Using the equation below, you can estimate the annual electricity production and electric bill savings for a grid-connected home solar electric system with a net metering arrangement.

Determine the PV system's size in kilowatts (kW). A typical range is from 1 to 5 kW. This value is the "kW of PV" input for the equation below.
Based on your geographic location, select the energy production factor from the map below for the "kWh/kW-year" input for the following equation.
Electricity production from the PV system = (kW of PV) × (kWh/kW-year) = kWh/year

You can calculate your annual electric bill savings using the following equation. Note that the residential rate should be in dollars per kWh; for example, a rate of 10 kobo per kWh is input as 0.10 naira/kWh.

Electric bill savings = (kWh/year) × (Residential Rate) = naira/year

(To determine your monthly electric bill savings, divide the final number above by 12.)

For example, a 2-kW system in Ikeja,, at a residential energy rate of 7 kobo/kWh will save about 266 naira per year: 2 kW × 1,900 kWh/kW-year × 0.07 naira/kWh = 266 naira/year (or or 22.17naira/month).Credit- energy.gov
Why bother yourself with all these calculations? That is why we are here. Not only do we help show you how much you will save over an estimated period from adopting solar technology, we also advice you on the type of solution that is best for you after analysing your energy priorities with you. OUR CONSULTANCY FEES? ITS ENTIRELY FREE!!!Yea thats right, TOTALLY FREE. Revolutionalise your home with solar energy solutions, contact us today. Phone no. (Calls between 8.00 am and 6.00 p.m) 09031827710. Email @safeenergyhub@gmail.com.