Off-grid solar power systems
Stand-alone solar power systems not connected to the main grid in remote or even in urban areas are known as off-grid solar power systems. In most cases, off-grid solar power systems help to power homes and businesses away from the grid and usually in remote areas. Off-grid solar power systems are widely used in Sub-Saharan Africa, South Asia, and South-East Asia to enable rural electrification efforts of governments or development agencies.
Individuals and businesses interested to harness solar energy from the sun usually buy these systems to generate electricity for their own use. Since grid connection is limited to feed excess power generated by the stand-alone solar system, batteries are connected to store this power for later use. Common batteries used in this context include lead-acid batteries and lithium-ion batteries.
Off-grid solar power systems used in households can be classified into three major categories as captured in a recent World Bank Report analyzing the 2020 Global Off-grid solar market trends in Sub-Saharan Africa, South Asia, and South-East Asia. According to the report, off-grid solar systems can be classified into three categories based on price and end-use application of the solar technology:
1. Pico solar home systems and appliances
Pico solar home systems and appliances have the lowest cost and hence are used in low-income households mainly in Sub-Saharan Africa, South Asia, and South-East Asia. They include small portable solar lanterns, flashlights, or lanterns designed to meet lighting needs. Most of these off-grid solutions are promoted by development agencies and governments in providing energy access to usually rural remote communities that do not have access to the grid. Typically, such an off-grid solar systems solution is embedded with a 0.5 to 10.0-Watt solar panel and an internal rechargeable lithium-ion (Li-ion) battery. In addition, it is connected to an energy-efficient lighting system using LED lights while some models would also include a USB charging port for mobile phones.
2. Solar home systems
Solar home systems include a solar panel with a wattage of 11 Wp and higher and include both home lighting systems and large systems for powering home appliances. There are two types of solar home systems including Plug-and-play and component-based systems solar home systems. Plug -and- play is embedded with a solar panel with up to 100-Watt power rating and a rechargeable battery and may include other energy-efficient appliances such as mobile charging stations, radios refrigerators, etc. On the other hand, component-based systems include individual components such as a solar PV module, battery, lights, inverter assembled by an individual – the individual components may come from different sources or manufacturers. Component-based systems have a power rating of over 11 watts.
3. Solar-powered appliances
Basically, solar-powered appliances include direct current (DC) household appliances ( for example refrigerators) and productive-use appliances such as solar water pumps and agricultural cold storage powered with off-grid solar. Productive use leveraging solar energy includes applications of solar energy in an agricultural, commercial or industrial activity that generates goods or services for the economy. Solar-powered off-grid appliances are designed to be powered using solar energy.
Learn more about off-grid solar systems by vising this web page that explains the end-use applications of solar energy.