Off-the-Grid Solar Wagon

The Solar Wagon can be used as a portable or emergency energy system to charge laptops, cell phones, LED lights, or computer speakers. It is made from a re-purposed garden cart with a custom-built solar panel frame and off-the-grid solar electronics shelf. The project budget ranges from $500-$1500 depending on the materials, tools and solar components that you buy or might already have. If you have not welded or worked on solar electronics before, take a class or collaborate on this project for best results.

For more info on our Solar Charging Station projects and workshops see:
www.SolDesignLab.com
www.facebook.com/soldesignlab
info@soldesignlab.com

Collect all the tools and materials needed for this project.

Build a frame on top of a sturdy steel garden cart to hold the solar panel and electronics (bolt or weld together).

Extra: waterproof the electronics box, make the wagon lockable, add graphics, add a bike hitch.

Material Supply Options

• www.altestore.com (off-the-grid solar components) http://www.altestore.com/learn/ (resources)
  Check out the alt E store system calculator: http://www.altestore.com/store/calculators/off_grid_calculator/
• Local Steel / Electrical Supply
• Little Giant Wagon (globalindustrial.com) or try and InStep bike trailer
• “Photovoltaic Design and Installation Manual”

• Select a small but sturdy cart with 4 wheels. Consider if you will need to take it apart for transport or storage.
• Measure and prepare the wagon for the solar frame.
• Measure and cut the flat bar / angle iron steel /aluminum frame parts to fit your wagon and solar panel.
• Make sure the angle of the solar panel is your location's latitude (37° in San Francisco).
• Tools (drill, band saw, welder, grinder, wire strippers, screwdriver, wire crimpers).
• Paint wagon with an outdoor metal paint (Rust-o-leum).
• Hardware (1/4-20 1"-2" machine screws, lock washers, bolts).
• Bolt the frame to the wagon and then bolt the solar panel on top.

• Measure and cut the steel /aluminum frame parts to fit your wagon and solar electronics board.
• Weld / bolt frame together with 1” angle.
• Use 16 gauge perf. steel /aluminum sheet for electronics wall.
• Add holes to bottom of legs to bolt to wagon floor in 4 places.
• Use webbing straps to secure the battery -- to the wagon floor.

• 60 Watt Solar Panel (20-60 watts are best)
• 12 Volt 35 AMH Sealed AGM Battery
• USB outdoor socket
• Sun Saver MPPT 15 Amp charge controller
• Sun Saver 300 Watt inverter
• Morningstar Sun Saver remote meter
• Breakers / bus bar for the solar panel, battery, and inverter (load)
• LEDs
• Label maker (label - / + wires)
• Black and Red wire

*Wire the electronics with the help of a solar electrician or take a solar class
*Review battery safety steps

• Add custom solar info graphics to attract attention and share information on solar.
• Make sure the wagon is facing South in the direct sun when charging up the battery and that the breakers are switched on.
• Use a bike lock to keep the wagon secure while charging.
• Keep the Solar Wagon in a clean dry area when inside.
• Turn the breakers off when not in use. (Do not drain the battery)
• Do not leave in the rain without water-proofing the electronics.
• Bring it to a picnic or event to play music and charge cellphones!
• Use during power outages.

Thank you:

Center for Design at Hampshire College and Skillpoint Alliance for grants that have support this project!

Check out the Solar 101 chapters at Skillpoint Alliance.