What Is a Solar Energy System?
The Sun provides us with a tremendous amount of energy. Solar energy harnesses this power to produce electricity, heat our homes and water, or provide lighting.
A solar power system consists of solar panels, a charge controller (for battery systems) and an inverter. The inverter optimises power output and performs safety functions.
Solar panels are made of semiconductors such as silicon that absorb sunlight and convert it to electricity. Each individual solar cell produces very little power, so they are grouped together into larger units called solar inverter off grid modules or panels. Combined with cabling, brackets, an inverter and other components they form a solar energy system.
The cells inside a solar panel are connected electrically to produce alternating current (AC) electricity. The current generated depends on the amount of sunlight absorbed, the panel’s orientation, tilt and other environmental factors. Solar cells with higher efficiency produce more electricity per unit area. The two most common types of solar panels are crystalline silicon and thin film. Thin film cells involve spraying or depositing materials (amorphous silicon, cadmium telluride) onto glass or metal surfaces in thin layers. This allows them to be made in large panels at a lower cost, but they have lower efficiencies than crystalline silicon panels.
Solar panels are typically installed on roofs and other suitable locations to provide power for a building or structure. They are a semi-permanent feature, and their installation requires that the surrounding roof be able to support them and the weight of the inverter and other components. They also need to be positioned in a way that maximises sunlight capture, which is usually done by having them face south in the Northern Hemisphere or north in the Southern Hemisphere.
Solar battery storage allows your home to utilize its own stored energy at night, or in the case of a grid outage. Basically, the solar panel sends any excess electricity it produces to the battery for safe keeping (similar to how a car battery works). If you don’t have a battery installed, this extra power would flow back to the grid through net metering and you’d get a credit on your next electric bill.
Battery storage capacity is measured in kilowatt-hours (kWh). The rated power of the battery tells you how much energy it can supply at one time and which appliances this can be used to power.
Most residential solar battery systems are lithium-ion based. Lithium batteries have a high cycle life and deep Depth of Discharge, meaning they will last longer and have a better cost per kWh cycle than other battery types.
Most solar battery storage is AC based which means it can be paired with all solar systems that are currently on the market, including microinverters. This makes them very flexible and easy to retrofit into your existing system. They can also provide a backup in the event of a grid failure and help reduce peak demand charges. This can be especially beneficial for homes in areas with frequent outages due to weather or severe storms.
Solar Water Heater
The sun’s rays heat the water in your hot water tank, allowing you to cut out the use of electricity to run your dishwasher, washing machine and to take long outdoor solar lights for yard hot showers. Solar water heating is a cost-effective and sustainable energy solution for your home.
The system comprises a solar collector, insulated piping and a hot water storage tank. Electronic controls can also be included in some systems, along with a freeze protection system for cold climates.
In a direct solar water heater (SWH), the collector is connected directly to the water storage tank. This is known as an open-loop system, and it can be used with a complementary backup heater for times when the sun is not shining.
Other solar water heaters use a heat exchanger to transfer the collected heat into the water. These systems are known as indirect solar water heaters or ICS. They use a tank that is enclosed in a thermally efficient box, which reduces heat loss by convection and radiation.
Regardless of the type of solar water heater used, it is important that the system is properly sized and installed to achieve maximum performance. A professional installer can check the roof’s suitability, look at shading and other factors that might affect efficiency and help you select the right size solar water heater for your home.
Solar Hot Water
Solar hot water systems (SWH) use the sun to heat your household water. They are generally cheaper than conventional water heaters, and the payback period is shorter. They are a good choice for people in areas with high electricity or gas prices.
Most SWHs are passive systems, where an insulated tank stores the heated water for use at night or on cloudy days. Other types of SWH are active, where a pump circulates the heated water directly to faucets and showerheads. These active systems are designed for cold climates, and they use a heat-transfer fluid that absorbs the sun’s energy but doesn’t freeze.
In an integrated collector-storage system, also known as a batch or ICS, the storage tank doubles as the heat collector. The tank is black, which helps it absorb solar energy, and it’s enclosed in a glass-topped box that’s thermally insulated to reduce convection and radiation losses.
Evacuated tube systems, which have rows of transparent tubes that are coated to reflect infrared radiation and a dark absorber at the bottom, offer better performance than flat plate collectors. They can be used in a variety of climates, and they have lower upfront costs than other systems. They also have a longer lifespan than other types of SWHs. They can be more expensive than ICS systems, however, because they require regular maintenance.