How to Calculate Your Solar Panel Watt Costs
Solar power is an investment which can reap enormous long term benefits such as slashing electricity prices and helping the environment.
Here are four easy steps to calculate how much solar power you need to halve your current electricity bill.
How much will that power cost to install? Calculate Daily Power Usage: Take your last 12 months of electricity bills and calculate your average kilowatt hour usage per month.
Power consumption varies month by month.
In the summer months, you may use more electricity by power air conditioning than you would in the spring or fall for example.
If you do not have all 12 months, you can either check with your utility, your online statements, or use your last month's bill as a benchmark.
To get your average daily usage, divide by 30, the average number of days per month.
*For example, if your monthly average consumption is 800kWh, then divide 800/30 = 26.
7kWh per day.
If you want to slash your electricity by fifty percent then, you will need to produce 13.
35 kWh per day.
Calculate the total solar panel wattage needs First, determine the amount of usable hours of sunlight your area receive per day.
This is where the solar isolation map comes in handy.
There is a link to it on the website.
Once you determine the daily sunlight hours, take your kilowatt hours needed and divide that by daily sunlight hours.
Multiply that number by a factors of 1.
25 (this takes into account energy losses from solar panel wiring, inverter, and battery) In the example, we have: 13.
4 kWh / 5.
5 hours x 1.
25 = 3.
045kW (3045 Watts per day) *We need our solar panels to produce 3045 Watts per day Calculate the Solar Panel Watt Costs: We will calculate the cost of the solar panels to make 3045 watts in this step.
At the moment the average cost of solar panels in the US is $4.
85 per watt.
This means that it will take 3045 x 4.
85 - $14, 768 to install enough solar panels to halve the electricity bill.
This is before the costs of batteries, wiring, and inverters is calculated.
Offset Tax Credits and Rebates The good news is that there are tons of tax credits and rebates to offset your initial costs.
With the new initiatives happening in California, New Jersey, Connecticut, and Arizona the costs are going to be lowered dramatically.
Lets use the example of a home in California where the state tax rebate is 20% combined with the federal rebate of 40% on the remainder.
There we have: $14,768 - $14,768 x 20% - $14,768 x (1-0.
20) x 40% = $7,089 This is a rough estimate of the costs of solar panels, but it will give you a general idea of how you will use the formula to generate your own cost numbers.
You will need to factor in the costs of hiring an electrician to install the system, storage batteries, and mounting systems.
You can further reduce this initial cost by building your own system.