For the last few years at Christmas, I’ve dressed up a scrub conifer that resides on one of the two rock outcroppings adjacent the highway with a string of twinkle lights. The solar powered twinkle lights were OK but didn’t last that long into the evening and they really weren’t that obvious unless you were looking for them. Was a pain for the old guy here to try and string the lights around the tree on a fairly severe slant. Taking them down inetivibly ended in their destruction. Decided there were better options but I wasn’t sure which direction to go.
In the meantime, I bought a 9 FT Outdoor stranded light Christmas Tree that ran an automated program to make the lights perform 14 different patterns. Set it up on the deck because it was too tall for any room but the living room and plugged it in. Pretty cool. I decided, while assembling the tree on the deck, that there was no way this could be assembled on the rock outcropping without considerable difficulty. New location would be the dam with the reflection off the pond in my direction and the ability to see the tree from the highway through the trees.
Bought a toy version of a wind turbine thinking wind might be a good method to power the Christmas Tree distant from the house. Utter failure as the turbine was Chinese junk. Spotted a deal on a 12V 5Ah battery, a controller and a 30W solar panel so I decided to try solar. Added a photovoltaic switch for dusk to dawn coverage and a 12V to 110V inverter into which I plugged the tree. Put it all in a clear plastic storage bin with a lid to weatherproof it. Worked to power the tree but I discovered the battery only had approximately a 3 hour capacity.
Back to the web and quickly discovered the key was Watt Hours. I knew what the Christmas Tree used in watts so I used an online calculator to figure out what battery capacity was necessary to run the tree for any given period of time. Then I figured out what solar panel wattage was necessary to replenish the battery charge used by the tree overnight. I rounded up and settled on a 12V 50Ah LiFePO4 battery and 2 100W solar panels to replenish the battery capacity used. The solar panels were cheaper than I would have expected, the controller was remarkably cheaper, and the battery was more expensive. Put it together in another plastic storage bin using the existing inverter. The new controller had a dusk to dawn setting so that made the connections all that much easier. Speaking of connections, this was the 1st time I’d seen or used MC4 weatherproof connectors for low voltage wiring and I was impressed with the ease of use for these connectors.
I’ve run the solar powered Christmas Tree on the deck for about a week and have been able to see via the controller what it has used in watt hours and what the solar panels can feed back into the battery during the day. The battery is topping out during recharge so I have plenty of capacity and solar refill. The weather has been extremely close to what what we’d normally expect around Christmas. I was concerned the cold weather would affect the battery but it doesn’t seem to be any issue when temperatures are above zero. The panels have been able to replenish all the power used in the night even when we’ve been very overcast. Looks like I can disassemble, pack up for late November and have a great chance of the Christmas Tree working as expected come the Holidays.
