Solar power is all the rage in prepping, homesteading, and rural living circles and has been for many years. Solar sounds like the perfect backup power solution, right? You don’t need any hard-to-store fuel, there is no dangerous exhaust, and, best of all, solar is silent.
But can solar batteries power your critical appliances during a power outage? And is it worth the time, energy, and money to buy a solar generator or put together a solar array for backup power?
Table of contents
- The Pros and Cons of Using Solar as Backup Power
- What Equipment Will I Need to Build My Own Solar Power System?
- Or You Can Buy a Solar “Generator”
- Solar Power is a Great Addition to Preps, But Is Not The End All, Be All
The Pros and Cons of Using Solar as Backup Power
- Solar power units have no exhaust and can be used inside.
- They are silent and won’t alert others to your presence or the fact that you have a power source.
- As long as you have sun, you have fuel.
- Most solar generators and batteries have enough capacity to power small electronics, LED lights, and small appliances for a significant length of time.
- Solar panels need many hours of sustained, direct sun to charge. Solar power may not be your ideal backup power source if you live in a heavily wooded or frequently clouded area.
- Unless you have huge banks of batteries, your solar energy storage capacity is going to be limited. Thus, your backup power may be drained rapidly depending on your energy needs.
- Unless you have many square feet of solar panels, your recharge rates may be slow.
- Charging cannot happen at night.
The current thinking is that solar power is the perfect power backup for small appliances and/or temporary power outages. If you need to run power-intensive appliances like refrigerators, freezers, AC units, or space heaters for any length of time, you may be better off with a traditional generator, OR you will need a very substantial solar array and battery bank.
Read a discussion of fuel generators here. You can also get a Generator Self-Assessment to help determine which backup power is best for you.
What Equipment Will I Need to Build My Own Solar Power System?
The short, non-technical version is you will need one or more solar panels, one or more batteries to store the energy, and an inverter to deliver the electricity correctly to your appliances. The more batteries you have, the more energy you can store. The more solar panels you have, the faster you can recharge those batteries. It gets a lot more technical than that if you want to build your own system, but that is the nutshell version.
With any solar array, it’s a balancing act between the size of your system, the speed at which you can recharge, how much power you need, and how long that power can last. There is no perfect system out there. It all depends on how much power you need vs. how big of a solar system you’re willing to build. Or buy.
Or You Can Buy a Solar “Generator”
Another option with the same result is to simply buy a solar “generator.” It’s called a generator, but it’s really just a nicely packaged, very portable solar battery charged by solar panels or a wall outlet.
Advances in technology, as well as more competition in the industry, have made these units more practical and affordable than they have ever been. They still aren’t cheap, however.
Another drawback of ready-made generators is that your storage capacity will be limited to the size unit you buy, whereas building your own system allows you to expand your capacity.
How Long Does It Take to Recharge A Battery With Solar Panels?
How long it takes to recharge a battery with solar panels is a crucial question because if the power is off for an extended amount of time, you will need to recharge your battery with your solar panels. In the past, this could take so long that solar power sources weren’t useful for more than brief power outages.
Fortunately, times have changed. I can only speak directly to the unit that I have, but using the four solar panels it comes with, it only takes me 5-ish hours to recharge my generator when/if conditions are optimal. That’s the same amount of time it takes me to charge it via my wall outlet, so I certainly don’t save any time with the solar panels, and the outlet is more convenient!
I have heard about generators taking 20-60 hours to charge via solar panels, but perhaps that had more to do with the size of the panels. Obviously, the amount of charging time directly depends on how many solar panels you have and your weather conditions. I have four panels and live in a sunny state.
How Can I Calculate the Energy My Appliances Use?
Calculating the energy use of appliances can get very technical, but I will spare you the trance-inducing explanation of volts, amps, and watts here. Don’t get me wrong, these are very important concepts, and there are many excellent tutorials out there if you’re serious about using solar energy. For our purposes today, however, I will gloss over the technical details.
For now you just need to find the wattage of your critical appliances so you will have a general idea of how big of a solar system (or generator) you will need. Or you may discover that a solar system won’t work for you. Please do your own research before you buy or build anything since this can be an expense well into the thousands of dollars.
