Understanding Types of Solar Energy Systems

A Solar Power System is used to convert solar radiation directly into electricity. The heart of this system (also known as PV (photovoltaic) system) comprises of solar cells which are organized to form solar arrays and modules i.e. solar panels.

The size of the system may depend upon the task it’s going to be used for. A complete solar power system is made up of components like a DC-AC inverter, an auxiliary energy source and a battery tank. In addition to these it also includes a variety of balance of system (BOS) hardware, wiring, overcurrent, surge protection, and other power processing equipment.

The two main types of solar power systems are:

Stand Alone Solar Power Systems – These systems operate independent of the utility grid and their purpose is to supply DC or AC electrical loads. Powered either by a solar array and sometimes wind, an engine generator or general power supply they are also referred to as solar hybrid systems.

The simplest stand-alone system is called a direct – coupled system. In this system the DC load is directly connected to a solar array. Owing to lack of batteries in a direct – coupled system, load only functions in the presence of solar radiations and not otherwise. This makes this system perfect for regular applications like water pumping, circulation pumps, solar water heating, and ventilation fans etc. Nevertheless, the use of batteries is common in many types of solar hybrid systems.

Grid Connected Solar Power Systems – These systems are made to work simultaneously with the power utility grid and are interconnected with it. The inverter or the PCU (Power Conditioning Unit) converts DC into AC power and is enough to the power most requirements of the utility grid. This system is appropriate for homeowners and small businesses where power is required for critical loads such as water pumps, lighting and refrigeration.

Based on the classifications above there are some particular kinds of Solar Power Systems in use today:

Solar Trough Systems – This system is commonly used in commercial solar power plants to convert heat into electricity. Sharp concave reflectors concentrate sunlight to around 60 times its normal intensity on to a pipe passing at the focal line of the trough. The oil circulating through this pipe heats up to around 390 degree Celsius. It is then passed through a heat exchanger in a generating station to produce steam, which produces electricity using the steam turbine.

Solar Power Towers – Fit for producing electricity on a large scale, this one of a kind technology can store energy efficiently. They can operate under all circumstances i.e. during nighttime or cloudy weather. Sunlight is reflected from thousands of mirrors and is then focused onto a receiver, which is centrally located at a considerable height. Similar to the Solar Trough System, the heat is collected in a heat exchanging fluid and is pumped through a heat exchanger to produce steam to power a conventional steam turbine.

Solar Dish Systems – This system is made of a mirror grid arranged in shape of a dish and helps to focus sunlight onto a receiver which transfers energy to a special engine that in turn creates electricity. It is the most advanced solar power technology today with a conversion efficiency of around 30%. This is the highest among all solar power systems.

Solar Power systems are becoming more popular, both on a commercial and a domestic level. They are easy to install, easy on the pocket and easy on the environment.