What Size Solar System Do I Need for My Florida Home?

How to Buy The Right Solar System for Your Home

Collis Roofing PV Solar System Installed in Florida

While paying a high utility bill is a huge pain, trying to figure out how to buy the right solar system can seem daunting. The savings are out there, but trying to understand what size you need, differences in quality, how much it costs, what rebates are out there, what financing is right for you and what savings can you expect can feel overwhelming without professional, expert guidance in the field of solar energy.

Do you need extra insurance for having a large system? Who requires it and how much is it?

The solar experts at Collis Roofing can help you navigate the process, understand your options and have more than just sales experience. The manager of Solar and Energy Efficiency, Denise, has on the ground field experience from installing solar fields, solar topped roofs and more.

What Size Solar System Do I Need?

The size system you need depends entirely on 3 factors - your average monthly energy usage, if you want to go net zero or just reduce your bill and how much roof or yard space do you have that is not blocked by trees or other homes.

Monthly Energy Usage

Your average monthly energy usage is actually found on your utility bill in kWh - kilowatt hours. Locate the total number of monthly kWh your home uses each month. If you need help reading your utility bill you can contact us to help you! These numbers help you understand what size system you need.

Calculating the Energy Production Needed to Match Your Energy Usage

Each panel is 85-92% efficient. No panel is 100% efficient and some panels, including our newest product edition, offers a 25 year warranty not to be less than 85% efficient. We offer two different online 24 hour monitoring systems, Enphase and Solar Edge, that are accessible from any mobile, tablet or computer device with internet access. Each panel is mapped so you can check at any time and see how efficient it is.

One average, a typical Florida day has 5.2 hours of ideal sunlight a day over 30 days. This accounts for days when it may be cloudy as well, but cloudy days do not stop you from gaining solar power, but it is less than an ideal day. Ideal days, are of course, sunny with clear skies.

The more energy you consume or use, the higher your utility bill becomes. That is only because of tiered kWh rates with utility bills. The more you use, the more they charge as you pass certain levels of usage that month per kWh.

How to Calculate the PV Energy Usage in Your Home

Florida Homeowner Paul, after receiving help from Collis Roofing to find his average energy usage on his bills, sees his average energy usage is about 1300 kWh. .

Average monthly energy usage X 85% for non hot water heating power = PV kWh energy usage

1300 X 85% = 1105

Paul then has about 1105 of kWh of energy usage each month that doesn't come from hot water heating

How to Calculate the Size of the PV Solar System You Need

After combining the average hours of sunlight, 30 days in the average month, 85% efficiency in the panels and 15% usage for hot water only, Paul calculates the size system he needs for PV if he wants to eliminate his bill.

5.2 Hours X 30 Days a Month X .85 PV Solar Panel Efficiency = 132.6 Energy Production

1105 kWh Used at Paul's House each Month / 132.6 Energy Production = 8.3 kW System

How to Eliminate the PV Energy Cost at Your House

Whatever the number you get when you calculate your home using the formula below, round your kW size UP to the nearest whole number.

Number of kWh Used / 132.6 Energy Production = kW System Size

To Eliminate the PV Electrical Portion of Paul's home, he needs a 9 kWh system because he is slightly over the 8 kW system size.

How to Reduce the PV Energy Cost at Your Home

Whatever the number you get when you calculate your home using the formula below, round your kW size DOWN to the nearest whole number.

Number of kWh Used / 132.6 Energy Production = kW System Size

To reduce the PVElectrical Portion of Paul's home, he needs a 2.5 to 8 kWh system. a 2.5kW system is typically the smallest PV solar system sold.

How Much Space Do I Need for My PV Solar System?

PV Solar systems require more panels than a Thermal Solar System. Depending on the size system you need, the larger the system the more space needed. A single PV, Photovoltaic, solar panel takes up about 20 Sq Ft. A 2.5k system is 10 panels, and takes up approximately 200 Sq Ft.

If Paul gets a 5 kWh system, he'll need 20 panels and about 400 SqFt. If Paul wants to eliminate his PV portion of his utility bill each month, he'll need 36 PV Solar Panels and 720 Sq Ft of space. This space can be unblocked roof space or ground space if your roof is blocked by trees.

How do I Go Net Zero on My Florida Home?

After installing a PV Solar System that eliminates your PV usage, then you will need a Thermal Solar System for hot water for things such as baths and showers, laundry machines and dishwashers. Thermal Solar systems require significantly less space than a PV system.

Paul has a family of four, so he needs an 80 gallon water tank, a collector which is typically 4x8 or 4x10 and a digital controller. Homeowners with larger families can also opt for a larger water tank upon request.

How Much Will Solar on My House Really Cost?

The price is dependent on the size you need or want. Once we know the size system you need, if you want to reduce or eliminate your power bill, know the local utility company you have, then we can give you a straight forward price and expectation.

Most utility companies only offer thermal rebates, while some like OUC have aggressive rebates for PV for 5 cents a kWh you produce for 5 years! All PV Solar Panel Systems, if installed in 2017 will qualify for a 30% Federal Tax Rebate, which means many homeowners will receive this 30% back as a tax return after filing their taxes.

Systems that exceed 10 kW will need additional insurance per Florida law, but it is often very inexpensive. The reason Florida has this law in place is that Florida basically says you are your own power company. The Collis Roofing Solar and Energy Efficiency Manager can help you coordinate setting this up.

Collis Roofing also offers a variety of financing options from 12 months same as cash to 5.99% for 20 years from lenders who specialize in solar loans in Florida. Available financing options are subject to change at any time. Talk to your estimator for more information or our financing specialist.

The average PV solar system will pay for itself in just 8 years.