The harnessing of solar energy is basically the collection of radiant light and heat from the sun. The radiant light and heat that is harnessed is put to use using different technologies and is in the end stored for future use. The only way this energy can be stored is through the use of thermal mass systems. These systems store energy in the form of heat for seasonal or daily durations.
Thermal storage takes the form of materials with a high specific heat capacity. Some materials such as Glauber’s salt and paraffin wax are relatively cheap and available are known to offer domestically useful temperatures of about 64⁰C. When at high temperature, molten salts can be used in the storage of solar energy. The advantages of salts is their ability to deliver heat at temperatures that are attuned to conventional heating systems. These salts have a high specific heat capacity and are relatively cheap.
The orthodox way of storing excessive electricity from the solar system is the use of batteries. These are the off-grid Photovoltaic Systems.
Fig1: the use of batteries in storage of solar energy
With the PV solar power system, the solar energy is stored in two ways.
- Grid Inter-Tie
- Battery Banks
With the battery bank, the energy generated by the PV system is stored in a series of batteries. The batteries are also present in the off-grid PV system and the grid-tied PV system. As shown in figure 1, the major parts of the battery solar power system include;
- Battery Bank: an array of batteries that are adequately wired. Theses batteries are very alike to the normal car batteries, but are specifically engineered to withstand the constant charging and discharging.
- System Meter: this is the normal ac meter system that displays the status and performance of the solar PV system.
- Charge controller: there might be risk of overcharging. This component interrupts electric flow when the batteries are full.
- Main DC Disconnect: there is need for the inverter to be disconnected from the battery bank. The main DC disconnect achieves this by using a DC rated breaker between the battery bank and the inverter.
- Top of Form
- Bottom of Form
Works Cited
Balfour, J. R., Shaw, M., & Nash, N. B. (2013). Introduction to Photvoltaic System Design. Burlington: Jones & Bartlett Learning.
Balfour, J., Shaw, M., & Nash, N. B. (2012). Advanced Photovoltaic System Design. Burlington: Jones & Barnett Learning.
Dunlop, J. P. (2010). Photovoltaic Systems. Orlando Park: American Technical Publishers.
Sukhatme, S. P., & Nayak, J. K. (2008). Solar Energy: Peinciples of Thermal Collection and Storage. New Delhi: Tata McGraw-Hill.
