We get a lot of questions
about the price of installing enough photovoltaic (PV) solar panels on a
business or home to fulfill the entirety of one’s electrical needs. Certain
websites are good in regards to the math involved.
Solar Power Authority even hosts
a free quote tool and solar calculator on its site, but they can often be
confusing for the new person. I have put together the following simple rules to
help you put the price into a larger perspective.
One general guideline in the
United States is that normal homes will use electricity at the rate of 1kW/hr
(kWh). Around 730 hours make up each month and the ordinary cost of a kWh of
power comes to $0.10. That means electric bills come to a month-to-month price
of about $73 for a month’s worth of power.
This will obviously
fluctuate a lot when items such as non-standard hot-tubs or certain electrical
appliances are set to run continuously in your home. Prolonged computer use,
video games consoles and plasma screen TVs are also items that have a larger
impact. The amount of electricity your home uses is going to increase
profoundly in months where an air conditioning unit is running as well.
The price of power varies
extensively over the entirety of the United States. Costs can be as little as
$0.07/kWh in West Virginia and as high as $0.24/kWh in places like Hawaii. You
will need to modify my rules to fit your situation as they simply apply to
average homes with normal levels of electricity consumption. A safe number to
apply as a solar panel’s production ability is 10 watts/sq ft.
This indicates that the rate
of panel conversion efficiency is around 12%—which is a good average. This
suggests that for each kW you produce, you’ll want roughly 100 square footage
of solar paneling. If the sun was shining for the entirety of the day, you
would be able to place 100 square footage of paneling and it would be
sufficient to power the typical home.
The sun is usually only
available during the daylight hours and the number of hours you can generate
power in a day depends on the cloud cover as well. The length each day lasts
also depends on the time of year. There are places on the internet to give you
more help when you want to determine the average hours in a day that you can
count on the sunshine.
The normal numbers over the
entirety of the United States will vary from about 3 hours a day in locations
such as Chicago, Seattle and Pittsburgh, to 5-6 hours each day in places such
as California and Colorado.