While most people know the cost and environmental benefits of solar power, few know how they actually work. The magic behind this sun-to-energy conversion is much more straightforward than one might think.
How Do Solar Panels Work?
To really understand the science behind solar panels it is necessary to break down the two different types:
1. Photovoltaic panels that produce electricity
2. Solar thermal panels that are used for heating purposes
Solar Photovoltaic Panels
Photovoltaic systems are composed of a number of cells, which are made of semiconductors, such as silicon, which absorb direct sunlight generating direct current (DC) energy. Inverter technology then converts DC energy into useable alternating current (AC) energy, which then flows through a home’s electrical panel and is distributed appropriately.
The layer of silicon cells is held together in a metal frame, within a glass casing, with various wires to allow a current to flow from the cells. Since silicon is a non-metal but contains conductive properties, it can absorb and convert sunlight into electricity. Known as the ‘photovoltaic effect’, the flow of the electrical current is a result of the sun setting the electrons within the cell in motion.
The light-absorbing solar cells are connected through an electrical circuit within a frame, commonly known as a solar panel, and multiple solar panels connected together are known as a solar array. When cabling, brackets and invertors are all added. The array of panels is then known as a solar system.
Using Solar Photovoltaic Panels at Home
The typical home uses 4kW of electricity, which would require about 16 solar panels with a 250W power output. However, this is not a hard and fast rule. For those looking to invest in their own solar system, a few considerations need to be made to determine the number of panels required.
1. What is the current level of electrical consumption?
2. What is the roof capacity?
3. How many hours does the sunshine in the local area?
Once the optimal number of panels has been decided upon, attention then needs to turn on the best position to maximize efficiency. Factors that impact efficiency include the angle, location, direction, and roof suitability.
Solar Thermal Collectors
Rather than using sunlight to produce electricity, solar thermal panels heat up water that is stored in a connecting cylinder, which is then transferred into a home or business in the form of hot water or space heating. Solar collectors use the sun rays to heat a liquid solution, which is usually a mixture of water and glycol to prevent freezing in winter. This heated liquid is then pumped into a heat exchanger within the water cylinder, which in turn, heats all the water contained in the cylinder. Once all the heat contained in the liquid has been released, it will then be recirculated back to the collector to begin the process again.
Choosing the Right Solar Thermal Collectors for a Home
When investing in a solar thermal collector, it is the size of the cylinder that is most important. A 200-liter tank is connected to one panel and should suit households of 1 to 3 people, an ideal option for properties with limited ground space. A 300-liter tank, which is connected to a double panel, is perfect for homes of 3 to 5 people where hot water is in high demand.
For occupants of the home with more limited space or more specific roofing needs, Eurosun solar hot water comes with a range of options. Roof solar systems work well in urban areas as they help to make the most out of ground space, whereas split solar systems are best for homes with less roof space since the panel is attached to the roof and the cylinder is on the ground, either inside or outside the house.
Heat pump systems are available when attaching a panel to the roof is not an option. These work by utilizing the ambient warmth of the surrounding air, rather than the rays of the sun.
What are Some of the Advantages of Solar Power?
• They require less space than other forms of renewable technologies and can be installed in a wide variety of locations
• The unobtrusive presence makes them the best option in terms of biodiversity
• Once installed, they require little to no upkeep — only a little cleaning to keep them free of debris
• Solar panels are safe and nontoxic
• They do not produce noise pollution and therefore can be used both in the countryside and densely populated urban areas
