Off grid solar system for construction site
18 Jul 10 | Solar ElectricThis was a unique and fun project. A fellow is constructing an off grid home in upstate NY. His idea, since the house is going to be off grid anyway, why not put in a temporary system to power tools and such while building the structure. When the house is completed, the system can then be moved inside. He is also living onsite in a yurt, so having electricity available to charge laptops, run the well pump and other things that most of us take for granted would be a great side benefit.
To start, he purchased a portable saw mill and began clearing the lot. Using trees he cut down on site, he built this temporary power shed to house the inverter, charge controller and batteries:
We used a bit of left over rubber roof membrane to water proof the roof prior to installing the PV panels. The PV panels are Sharp NU-235F1 mounted on Unirac rails.
The inverter is a Xantrex XW-6048 with a XW-MMPT solar charge controller. Also used are the XW power distribution panel, the XW control panel and generator start panel. Since this system is going to be used in the finished house, we choose the larger inverter. This house has a well that is 380 feet deep and uses a Goulds 1 1/2 HP submersible pump. This pump is the largest single draw in the entire system, starting surge of about 5,000 watts and using 2,100 watts when running. The 6 KW inverter is able to handle this without problem.
The batteries are 16 Surrette S-530 flooded cells.
The wall between the batteries and the inverter has 30 pound roof felt to act as a corrosive barrier between the batteries and the electronics. Ventilation is copious. The tarp is placed over the opening when the system is not in use.
The house itself is in progress, with the foundation completed and the floor slab being prepared for pouring soon.




