A lot of excitement has been developing w.r.t Net Metering policy of Solar Power. Net Metering in simple terms is a policy to convert power users into power producers. Here, the idea is that instead of overall bill that a consumer receives, when he installs solar panels on his/her rooftop, the new bill is net of electricity that he uses of grid and units that his/her solar panels supply to Grid.
A simple illustration:
A commercial consumer, who uses 50 Units of electricity daily, goes for Net Metering based solar power solution. The installed solar panels produce 30 Units of electricity daily. So as per net-metering, his daily billing gets reduced to 50-30 = 20 units only.
Further, lets say, on Saturday & Sunday, the commercial office has holiday and he uses only 5 units on these days instead usual 50. But Solar Power has no holiday and it produces 30 Units daily and so for these two days while the generation is 60 Units , consumption is only 10 units. In such case, the extra units gets credited to the user account and balanced off when he uses next. In our cases, on following Monday and Tuesday while he uses grid electricity @30units/day. He is billed only for 10 units as he/she already has 50 Units in her account.
This balancing is done for each billing cycle and the new bill, NET BILL is actually total units consumed – solar units produced.
In case, units produced are more than consumed, the units remain in account and gets credited to following month.
The electricity rate-unit matrix applied by AVVNL for commercial billing is:
For a commercial consumer whose monthly unit consumption is greater than 500, the rate applied is 7.85+0.4 = 8.25 Rs/Unit. Now, electricity produced by solar panels is in range of 4.0 – 4.5 Rs/unit and is makes good sense for any consumer to substitute these maximum costly(8.25 Rs/unit) to solar energy. The difference in cost of 4.25-3.75 Rs/unit allows for faster payback in range of 4 years.
Another major benefit of Net metering is the system does not use any battery which means a completely static system with zero maintenance cost. Net metering system for first time are actually zero maintenance system. This allows for accuracy in payback period and higher returns for user.
So, the question remains is, what exactly is Net metering system technically?
Well, the answer is simple. Net metering system consists of:
- Solar Panels
- Smart On-grid Inverter
- A meter to check Solar Unit generation
- A net-meter to allow for both direction of current flow and readings.
- A new panel for both solar & grid input and load output.