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(FREE Diagram) Solar Attic Fan With Battery Backup

When switching to off-grid living, you should first think of reducing your energy consumption. Your home needs to be very energy-efficient, and roof insulation may not be the best option for you. 

Think of hot summer days where you try all means to keep your house cool? You might find it very expensive to run your HVAC system because of the high cost of electrical energy. A solar attic fan with battery backup is the best solution in such situations.

What Is an Attic Fan, And How Does It Work? 

Solar Attic Fan with Battery Backup
Can You Build Solar Attic Fan System with Battery Backup?

An Attic fan, also known as an attic ventilator, is a standalone system installed on the roof to help regulate the air conditioner in your attic. It consists of a solar-powered fan and sometimes a battery backup. 

During the day, the system runs entirely on solar power from the sun, and excess electric power generated is stored in the backup batteries. At night, when there is no sun, the attic fan automatically switches to battery power to keep your attic under optimum condition.

Attic fan ventilation removes hot and stale air from the attic space and brings in fresh and cooler air from outside. This process helps in cooling your home during summer. 

Also, the attic fan system can regulate attic humidity. This means you need soffit vents installed in the eaves for air circulation.

Why Do You Need A Solar Attic Fan with Battery Backup? 

Why Do You Need A Solar Attic Fan with Battery Backup?
Solar Attic Fan with Battery Backup Helps cooling during night and summertime.

If your AC system does not work well in keeping your home cool during the summer seasons, then it is high time you look for better alternatives. 

As mentioned, running an HVAC system 24/7 can be expensive for an off-grid lifestyle. Under such conditions, an attic fan proves to be the best alternative to give you the comfort you deserve at home. But why a solar attic fan and a battery backup system?

Saves overall energy consumption 

An attic fan helps you save on energy because it runs purely on free solar power. The solar panels are used to charge the lithium-ion battery, which provides power at night.

That means your attic fan ventilator does not require additional power, allowing you to achieve off-grid living.

When the attic fan runs, it cools your home. That means your AC system has less workload. It will even last longer without servicing and/or replacement, thereby reducing the total cost of managing excess heat in your house.

Increase the life of your roof 

If you ever climbed to the attic space during summer, you understand the heat and humidity there is. These are the exact conditions that promote mold growth, which destroy roof shingles and other materials. 

You need proper ventilation to make your roof serve you better and longer. Installing a solar attic fan with battery backup gives you a lasting solution to this problem as both humidity and temperature are controlled.

The roof material can absorb moisture during cold winter months that encourages mold and mildew growth. Also, vapor from daily routines can condense at the attic space when they meet cold roof materials. The condensed vapor can damage attic insulation materials. 

A warm attic during winter also promotes ice damming. Installing solar attic fans is the most cost-effective way of putting an end to all these problems and improving the lifespan of your roof.

Emergency AC backup 

Your AC system can break down at any time due to wear and tear. When that happens, your off-grid home will become practically uninhabitable in the summer. A solar attic fan is the best backup system to keep life going while repairing the HVAC or finding a replacement.

Improve home comfort for less 

An attic fan ventilation system can lower the attic temperature by up to 40 oF. This will keep the temperature of all rooms below the attic inhabitable even during the summer. Like all other attic fans, solar attic fans are also crucial in controlling condensation in the winter.

Significantly save energy and roof repair costs when installing a solar attic fan. Once purchased, you no longer have to worry about monthly utility bills. Your off-grid life is assured, and the good news is that attic fans last longer. 

The cost of frequent roof repair is also immense. You can save all that if you choose to install solar attic fans.

No noise pollution 

No one likes staying in a room with noisy fans, especially at night. Many of the solar attic fans in the market today are made of brushless motors.

40-Watt Solar Attic Fan (BDB)

Remington Solar 40 Watt/ 38V Roof Mount Solar Attic Fan with 110V Smart Adapter
  • POWERED BY FREE SOLAR ENERGY… FIGHTS MOISTURE DAMAGE: Finding Moisture Damage in your home can cause severe consequences to your home’s value and your family’s health. This solar exhaust fan is fueled by the Sun & Automatically Combats Moisture!
  • POWERED BY FREE SOLAR ENERGY… FIGHTS MOISTURE DAMAGE: Finding Moisture Damage in your home can cause severe consequences to your home’s value and your family’s health. This solar exhaust fan is fueled by the Sun & Automatically Combats Moisture!
  • INCLUDES HYBRID ADAPTER TO AUTOMATICALLY RUN AT NIGHT… HUMIDISTAT & THERMOSTAT BUILT-IN: Heat & Moisture damage your attic & can create HUGE repair bills… Remington Solar’s roof fan includes an Adapter to Run at Night, as well as a Humidistat & Thermostat to automatically change airflow based on your attic’s needs!

That makes them very quiet, giving you the peace of mind you need to enjoy your night. You can breathe easily without the worry of disturbing noise from conventional electric fans.

How Do You Build A Solar Attic Fan with Battery Backup?

How Do You Build A Solar Attic Fan with Battery Backup?
How Do You Build A Solar Attic Fan with Battery Backup?

A solar attic fan is ready for use right from the box. A set usually comes with a high-impact solar panel, fan, and thermostat for regulating temperature. If yours does not have one, you need to buy one separately and wire it to the system.

To build a solar attic fan with battery backup, you need the following:

  • Solar fan
  • The solar panel (30 or 40 watts)
  • Thermostat
  • 12 volts lithium-ion battery
  • Solar charge controller.

Here, the solar charge controller protects the battery from overcharging or over-draining, helping to extend the battery’s life.

Wiring diagram

You need to wire your system correctly to make it functional. An attic solar fan with a battery backup is not an overly complicated system. Connect the components as shown in the diagram below and set an optimal temperature using the thermostat.

Solar Attic Fan with Battery Backup Wiring Diagram
Solar Attic Fan with Battery Backup Wiring Diagram

For safety, you might need to install appropriate circuit breakers. But this low-voltage should be safe enough if you make all the connections as shown in the diagram. Consult with your technician if you are not sure.

Final Thoughts on Solar Attic Fans 

A solar attic fan is the best option for people who desire off-grid living. They also help you reduce your environmental carbon footprint as they only use free energy from the sun.

Since attic fans also have a backup battery, you can leave them running for 24 hours every day of the week without the fear of high electricity bills. Total comfort and peace of mind are all you pay for when buying and installing solar attic fans.

Amtrak Solar Powerful 50-Watt Galvanized Steel New Upgraded 14″ Fan Housing, Solar Attic Fan Quietly Cools, Ventilates Exhaust Your House, Garage or RV

Amtrak Solar Powerful 50-Watt Galvanized Steel New Upgraded 12" Fan Housing, Solar Attic Fan Quietly Cools, Ventilates Exhaust your house, garage or RV and protects against moisture build-up
  • ( High efficiency fan blade ) New 12” Fan Housing with 10” High Efficiency fan blade. Enough to open louver. Easy to install with quick-connect wires. Reversible push and pull fan.
  • ( Numerous Applications ) For gable vent, greenhouse, garage, shed, cabin or RV. Includes 15’ of extra wire and brackets.
  • ( High Torque Motor ) Features sealed ball bearing and Thermal protected fan motor with fully balanced high efficiency fan blades for low noise level and long life. Covers areas up to 2250 Sq. Ft.