2kw Solar Panel Systems

Recently, there are many advertisements running on TV comparing prices and sizes of different PV solar systems, and it is time that we investigate just what is happening in terms of the consumers true value received.  One particular commercial is promoting a solar system that is rated at 2 kilowatts or 2kw.  The company, Petersen Dean Solar, talks about their pricing being substantially lower than the competition, by over \$3,000 in costs.  They advertise their solar system as costing only \$6,000 compared to their main competition’s pricing on the same two kilowatt system at \$9,000.  The competitor they mentioned is Solar City which is a larger and more well known solar installer in the United States.

So let’s do some math and find out if a \$6,000 solar system that is rated at 2kw is even worth the investment.  Before we begin, please take note that solar incentives are different throughout the country.  In fine print, Petersen Dean did mention on the TV advertisement that this \$6,000 cost was after incentives.  It is unclear if Solar City’s pricing numbers were before or after the incentives.

The location of the Petersen Dean pricing was for Northern California, so we will use variables for that region of the United States.  You can go ahead and use the sunlight hours page to calculate your specific numbers for your local area too.

Sunlight Hours in Oakland, California:  5.5 sunlight hours per day

Solar Energy efficiency loss: 10% (this is a fair amount to calculate for our equation)

Math Equation: 2 kw * 5.5 = 12.5 kwh / day DC

Conversion to Alternating Current: 12.5 * 90% = 11.25 kwh/day

Monthly electricity from a 2kw solar system: 11.25*30= 338 kwh/month

Average kwh solar savings from the electric company: \$84 per month in electricity savings

Annual Electricity Savings of \$1,014 each year.

So,  it looks like a system sized at 2kw would pay for itself in just about 6 years of service, which is a great investment considering that solar panels are able to last for over 25 years or more.

One thing to remember when calculating your solar panel investment is the cost per kwh from your local utility company.  In the Bay Area of California, PG&E (Pacific Gas and Electric) is the utility company and their rates for electricity are very expensive compared to other parts of the United States.  This greatly affects the investment outlook of solar power.

1. Tom says: