Many homeowners know that investing in solar energy can lower their energy bills and reduce their environmental impact. However, many people do not know exactly how solar panels work . Knowing the science behind solar technology can help you make better decisions when purchasing a system from a major solar company . This article contains important information about solar panels , how they work, and the components that support a solar energy system .
What are solar panels?
Solar panels are devices that power your home by converting the sun's energy into usable electricity . Also known as photovoltaic (PV) solar panels, they provide renewable energy for your home without the need for expensive and toxic fossil fuels . Photovoltaic panels are usually installed on the roof, but ground-mounted installations are also available. The number of panels you need depends on your energy consumption, the type of solar panel you choose and the available space.
Cloudless sunny days are ideal for solar panels and provide maximum power. The panels work on cloudy days , but the power output is reduced. The shadows of nearby buildings or trees can interfere with your solar system.
What is the photoelectric effect?
The science behind solar panels is known as the photovoltaic effect . Sunlight particles, or photons , knock electrons out of atoms . When these electrons are in motion, the solar panels capture the current and generate electricity .
The panels contain components known as photovoltaic (PV) cells that collect sunlight. Photovoltaic cells are typically six inches long and six inches wide. A typical panel has 32 to 48 photocells, but this number can vary depending on the size and power of the panel. Inside each cell is a metal semiconductor material that helps absorb energy . In traditional solar panels , this material is silicon, one of the most abundant elements on earth.
Silicon itself is not a good conductor. Solar manufacturers use a process called "doping" to improve silicon's conductivity and bind impurities. Two elements are added to create an electric charge: boron and phosphorus . Boron adds a positive charge while phosphorus adds a negative charge .
These elements are placed on two layers of silicon and create an electric field together . The sides of silicon solar cells are covered with metal plates that help push electrons through the wire as an electric current . This current travels through the rest of the solar panel and into your home .
Types of materials for solar panels.
The most popular solar panels use crystalline silicon. These panels are of two types: monocrystalline (mono) and polycrystalline (poly).
Monopanels use monocrystalline technology. Their price is higher than other types of panels but they provide the highest power and efficiency. Polypanels use broken crystal lines, which is a more economical process, because the split silicon can be used to produce more panels. Polyethylene panels have a low price, but they have less power.
Thin film solar panels are a cheaper alternative to glass panels. They use thin photovoltaic materials instead of silicon. Although thin film panels are cheaper, they provide the lowest energy consumption of the three options.
Efficiency of solar panels.
These different manufacturing processes will affect the efficiency level of your solar panels . Efficiency measures how much sunlight a panel absorbs and how efficiently it converts sunlight into solar energy . The higher the efficiency level, the higher the solar energy conversion of the panel. For example, a solar panel with an efficiency rating of 20% can absorb 20% of the sunlight falling on it. The National Renewable Energy Laboratory (NREL) reported today that solar panels provide an efficiency of 16% to 22%, but average around 19.2%.
Monocrystalline panels using refined silicon provide the highest level of efficiency, typically 17-23%. Polycrystalline panels fall a little lower, the rating ranges from 13% to 16%. Thin film panels have the lowest efficiency between 7% and 11%.
Understanding how solar panels work
Each component of your solar energy system plays a critical role in energy conversion. Below is a step-by-step guide on how to make your own solar panels .
- Solar energy activates the photovoltaic cells : then the photovoltaic effect begins . When sunlight hits the solar panel , the photovoltaic cells are activated and capture the rays . Panels convert this energy into electricity . Initially, the power is converted to DC or DC electricity .
- DC electricity is converted to AC electricity . A solar inverter converts DC electricity into AC electricity which is used in every home. Inverter installation is divided between two types: string and micro inverters . String inverters , the most common type, are installed in your home and convert electricity from all your solar panels in one central location. Microinverters are installed on each panel , which converts the energy in the source of generation.
- AC electricity reaches your home: After it is converted to AC power, it enters your home through the electrician and into your electrical outlets. This process is similar to receiving electricity from a utility through the power grid . Some homeowners keep their solar systems connected to the grid so that their home receives electricity when the panels are not in use . However, you can only run your house with solar energy . To go offline at night or on days with little sunlight, you need to build a backup power system to meet your home's needs.
- Grid Meter Monitors and Controls Energy: As your system generates solar energy , the grid meter monitors the usage of all grid -connected systems. This device monitors the power generated by your system and the amount of electricity drawn from the grid. Net metering tracks the excess power generated by your system . If your state or local government offers a net metering program, you can sell that excess energy back to the grid for utility credits or annual payments. These loans help offset electricity bills when you need electricity. For more information on how to find net metering programs in your area , see the State Incentives for Renewable Energy and Efficiency (DSIRE) database .
- Solar systems store excess electricity . If your area doesn't have a grid-metering program, or if you want to save too much energy, you can add a solar panel to your system. Solar panels store extra energy until they are ready for use. This is useful in case of unexpected power outages and other solar panels are not working. In some areas, stored electricity may be available at higher electricity prices, further reducing utility bills. You can add solar energy storage options to a new or existing grid.
Our advice
The success of any solar system starts with the panels. We recommend investing in high quality solar panels to maximize your savings and return on investment. Consider solar incentives , such as federal tax credits , to reduce installation costs . When shopping for a solar system, compare offers from at least three installers to find the best options. Below we have provided a tool to help you start your search.
