The Basics of a Solar Energy System

Solar energy is a clean and renewable source of electricity. It can also be used to heat water or operate appliances and machines.

It’s no secret that solar energy is a great way to lower your electricity bills and reduce environmental impact. But how exactly does it work? This article will explore the basics of solar energy systems.

Solar Cells

The heart of any solar energy system is the solar cell, a semiconductor that converts sunlight into electrical current. The vast majority of solar cells are made from silicon, though researchers have also developed amorphous, organic polymer, and perovskite crystal solar cell types.

Solar cells work by absorbing the sun’s energy and “knocking” electrons loose in their top layer of negative-charged silicon. These electrons are then naturally attracted to the positively charged bottom layer of the cell, creating an electric current that flows through metal contacts at the top and bottom of the solar cell. This current powers devices as small as a calculator and as large as power stations.

While the physics is fairly simple, solar cells are still improving in efficiency and cost. The first solar cells scraped by with a mere 6 percent efficiency, while cutting-edge lab types can achieve up to 47 percent in perfect conditions.

To maximize their efficiency, solar cells are grouped together into modules and arrays. The SOLAR INVERTER modules are then confined in an ultra-durable plastic material like silicone rubber or ethylene vinyl acetate and covered with a glass sheet for protection. A metal frame latches onto mounting clamps that secure the array to your roof. In addition to ensuring that your solar panels are well-protected from the elements, this encapsulation ensures that electrical contacts don’t interfere with each other or block sunlight.

Solar Arrays

A solar array is the collection of panels that work together to generate electricity. Each panel has silicon solar cells that convert sunlight into direct current (DC) electricity. This DC electricity is sent to a solar inverter system, where it’s changed into alternating current (AC) energy that can power your home. When you generate more electricity than you need, the excess can be fed into the grid.

Depending on your home’s electricity usage, you may need more or less panels to generate enough energy. A good place to start is by looking at your electricity bills from the past year and multiplying your average daily consumption by 1,000 to get the number of watts you need.

Rooftop solar arrays are the most common, but solar panels can also be mounted on ground-mounted structures like carports or gazebos. In addition, some people have a solar-powered RV or boat.

Whether you’re installing a rooftop or ground-level array, look for high-quality equipment from an experienced installer. You want to maximize your solar energy production and avoid any unnecessary costs.

Photovoltaic (PV) Panels

Photovoltaic cells convert sunlight into usable electricity. They are made of semiconductor material that has been layered and bonded together to create an electric field across the cell. Only photons with energy above the band gap of the semiconductor can free electrons to run through an electric circuit that produces power.

The cells are connected together to form panels that produce current, voltage and wattage. Usually, metal contacts on the top and bottom of the panel allow current to flow out of the cell. When matched with an external circuit, this can be used to power household appliances or to charge batteries.

PV solar systems may be categorized by the way they are designed to interact with the grid, which can determine their efficiency and cost effectiveness. For example, the system design must ensure that the solar array is not shaded (which reduces performance by two-thirds) and it should be mounted at an optimum angle of inclination for the local latitude.

Large-scale PV plants, called solar parks or solar farms are usually combined with other renewable sources to supply electricity for local consumption (grid-connected plant) or sold into the grid. They can also be connected to a battery and provide back-up power for the grid. They are often built in remote locations and must use transmission lines to bring electricity to cities, which causes line losses as the power travels long distances.

Solar Power Towers

A solar power tower is a solar energy plant with the ability to produce more electricity in less time, day and night outdoor pathway solar lights than traditional flat panel solar arrays. They also can generate more power in locations that don’t have a lot of sun, on cloudy days or during winter.

A large field of flat, sun-tracking mirrors (known as heliostats) concentrate the sunlight on a receiver located at the top of a tall tower. The heat from the concentrated rays is used to heat a working fluid which turns water into steam to turn a turbine generator. In its first iteration, the working fluid was water but more advanced models use molten salts like sodium nitrate because they have a higher heat storage capacity and operate at a lower pressure than water.

The tower’s structure allows for better energy generation than traditional solar panels because it can be made to track the sun across its entire arc over the course of the day, unlike the rotating mirrors found in photovoltaic systems that only cover a small area of the sky. The curved reflectors and receiver also allow for better performance during cloudy or snowy weather.

Currently there are several commercial solar tower plants operating in the US Southwest, Chile, southern Spain and India. However, some projects like Cerra Domidor in Chile were shut down due to funding issues and others have been canceled.