Grid tied systems consist of only 2 key components – solar panels and a dedicated grid tied inverter. All the electric power generated by the solar panels feeds through a mains synchronized inverter directly into your distribution board and offsets the power you would normally consume from Eskom. It will of course only do this when the sun shines! If the panels produce more power than what is being consumed at the time, the balance will flow back into the network and it will actually reverse the electricity meter (not all types of meters can do this though). Since no batteries are used, no independent energy can be stored for later use. This means that energy required at night will still be obtained from the network.
Components of a Grid Tied system
1. Solar Panels
2. DC-AC grid-tied solar inverter
3. Solar cables
4. Mounts
Main benefits of Grid Tied Solar PV Systems:
• Energy provided by the Sun – saving money.
• No expensive batteries required.
• Sunlight is directly converted into electricity to use.
• At current electricity costs, system payback is between 4 to 6 years.
• Cost of energy yield fixed for at least 25 years.
• The only home improvement that will save you money on a daily basis!
• No maintenance required.
Main disadvantages of Grid Tied Solar PV Systems include:
With no batteries, there is no independent energy storage.
During load shedding or a power outage, the system switched off also.
Current legal issues in South Africa can limit the full benefits in certain applications like being paid for power supplied to the grid by the utility.