Types of Solar Energy Systems

Solar energy is radiation from the Sun that can be used to make electricity or heat. It is a renewable resource, unlike coal and oil.

Solar energy systems use a range of technologies to capture sunlight. The most common are photovoltaics and concentrated solar power.

Photovoltaic (PV)

Photovoltaic systems generate electricity directly from sunlight. This is a non-polluting, clean energy source that can be used to power your home. There are a range of solar PV system sizes to suit your needs. They are also able to connect to the electric grid and be fed back into the power system.

A solar PV cell converts the sun’s energy into direct current (DC) electricity. The amount of electricity it produces is proportional to the intensity and duration of the solar-energy-systems sunlight. The cell’s output voltage is also dependent on its temperature, with each 25 degrees Celsius increase in the cells temperature reducing its output power by 5%.

The cells are grouped into panels to produce more electricity at a greater output capacity. Each panel is a group of cells that are connected in series and encapsulated into an environmentally friendly casing. The power produced by a solar PV module is equal to the sum of the DC current of each individual cell in the panel, divided by its voltage.

While PV solar panels produce a significant amount of energy, the battery bank ensures service continuity. This can be useful for keeping lights on, running appliances or during periods of low sunshine. It can also help offset the cost of your investment, by exporting excess electricity to the power grid and receiving tariffs in return.

Concentrating solar power (CSP)

Solar power plants rely on mirrors to concentrate sunlight and harness it as thermal energy, which can then be used to produce electricity. These systems use parabolic troughs, central receiver, power tower or dish/engine technologies to heat up a working fluid, such as water or steam, which is then used to run a conventional turbine/generator to produce electricity.

Concentrated solar power is a type of solar energy that has been around for centuries, with Archimedes reportedly using a series of bronze shields to concentrate sunlight on invading Roman ships to burn them. The earliest commercial CSP installations were in the 1840s, when August Mouchout used parabolic trough systems to heat and make steam to drive a turbine generator to produce electricity.

A key advantage of CSP over other renewables is the ability to store thermal energy for use at times when sunlight is not available, such as at night or on cloudy days. However, despite this advantage, CSP plants have been largely abandoned as other renewables have made more rapid progress toward being viable sources of power.

The concentrating solar power technology is often located in arid regions (known as the Sun Belt), where access to large amounts of fresh water is important, both for cooling the working fluid and cleaning mirrors. Additionally, the focusing system required by these systems limits production potential in areas with less than ideal solar radiation (measured as direct normal irradiance). All large concentrating plants constructed since 2013 include thermal energy storage.

Passive systems

Passive solar design techniques take advantage of natural energy characteristics of materials and air to regulate the temperature in living spaces without mechanical systems. These designs are cost-effective and easy to implement. They can reduce energy bills, help to eliminate dependence on power companies and make buildings more sustainable.

In a passive solar heating system, sunlight enters a building through windows and strikes thermal mass incorporated into Energy storage brick floors and walls. This stores the solar heat until it’s needed during the day. Sun-tempering also uses a variety of other architectural techniques, such as increasing the number of windows on the south side of the house or adding overhangs to shade the windows during the winter.

Passive cooling systems also use architecture, shading, and ventilation to reduce the build-up of excess heat during the day. This reduces the need for electric cooling, and allows cool night air to be stored in the house.

When locating a site for a new building, it’s important to consider solar access. The land should slope gently to the south and be free of tall trees or future development that could block the sun’s path in summer. If possible, zoning and other regulations should protect solar access.

Active systems

Unlike passive systems, active solar energy systems are designed to control their impact on the environment. They are also often integrated into the building cladding components and can include trackers. They use low voltage direct current (DC) blowers or pumps to power the collectors. The controllers optimize the speed of the device depending on the available solar heat gain and energy requirements. They also monitor the temperature in different parts of the system and adjust accordingly.

These technologies generate heat or electricity for space heating, hot water, and/or air conditioning. They can be combined with storage to improve efficiency and reduce the cost of operating a system. They are used in buildings of all sizes and types. Some systems can provide all of a building’s energy needs, while others can be used for specific applications such as domestic hot water or space heating.

They can also be combined with other renewable energy technologies to create hybrid or distributed energy systems that meet a building’s energy needs with more reliability than the grid can supply. They can be designed to work with micro-grids and national energy networks, using smart controls to manage demand side response and load shifting.

Depending on the type of system you choose, you may need to have it installed by a licensed contractor. Check with your local government or utility company to learn more about licensing requirements.