Luckily, even without understanding the physics of electricity, you can find out how much energy each of your appliances uses. This requires knowing how many WATTS they use.
Calculating How Many Watts an Appliance Uses
To do this, you can:
- Look for a sticker on the appliance (volts x amps = Watts),
- Look in your user manual,
- Search your appliance’s wattage usage online,
- Use an appliance load tester, or
- if you have a solar generator, you can do what I did and individually plug each appliance into your solar generator to measure wattage. (Yes, I confess I bought a solar generator without doing my homework.)
My solar generator has a handy display that tells me what each appliance draws and how much time it can be powered by what’s left in the battery. It also has a big indicator of how much battery is left. Generators for dummies, for sure.
An Unpleasant Surprise: Key Appliance Energy Hogs
It was eye-opening for me to discover how much energy different appliances use. More importantly, I discovered how short of a time my solar generator can power them. Some things were fine, like electronics and fans and my grain mill. Some bigger conveniences were electricity hogs, however. Like my toaster oven and electric teakettle. Fortunately, I can easily live without those during a power outage.
The unpleasant surprise, however, was my small space heater. It’s something that I may need to use if my power goes out in the winter, but my 1534-watt-hour battery can only run my heater for an hour! I’m thankful I discovered this before I counted on it to keep my pipes from freezing.
I simply didn’t understand wattages and battery capacity. Now I sort of do. At least I understand it enough to know what I can and can’t run off of my solar generator.
For example, you can run a mini fridge for several hours because it cycles on and off, but my big side-by-side refrigerator/freezer will require either a traditional generator or a much bigger power bank than I have.
Real World Examples
The following are examples of appliances at my house that I tested with my solar generator. I hope these examples give you a ballpark idea of how much energy some appliances use. Each brand and size of appliance at your house is going to be different, so use these examples as a general guide.
I have a Jackery 1500 Pioneer solar generator that can handle up to 1800 watts of draw and will give me 1534 watt-hours of battery. That means I can run anything that draws up to 1800 watts…but not for long. Not even a full hour.
On the other hand, lower-watt appliances can be run for a long time even if you plug them in simultaneously.
These numbers are as calculated by my generator.
|Appliance||Wattage||Aprox. Run Time|
|iPhone||27 watts||46+ hours|
|iPad||28 watts||45+ hours|
|Laptop||45 watts||25 hours|
|Box Fan||37 watts||28 hours|
|Crockpot||250 watts||5 hours|
|Vitamix||250-400 watts||5-4 hours|
|Electric Grain Mill||400 watts||3 hours|
|Electric Teapot||875 watts||2 hours|
|Space Heater (small)||1230 watts||1 hour|
|Toaster Oven||1500 watts||<1 hour|
How Do I Get the Power to My Appliances?
Some may scoff at this, but before I bought a generator, I was so clueless I didn’t know that generators have regular outlets on them. I’m not sure what I thought happened; special extension cords, maybe? Turns out, you just plug your appliance into the outlet on your generator or inverter like you would on your wall. Yes, I know. Duh.
Is Using Solar Power Dangerous?
Solar batteries and generators are quite safe. There is no exhaust, unlike a gas-powered generator, so you can use them inside your home.
Also, even if you overload a solar generator with too many appliances at once, the good ones will trip and not damage your appliance. Something to research before buying one, however. Obviously, your DIY system won’t have that safety feature unless you include it.
Can I Build My Own Solar Array?
There are many videos and articles explaining how to do this. I don’t enjoy projects like this and am guaranteed something will go wrong, but building your own system may be just the ticket to getting what you want.
Solar Power is a Great Addition to Preps, But Is Not The End All, Be All
Solar arrays/generators are a great addition to any preparedness plan. They are perfect for keeping electronics and small appliances running for a significant amount of time (depending on your load, etc, etc). However, they are generally NOT going to be useful for running refrigerators, freezers, or larger energy-sucking devices for long periods.
They are particularly handy for smaller charging jobs for which you wouldn’t want to fire up a big generator. Things like phones, a laptop, or a grain mill.
Solar power should be part of a comprehensive power outage plan. To help you develop a plan for your family, grab The Survival Mom’s Family Power Outage Survival Handbook here.
Do you have a solar array or generator that has worked well for you? I would love to hear about it.