Whether you live in an apartment of a house you need backup power. If / when power grid goes down, you need to power your essentials – lights, refrigerator, internet & computer equipment, etc.
There are also less common scenarios where having an emergency backup power battery is critical, such as home medical equipment.
While those cases are rare, having the power may be a matter of preserving life. Still, even if you just need to power your home essentials & fridge / freezer, you don’t want $100s of dollars worth of food to spoil or to be without light/heat for several days.
In this guide we will discuss and compare 2 primary types of domestic backup power:
- Solar PV + Lithium (LiFePo4 Battery) Battery
- Gas Generator
Both of the above, are viable options if you live in a house with a yard. If you live in an apartment complex, having a power generator is not really feasible!
With noise and exhaust gases, you cannot have it running inside. And even if you live in a first floor apartment, having it outside almost guarantees that someone will steal it.
So in my opinion, a solar + lithium battery (or solar generator) is a much better option. Still, I will look into using both types of power generators.
Solar PV + Solar Generator or LiFePo4 Battery + Inverter
Let’s get the obvious out of the way – to recharge your batteries when power grid is out, you will need solar panels. Therefore, the choice is not “IF” but “which one”? This I will cover further. But firstly I want to talk about storage of power.
1) There are literally 100s of options here, and there isn’t really the “best” one. If you don’t feel like tinkering with wires and inverters, etc, then a “Solar Generator” is what you need. However, good ones are expensive.
2) If you are more of a DIY/tinkerer type, and/or want to spend as little as possible, OR need flexibility to fit your needs – then having a separate LiFePo4 Battery + Inverter + Solar Charge Controller is the way to go.
You Need Solar Panels to Charge Your Solar Generator
Regardless of battery storage type (covered next) you will need solar panel(s) to charge it when grid goes down. Options are numerous, and I personally have different types.
1) I have 15.4 KW of grid-tied solar panels (which send excess power into the grid, and I accumulate credit).
2) I have ten 400W 72 cell panels that are for my Solar Shed, and to be “off-grid”, and will be connected to a large 48V LiFePo4 battery bank. Excess power will be used to mine crypto coins, but 4000W will provide plenty of power in an emergency situation.
3) I have a portable 200W DOKIO folding solar panel (that comes with a 12V charge controller), that can be used to charge any 12V battery (Lead Acid or Lithium, etc).
If you have a small(er) solar generator, than one or two portable solar panel(s) of 150-300W is all you need.
On the other hand, if you have a larger battery bank, than you probably want bigger 300-400W solar panels (60 or 72 cells) installed on a roof or on a ground-mounted frame, with proper charge controller, inverter, etc.
Solar Battery Storage Capacity
Regardless of what you choose from the two options above – the most critical part in a solar + battery option is the Storage Capacity, which is measured in kWh (kilo-watt-hour). Basically the bigger the number the batter. However, BIGGER also means heavier and more expensive.
kWh is a measure of how much electricity is stored in your battery. 1 kWh is enough power to power 1000W (1kW) load for 1 hour.
If your load is 2kW, then 1kWh would last 1/2 a hour. Math is pretty straight forward, except for conversion losses, but those are inevitable.
Let’s look at some examples:
Typical refrigerator runs at about 75W – 100W, thus a 1 kWh battery with 90% efficiency of inverter (900 Wh usable capacity), can power your fridge for 9-12 hours. Your laptop uses about just as much power as a fridge.
You see where I’m going with this? 1 kWh battery is not enough for most cases when power goes out, and you might not have sun for 1-3 days, so no recharging with solar either.
In my opinion, having a minimum of 3-5kW storage is essential for at least couple of days without grid power.
I will cover some simple solar + LiFePo4 (lithium-iron-phosphate) options further, but first, I want to cover the more simple, all-in-one Solar Generators.
Solar Generator Options
You hay have seen on Amazon or in Home Depot / Walmart / Harbor Freight, etc, some $300 “solar generators” … these are junk, as they are usually 300-600 Wh, and are too small to power anything bigger than an iPad / iPhone for a day or two.
I’m talking about real “Solar Generators” with capacity of 1kWh all the way to 10+ kWh modular systems.
As such, forget about local stores – they only sell “toys”. Good systems are sold through Amazon or Ebay or directly through supplier’s websites.
Each company below, has literally 10-20+ products, so listing them all is pointless. I will just say that without solar panels, the good (newer systems) form each of these companies costs about $0.80 – $1.00 per Wh … so a 2kWh Solar Generator will cost about $1,600-$2,000.
Most of these companies usually run a coupon of about 5-10%, so actual cost can be about $0.75 – $0.95 / Wh. While these coupons are not always available, they are very common!
Top Solar Generator Brands
– EcoFlow
– BLUETTI
– Jackery
– Generark *
* Generark is a relative “newcomer” in this filed, and this is not GENERAC, which is a huge manufacturer of stationary backup generators – so don’t be confused
Among these options, I feel like EcoFlow & BLUETTI are the best options, as they have been on the market for a very long time, and got rid of most of the bugs in their latest models.
