We all know that solar photovoltaic (PV) panels transform sunlight into usable electricity, but few people know the actual science behind the process. On the blog, we are going to delve into the intricate science behind solar. It can seem complicated, but it all boils down to the photovoltaic effect; the ability of matter to emit electrons when exposed to light.
Basic Steps in Solar Energy Generation and Transmission
- Sunlight hits the solar panels and creates an electric field.
- The electricity generated flows to the edge of the panel, and into a conductive wire.
- The conductive wire brings the electricity to the inverter, where it is transformed from DC electricity to AC, which is used to power buildings.
- Another wire transports the AC electricity from the inverter to the electric panel on the property (also called a breaker box), which distributes the electricity throughout the building as needed.
- Any electricity not needed upon generation flows through the utility meter and into the utility electrical grid. As the electricity flows through the meter, it causes the meter to run backward, crediting your property for excess generation.
Now that we have a basic idea of the generation and flow of solar electricity, let’s take a deeper dive into the science behind the solar photovoltaic panel.
The Science Behind Solar PV Cells
Solar PV panels are comprised of many small photovoltaic cells – photovoltaic meaning they can convert sunlight into electricity. These cells are made of semi-conductive materials, most often silicon, which can conduct electricity while maintaining the electrical imbalance needed to create an electric field.
When sunlight hits the semiconductor in the solar PV cell, the energy from the light, in the form of photons, is absorbed, knocking loose several electrons, which then drift freely in the cell. The solar cell is specifically designed with positively and negatively charged semiconductors sandwiched together to create an electric field. This electric field forces the drifting electrons to flow in a certain direction- towards the conductive metal plates that line the cell. This flow is known as an energy current, and the strength of the current determines how much electricity each cell can produce. Once the loose electrons hit metal plates, the current is then directed into wires, allowing the electrons to flow like they would in any other source of electric generation.
As the solar panel generates an electric current, the energy flows through a series of wires to an inverter. While solar panels generate direct (DC) electricity, most consumers need alternating (AC) electricity to power their buildings. The inverter’s function is to turn the electricity from DC to AC, making it accessible for everyday use.
After the electricity is transformed into a usable state (AC power), it is sent from the inverter to the electrical panel (also called a breaker box) and distributed throughout the building as needed. Electricity is now readily available to power lights, appliances, and other electrical devices with solar energy.
Any electricity that is not consumed through the breaker box is sent to the utility grid via the utility meter. The utility meter measures the flow of electricity from the grid to your property and vice versa. When your solar energy system is producing more electricity than you are using on-site, this meter runs backward, and you are credited for the excess electricity generated through the process of net metering. When you are using more electricity than your solar array is generating, you draw supplemental electricity from the grid through this meter, making it run normally. Unless you have gone completely off-grid with a storage solution, you will need to draw some energy from the grid, especially at night, when your solar array is not producing. However, much of this grid energy will be offset by the excess solar energy you generate throughout the day and in periods of lower usage.
While the details behind solar are highly scientific, it doesn’t take a scientist to convey the benefits a solar installation can bring to a business or property owner. An experienced solar developer can walk you through these benefits and help you explore if a solar solution is right for your business.
Top four benefits of installing solar panels on your home
Solar panels are a great way to offset energy costs, reduce the environmental impact of your home and provide a host of other benefits, such as supporting local businesses and contributing to energy independence.
Looking to install panels on your home? Here’s presenting the top four benefits.
1. Reduce or eliminate energy bills
This one is pretty amazing. In many regions which have an average amount of sun, just enough to power our house of three kids and two adults at net zero energy consumption. On warm spring days, one can generate a lot more than one consumes, and then the remaining can be traded with the utility. On hot summer days, when we run the air conditioning, or on cloudy days, we draw from the grid.
Even if you live somewhere cloudy, such locations typically receive more than two hours of sunlight per day, while sunny locations receive an average of 5.5 hours of sunlight per day.
Although sunny days will produce more solar energy, solar panels will continue to draw energy even when the weather is cloudy. Indirect, or diffused, sunlight will still help to power your home. Cloudy days usually produce around 10 to 20 percent of the power generated on sunny days.
2. Earn tax credits and rebates
To start, you will get 30 percent of total system costs back from equipment and installation as a federal income tax credit when you file your taxes. This means you would save $7,500 on a solar system worth $25,000.
Combine this with state and local rebates and Solar Renewable Energy Credits (SRECs), the total costs can be cut in half. The SRECs are generated throughout the year, and you can sell them to utility companies, which generates an awe-inspiring return on the initial investment.
3. Start saving from day one
Annual energy costs can be in the thousands. The average annual energy expenditure per person is $3,052, including transportation and residential energy. Solar power can reduce or eliminate these costs as soon as they are installed. They also offer long-term savings, because it’s free to capture the power of the sun.
Solar panels significantly improve your resale value. Most home buyers understand what a home with solar panels means, especially because the system is already in place, and they didn’t have to make the initial investment and installation. According to research, most homeowners see an increase in resale value increase per installed kilowatt. That means if you install over a 3-kilowatt system, you could improve your home’s resale value by many thousands.
Solar panels also extend the life of a roof, because they protect it from the elements, such as rain, snow, and debris. They make the house more energy-efficient in the summer because the hot sun is not beating down on the roof directly—it is instead being absorbed by the panels, keeping the house temperature lower.
4. Help the environment and help us all
Solar power systems derive clean, pure energy from the sun. Installing solar panels in your home helps combat greenhouse gas emissions and reduces our collective dependence on fossil fuels. Traditional electricity is sourced from fossil fuels such as coal and natural gas. When fossil fuels are burned to produce electricity, they emit harmful gases that are the primary cause of air pollution and global climate change. Not only are fossil fuels bad for the environment, but they are also finite resources. Because of this, the price is constantly fluctuating and can increase in a short period.
Renewable energy also improves public health. Coal and natural gas plants produce air and water pollution that is harmful to human health. But replacing fossil fuels with renewable energy sources, such as solar power, can reduce premature mortality as well as overall health care costs.
Although fossil fuel production requires significant water resources and causes water pollution, solar energy requires little to no water to operate. So, not only does solar power not pollute water resources, but it also doesn’t put a strain on the world’s water supply.
Solar power also works during a drought or heat wave. Coal, natural gas, and nuclear power use large amounts of water for cooling. Electric generation is at risk during heat waves or severe droughts, as we’ve experienced in recent years. But solar power systems do not require water to generate electricity.
In addition, solar power creates jobs in clean energy. The U.S. has been leading the world in clean energy. Hopefully, this trend will continue, in the face of government budget cuts to the Environmental Protection Agency (EPA) and the United States Department of Energy
(DOE), as innovative and forward-thinking companies continue to embrace the changing landscape of energy production and move to renewables.
(DOE), a medida que las empresas innovadoras y con visión de futuro continúan adoptando el panorama cambiante de la producción de energía y se mueven hacia las energías renovables.
Lastly, there are many Leadership in Energy and Environmental Design (LEED) credits related to solar energy that you can investigate if you are building a green home, such as solar orientation, building orientation for passive solar, and renewable energy. If you are looking to have solar panels installed and save on your monthly energy bills, reach out to Leo Services today. The team of experts will help you achieve your energy goals.