installed to protect partially shaded PV cells and mitigate the destructive effects of cell shading. These devices are connected externally and in reverse parallel to provide an alternative electrical path for the generated current to flow through. They preserve the performance of the series string to maintain the optimal output of electrical energy.
2. String Inverter with Global MPPT
House owners with partially shaded rooftops must choose a solar inverter that performs global MPPT for optimum energy production. String inverters on solar panels also determine the voltage and current levels at which the array operates. In a partially shaded array, inverters skip shaded sections instead of running at their lower current with the use of Bypass Diodes. Thus, multiple operating points maximize power output in a solar installation on partially shaded roofs. A string inverter with Global MPPT sweeps across the full range of current and voltage levels to determine which power output is globally maximized.
3. Solar Micro Inverters and Power Optimizers
Micro inverters and power optimizers are used to improve performance for solar panels on roofs that experience marginal shading during the day. Micro inverters are a small version of an inverter that converts DC to AC power from an individual solar panel. It can optimize the power production from each individual module to deliver maximum energy from the solar array.
Sometimes, when each module has an MPPT but only one system inverter, solar experts recommend a power optimizer for each panel to convert its optimum DC output to the inverter’s optimum DC power.
A simple site survey by a solar expert, including the shading analysis, can help you figure out how to harness solar power for a house nestled in trees.
We at nationalsolarcompany.com.au deal with solar inverters, solar panels, and solar batteries to cater to your all-around solar energy needs.