Also, and this is important: they don’t require proprietary Solar Inputs, and come with standard Anderson-to-MC4 adapters / harnesses
Here are my top choices between ~ 1 kWh and 3 kWh from ECOFLOW & BLUETTI
The above systems are all-in-one, meaning they can charge the battery from home’s 120V AC outlet, solar panels and/or car’s 12V cigarette lighter.
They can also provide anywhere from 1800W to over 3500W of AC output – using a 120V pure sign-wave inverter standard, and in some cases 240V AC.
The very popular EcoFlow Delta comes with NMC (Lithium) battery, which is relatively light weight, but has lower lifetime charge-cycle count, compared to the more expensive LiFePo4 (Lithium Iron Phosphate) batteries in the more expensive versions.
Bottom line – these are portable, relatively compact “complete” systems that can be charged by solar panel(s) when there is no power from the grid.
Replaceable Battery Power Stations – Ryobi 40v & EGO 56v
These two systems are based on Ryobi’s and EGo’s power-tool and outdoor / garden equipment replaceable batteries.
Ryobi 40V Power Station has an 1800W inverter, and EGO 56v Power Station has a 3000W inverter – both are pure sign wave.
MAIN BENEFIT OF RYOBI & EGO Power Stations:
These power stations use REPLACEABLE batteries. Meaning you can have extra batteries sitting around and swap them in & out, while system is running. That means – if one battery dies – you just replace it. If batteries run low, you just swap them out.
This is a major advantage over EcoFlow, BLUETTI, etc – there, if battery dies, your unit is useless.
You can also use these replaceable batteries with Ryobi’s and EGO’s power and outdoor tools: Lawn Mowers, Chain Saws, Blowers, Trimmers, Snow Throwers, etc. So your replaceable batteries have multiple purposes, besides just energy storage for your backup power systems!
I personally own the RYOBI Power Station, because it’s the cheaper of the two, and also I own a bunch of Ryobi 40V power tools – Lawn Mower, Chain Saw, 300W portable inverter, and am open to getting other tools.
2nd reason – Ryobi 40V batteries have unbranded and very cheap alternative on Amazon & Ebay, AliExpress (not recommended), etc.
Whereas EGO batteries are very expensive (even the unbranded ones), and lock you in into EGO ecosystem, which I don’t want.
Basically I like Ryobi’s tools better than EGO. It is unfortunate though that Ryobi power station cannot be charged via solar OR while it’s turned on (UPC mode).
SOME CONS of Ryobi & EGO power stations:
Main difference besides the cost and specs – RYOBI cannot be charged with solar (unless you do some modifications and use additional equipment, such as BOOST Solar Charge Controller and a modified charger cable.
EGO can be combined with a separate solar charging block, that can be connected to MC4 solar connectors.
2nd major limitation of Ryobi – it cannot be charged while under load. EGO – I’m not sure.
LiFePo4 Battery + Inverter + Solar Charger – DIY(ish) option
Unlike the first two options – this one is the most “affordable” and gives you the most flexibility, but requires some work on your part in setting it up. In most cases it’s also not very portable.
The cornerstone of this setup is a LiFePo4 battery – this is one of the safest lithium battery technologies out there – even Tesla is switching their cars to LiFePo4! These are also the most economical battery tech in terms of $/kWh.
You have great flexibility – buying pre-made batteries with a BMS (battery management system) or even building your own batteries out of raw cells, and adding a BMS of your choice, etc.
Next component – Inverter. Here you have options from ultra budget “square wave” to mid-level pure sign wave inverters, to an all-in-one systems such as GroWatt, MPP, EG4, Renogy, etc, which combine an inverter, solar charge controller, and AC charger, and come in 12-48V DC versions.
You can basically build a system anywhere form small emergency backup, all the way up to a complete off-grid house.
However, for a small backup option – a 200-400 AH 12V LiFePo4 battery (2740-5480wH ) with a 12V All-In-One MPP or GroWatt Solar Inverter/Charger & about 400-800W of solar panels would be appropriate for most people.
The cost for these would be about $2000-$3000 including Solar Panels, wiring, and all other equipment!
Gas (or Propane) Generators: Portable and Stationary
As mentioned above (in the beginning) Gas Generators are not a good option if you live in an apartment/condo, as they must be outside due to exhaust gases.
If that is not an issue for you, having a gas generator is a good backup option with certain limitations:
1) You need to add gas all the time (every 3-6 hours).
2) Energy that’s not used, is wasted (unlike that stored in a battery – you only use what you currently need).
3) Gas generators require maintenance (oil changes, etc) and occasional repairs.
But in a bind, they will get you through an outage. Just be sure to have a sufficient gas storage (at least 10-20 gallons), and rotate your gas, as it will go bad after a year or so.
For example, I have a WEN 2000W gas generator, which I bought in the beginning of COVID, just in case… I never actually had to use it.
