What appliance is used 365 days a year in your home? Your home’s air conditioner or refrigerator? You could say the air conditioner does not get used every day, as there are some cooler days when your air conditioner is turned “Off”. So which appliance gets used every day of the year, no matter the weather outside? The answer is your water heater. According to FPL, LCEC and the Florida Solar Energy Center, your water heater is the second largest annual electric consumer in most Florida homes. Second only to the air conditioner. So what can you do as a homeowner to save on water heating costs?
There are two main options when deciding to make your home’s water heating methods more energy efficient: Solar Water Heating or a Waste Heat Recovery Unit.
Solar Water Heating
A solar water heating system will handle about 90% of your home’s annual water heating needs. The system is composed of a solar water heating panel about the size of a plywood sheet. This solar panel circulates the water, heating it with the heat from the sun. The solar water heating system also includes an 80 gallon water heater tank to store heated water for use of up to 2 days. The solar water heating 
system also includes a circulating pump, which is completely operated by a mini-solar PV panel. This small solar electric panel makes the pump independent of you home’s electricity. With this small panel, the solar water heating system will operate even if there is a long power outage. For a Solar Water Heating system to perform at it’s highest efficiency, a Southern exposure is the key.
Rebates & Tax Credits for Solar Water Heating Systems
FPL is offering $1,000 to homeowners who install a new solar water heating system. The FPL Solar Rebates are only offered for a limited time but can be combined with other incentives. The Federal Government provides a 30% tax credit on the total cost of a solar water heating system. With these two incentives, from FPL and the Federal Government, it is easy to go solar, go green and start saving 90% on your water heating costs!
Waste Heat Recovery Unit
A waste heat recovery unit will handle about 70% of your annual water heating needs for your home. The system is a “box,” about the size of a shoebox, mounted outside by your air conditioner. It is not a water heater itself, but a measure to heat the water inside your existing tank. The waste heat recovery unit eliminates the need for your water heater tank to use the electric heat resistance. This is done by the waste heat recovery unit when your air conditioning system is running. The “wasted heat” that is dissipated and released into the air by the outdoor unit is transferred through the heat exchanger into the water in your existing water heater tank. However, for the system to work effectively, the air conditioner must be continually running. On average, 5 gallons of hot water is produced for every ton of air, per hour. For example, a 3 ton air conditioning system will produce about 15 gallons of hot water per hour of run time. Also, Waste Heat Recovery systems start to lose efficiency when tied to an air conditioning system rated 17 SEER or higher. As the newer, more efficient air conditioning systems run less to remove the heat from your home, the heat received from the air conditioning system decreases. If you are considering replacing your air conditioning soon with an ultra high efficiency system, you would be better off with a Solar Water Heating system. Currently, there are no tax credits or rebates offered for adding a waste heat recovery unit to your home’s air conditioning system.
The goal of the FL Green Team is to provide members of the Southwest Florida community with information to make their home more energy efficiency, comfortable and healthy through education, energy upgrades and innovative testing.