Solar Energy Systems – Design and Installation Techniques
Solar energy systems utilize the light from the Sun to generate electricity or heat. There are various types of solar energy systems, such as photovoltaic (PV), concentrating solar power (CSP), and solar water heating systems.
Solar systems typically consist of an array of solar panels, an inverter and battery pack. Additionally, it includes wiring, fuses, disconnect switches and voltage meters.
Solar Panels
Solar panels use silicon to generate electricity by absorbing light from the Sun. To maximize output, these cells are placed in series to maximize power production.
Solar modules are rated according to their maximum power point (MPP) when exposed to full sunlight. This reflects how much current the panel can draw and its optimal voltage for maximum output.
Series connections require either a blocking diode within each module string or an external bypass diode to avoid partial array shading. Paralleled connections require placing a bypass diode in series with each module string in order to allow current to bypass shaded modules which would otherwise severely limit it.
It is essential that the electrical run from a solar source to an inverter or charge controller be carefully designed and sized accordingly, in order to prevent tripping fuses or blowing circuit breakers. Furthermore, ensure there is enough headroom for power output from solar circuits arriving at your inverter/charge controller.
Inverters
Inverters convert the power from your solar panels into alternating current electricity that your appliances can use. This conversion involves switches made up of transistors, solid-state devices that work in pairs.
These transistors open and close rapidly, pushing DC electricity back and forth and creating AC current. After filtering, this voltage is then shaped into a sine wave for smooth operation.
Alternating current (AC) is considered the highest quality for home use due to its smooth, undisturbed character and lack of distortion. The utility grid generates AC with generators and then distributes it cleanly and smoothly to customers.
Inverters typically feature several sensing circuits to shut off when they cannot serve the load or supply voltage is too low. This protects your batteries from overdischarge and helps safeguard the inverter itself. Furthermore, some inverters feature isolation functions which prevent transmission of electricity back to the grid during temporary power outages.
Batteries
Battery design and installation are essential elements for a successful solar energy system. Batteries store excess power generated by solar panels so it can be used at a later date.
Energy storage systems can reduce your utility rates and guarantee power in the event of a power outage. Batteries also help avoid peak demand charges and reduce your carbon footprint.
Solar batteries come in two main varieties: lead acid and lithium ion. Both types share similar characteristics such as capacity (measured in kilowatt-hours) and depth of discharge, or how much power can be stored before needing recharge.
Both lead acid and lithium ion batteries require regular upkeep to prevent overcharging or discharge, which could reduce their lifespans. The former is best for commercial applications while lead acid works well for off-grid systems.
Charge Controllers
A charge controller controls the flow of power from a solar panel to a backup battery, helping keep it from overcharging and losing its ability to maintain charge.
Charge controllers come in a range of sizes, costs and capabilities.
Most controllers also feature a display and monitoring feature to keep an eye on your system’s status. This data can help you detect issues early, so that adjustments can be made before they become major issues.
Some chargers feature a heat sensor to monitor your battery temperature and help protect it from overheating.
Furthermore, some chargers can be remotely monitored through a data module connected to the battery’s communication port. This makes it simple to keep an eye on your battery from far away.