Solar Water Heating Basics Progress Energy Florida Solar Water Heater Incentive Program Colleen Kettles Florida Solar Energy Research & Education Foundation (FlaSEREF)

Solar Water Heating Basics How It Works How Much Energy It Saves How It Helps the Environment How To Purchase How Much It Costs What Incentives Are Available

Types of Systems “Active” System Direct Pumped Indirect Pumped Water is the collector fluid Freeze protection provided by drain-back tank or freeze valves Indirect Pumped Anti-freeze is the collector fluid Heat exchanger utilized within storage tank

Active Solar Water Heater

Active Solar Water Heater Direct Pumped Water in the collector is heated by the sun. The differential controller

Active Solar Water Heater Direct PV Pumped

Active Solar Water Heater Indirect Pumped

The Collector Active Systems Use “flat-plate” collector Insulated box with ½” copper piping integrated into a black absorber and glass cover Fluid is water or anti-freeze Designed to reach temperatures as high as 160° F

The Storage Tank Active System Specially designed, heavily insulated tank (R value of 16 or greater) Sizes range from 52 to 120 gallons for residential applications Has only a top electric element In a system using antifreeze, the tank will have an internal heat exchanger

Balance of System Components Active System Pump (ac or dc) Differential Controller, or Photovoltaic Panel Assorted valves and vents Copper Piping Insulation

Types of Systems “Passive” System Integral Collector Storage Collector provides additional water storage No moving parts

Passive Solar Water Heater Integral Collector Storage

Passive Solar Water Heater Integral Collector Storage

The Collector Integral Collector Storage (ICS) The collector is also the storage medium Insulated box with 4” copper tubing welded together to serve as the absorber Glass cover Fluid is water Designed to reach temperatures as high as 160° F

The Storage Tank Integral Collector Storage (ICS) Collector provides ½ of the storage (32-50 gallons) Existing or conventional tank provides the balance of storage

Balance of System Components ICS System Assorted valves and vents Anti-scald valve (optional) Copper piping Insulation

Types of Systems “Passive System” Thermosiphon Tank is roof mounted above collector Uses flat plate collector No moving parts Reminiscent of early solar systems

Early Thermosiphon Solar Water Heater

Thermosiphon System

Passive Solar Water Heater Thermosiphon System

The Collector Thermosiphon System Uses “flat-plate” collector Insulated box with ½” copper piping integrated into a black absorber and glass cover Fluid is water or anti-freeze Designed to reach temperatures as high as 160° F

The Storage Tank Thermosiphon System The storage tank is specially designed to be mounted on the roof above the collector An auxiliary tank with electric element is installed in the home

Balance of System Components Thermosiphon System Assorted vents and valves Copper piping Insulation

Household Hot Water Use 15% – 20% of total household energy consumption Daily usage is 20 gallons each per day for the first two occupants; 15 gallons per day for each additional occupant Example: Four person household will use 70 gallons of hot water and will need 80 gallons of storage

Collector BTU Ratings /Solar Fraction Central Florida ambient water temperature is 72 degrees Solar fraction is the proportion of hot water provided by the solar system Optimal solar fraction is 70% and is based upon annual performance

Collector Btu Ratings /Solar Fraction 38,000 Btus will be needed to raise 80 gallons of cold water to 122 degrees A 32 square foot ICS system is rated at 28,700 Btu/day and will provide a 77% solar fraction A 40 square foot active collector is rated at 34,400 Btu/day and will provide a 92% solar fraction

Savings The kWh equivalent of 38,000 Btu/day is 11.13 kWh per day x 365 days = 4,063 kWh/year (electric load) A solar fraction of 70 will offset 2,844 kWh A solar fraction of 77 (28,700 Btu/day) = 8.4 kWh/day x 365 days, saves (or produces) 3,066 kWh/year A solar fraction of 92 (34,400 Btu/day) = 10 kWh/day x 365 days, saves (or produces) 3,650 kWh/year

Savings At an average residential rate of $.115 per kWh: A solar fraction of 70 will save $325/year A solar fraction of 77 will save $350/year A solar fraction of 92 will save $420/year

Back-up Hot Water All solar water heaters will have a conventional energy back-up No consumer action is required to activate the back-up Back-up is needed for periods of excessive hot water use or inadequate solar resource

How It Helps the Environment Emission Reductions (One Solar Water Heater Saves Annually) Carbon Dioxide (5,000 lb) Sulfur Dioxide (20 lb) Nitrogen Oxide (12 lb) Renewable Energy Credits The “environmental attributes” of solar energy are a commodity

How to Purchase Contact reputable solar companies www.flaseia.org www.findsolar.com Verify contractor licenses www.myfloridalicense.com Voice: 850-487-1395 Solar contractor (CV) Specialty solar (CW) Plumbing contractor (CF) Local solar license (RX)

How to Purchase Get more than one estimate, and get them in writing Avoid high pressure sales tactics Compare system types, sizes, prices and warranties Ask for FSEC system certification Ask for local references

How to Purchase A local building permit should be obtained prior to installation (although some jurisdictions no longer require) Contractor, not the homeowner, is responsible for the permit If in doubt, homeowner should contact the local building department Deed restricted communities will typically require prior approval (which cannot be denied)

How Much It Costs Cost of a system varies depending upon the type of system and the size of system Prices range from $3,000 to $5,000 in general Rising material costs and the cost of doing business (gasoline, insurance, etc.) have resulted in price increases

Financial Incentives Incentives are designed to lower the cost to the consumer Sales Tax Exemption (6-7%) Florida Solar Rebate ($500) Progress Energy Rebate ($450) Federal Tax Credit (30% with cap of $2,000)

Interaction of Incentives Rebates should be deducted from the cost of the system before the federal tax credit is calculated IRS has not issued regulations under this tax credit law Exception would be if rebates are included as gross income

Interaction of Incentives Example – System cost: $4,000 State rebate: - $500 PEF rebate: - $450 Actual cost: $3,050 Federal tax credit: (.30 x 3,050) = $915 Net system cost: $2,135

Impact of Incentives on Consumer Savings Net System Price of $2,135 Annual Savings of $325 = 6.5 year payback Annual Savings of $350 = 6.1 year payback Annual Savings of $420 = 5 year payback

For More Information THANK YOU www.flaseref.org www.flaseia.org www.fsec.ucf.edu www.floridaenergy.org 800-59SOLAR THANK YOU