Back when I started experimenting with solar set-ups, panels and charge controllers (to regulate the charge to protect the batteries and panels) were relatively costly and only available in my location by special catalog order. Deep cycle sealed 12v “marine” or golf cart batteries (for solar and other charging) and dc-to-ac power inverters (for converting battery power to run household corded devices) were and are available at many Walmarts and truck stops.
Although my first portable solar power set-up was a noticeable cost for an AmeriCorps member (maybe $600 total, or about a month’s living stipend), creating a portable solar charging and powering option wasn’t prohibitively expensive. I worry for people who are convinced that solar power must involve a major financial investment to be viable, and particularly given the components readily available today.
I currently use the following Amazon purchased set-up to charge devices and power some household items most days (Ii’s not powerful enough to run the fridge, for example) — and to be ready for possible power outages, or to take on the road:
- Instapark 30 Watt Mono-crystalline PV Solar Panel, with included charge controller and alligator clips (approx. $70)
- ExpertPower 12v 20AH sealed rechargeable lead-acid battery (approx. $40)
- A 500 Watt DC-to-AC power inverter with included alligator clips and a cigarette lighter adapter (approx. $30)
That’s about it. I recently shared this approximately $140 approach with Native Renewables to consider as an option with their work with tribal communities and remote, off-the-grid households. For our meeting, I carried the entire set-up into a neighborhood coffee shop in a plastic laundry tub.
Yes, there are likely more portable and integrated, better quality and possibly less expensive set-ups available, but as I shared in my push light post, I think there are real benefits in buying separate low-cost components with multiple possible uses. Simply to consider:
- a power inverter with alligator clips can be fairly easily attached to different 12v batteries, such as a car battery (but obviously use caution and consider the potential risks when attaching to any battery). Personally, I don’t like to use DC-to-AC power inverters through vehicle cigarette lighter plugs (noting the possibility of tripping fuses or damaging the outlet and related vehicle electrical components). However, I have used an inverter with alligator clips to run corded hand tools directly off of an old 12v work truck starter battery, with the parked truck running (to maintain a battery charge) and the inverter secured in such a way that it should not fall into the running motor or easily detach from the battery (possibly creating an arc). I keep a higher capacity (750 Watt) power inverter (approx. $45) and extension cord in the truck, noting the wattage requirements of the hand tools I am using. This set-up — running my old truck as a power generator of sorts — might be enough to power our small fridge in an emergency;
- I have used the square Instapark 30 Watt Mono-crystalline PV Solar Panel, with included charge controller and alligator clips to maintain the charge on a very weak and seldom used 12v sealed truck starting battery. In my case and with the old truck parked in a very, very sunny area, I was able to keep the panel inside the truck and on the dash and still achieve a trickle charge (as indicated with the lights on the included charge controller) — running the cords out a window crack and under the closed hood. I would detach the solar panel from the battery before starting the old work truck.
- There are definitely bigger 12v sealed rechargeable lead-acid batteries available via Amazon, etc., but the 12v 20AH sealed rechargeable lead-acid battery that I purchased is relatively light weight and thus more portable, and it has considerable density / stored power for its size. I actually have two of these approx. $40 batteries, solar charging one outside while using the other inside with an inverter.
To be clear, I am talking about LEAD-ACID 12v batteries: Two words that should trigger at least some concern.
The batteries I solar charge (it takes a while to do so, given the panel is only 30 watts) are designed not to spill or to be easily opened, but I still check them for bulges and leaks. Moreover, I only use this set-up in a well ventilated room when I am there to monitor it and no kids are around, and I do not store batteries inside our home.
Additionally, I keep baking soda (as an acid neutralizing base) where I store and use my batteries, and I should probably use gloves when I use or move them as another precaution. I always wash my hands immediately after handling any battery and avoid touching my eyes or face. To note, charged batteries can spark or possibly shock when attaching a load, so make sure any inverters or devices are switched off and use caution when attaching to a battery. Typically, I have on at least some form of eye protection — as these are LEAD-ACID batteries after all. When the sealed 12v lead-acid batteries I use eventually no longer hold any charge, I take them to O’Reilly Auto Parts for recycling.
Right now, I’m using the set-up photographed to write this blog post. The cooling fan built into the power inverter is making a slight buzz — noting that heat is a by-product / waste of the dc-to-ac power inversion.
For USB charging, it is possible to skip the DC-to-AC inverter, connecting to the battery with a cigarette lighter plug socket with alligator clips (approx. $10) and USB cigarette lighter charger (approx. $5, and available at most convenience stores). Likewise, there are portable solar panels with built-in USB charging outlets on the market (approx. $30-$150), but I prefer not to charge my devices directly from the sun.
Is mine the best solar set-up that can be bought for $140? Almost certainly not (noting some review complaints about the quality of the panel I use, the gauge of the included wiring and the functioning of the included small inverter) — but mine is pretty easy, and I have been using it successfully for a few years in different capacities.
Has my solar investment (maybe $1000 over nearly 20 years) “paid” for itself? Ys, in the sense that I have learned about solar power and some of the basics of home and vehicle electricity and lead-acid battery safety through the process of reading about and putting together very basic “off-grid” solar arrays.
Maybe I have saved a few bucks on energy bills over the years, and especially by drawing from battery power during peak hours such as 4pm until 9pm. In terms of “energy independence,” I have been able to fully charge various USB devices (including an AA battery charger and a portable shower) as well as run key household appliances (a wifi router and radio) even on some cloudy days (mono-crystalline seems to be the way to go) with my sub-$200 set-up.
Shout-out to Steve @ Think Save Retire for his roaming FIRE lifestyle and going much bigger with his solar investment!