Can someone just check my components list please?

[cfreark]

Hi All,

I'm just getting my feet wet with DIY solar. Occasionally my power will go out (Xcel-grid) and I'd like to be able to power some household lighting, router, computer, monitor, TV, etc. for up to 2 or 3 hours until the power comes back on (worst case scenario). I'm assuming it isn't going to be good for my batteries to just sit waiting for those power outages, so I'm prepared to run a few small-draw items off this small backup system on a regular basis to allow the batteries to discharge and recharge. Here are the components I have so far:

A single Hanwha 305W panel (I've attached the data sheet)
2000W Continuous, 8000W Maximum Pure Sine Wave Inverter (60hz)
MPPT Tracer10-40A MPPT Charge Controller
Two DataSafe AGM batteries (12HX505) 12V, 119AH each, parallel connection (238AH total)

Will these components go together to provide the backup power I need? Can I add to my battery bank if I need to? By the way, I'm in Denver Colorado and get pretty good sun.

Thanks in advance - I really enjoy reading your posts, I'm learning a lot!

Chris

[jflorey2]

A single Hanwha 305W panel (I've attached the data sheet)
2000W Continuous, 8000W Maximum Pure Sine Wave Inverter (60hz)
MPPT Tracer10-40A MPPT Charge Controller
Two DataSafe AGM batteries (12HX505) 12V, 119AH each, parallel connection (238AH total)

Some notes -

The "8000W Max" inverter - don't waste your money. Your batteries can't supply that much current (over 600 amps) - and even if they could you'd probably start a fire. I'd stick with a good ~600 watt sine wave inverter like the Suresine.

I would add an AC charger instead of the solar panel. It will be more reliable overall and your batteries will last longer. Several places sell good inverters/battery chargers. If you want to do both solar and AC charging, that will also work.

Do not forget circuit protection. Fusing on the batteries at the very least; ideally appropriately rated breakers for all circuits. Don't forget fusing/breakers on any lines that come off the main busbar rated for the wiring that's attached to them. That means if you have 2/0 wire going between inverter and battery, and 18 gauge wire going to your charge controller, you need two different fuses.

Also I couldn't help but notice that you basically want a UPS. Consider getting a UPS and adding solar charging; might be simpler and safer for you.

[cfreark]

Some notes -

The "8000W Max" inverter - don't waste your money. Your batteries can't supply that much current (over 600 amps) - and even if they could you'd probably start a fire. I'd stick with a good ~600 watt sine wave inverter like the Suresine.

I would add an AC charger instead of the solar panel. It will be more reliable overall and your batteries will last longer. Several places sell good inverters/battery chargers. If you want to do both solar and AC charging, that will also work.

Do not forget circuit protection. Fusing on the batteries at the very least; ideally appropriately rated breakers for all circuits. Don't forget fusing/breakers on any lines that come off the main busbar rated for the wiring that's attached to them. That means if you have 2/0 wire going between inverter and battery, and 18 gauge wire going to your charge controller, you need two different fuses.

Also I couldn't help but notice that you basically want a UPS. Consider getting a UPS and adding solar charging; might be simpler and safer for you.

"and even if they could you'd probably start a fire" ?????????

I went with a 2000W inverter in case I need to run my fridge off it. I went with PSW because I like the improved efficiency of PSW vs. MSW and I don't want to take ANY chance of damaging the new fridge by using MSW.

Not sure what you mean by "I would add an AC charger instead of the solar panel". I'm already running a 4.3KW grid-tied system and have one extra panel that I want to use for this project.

[SunEagle]

Save your money and don't purchase the battery, inverter or the extra panel. Go get an inverter style generator to run your refrigerator and electronics. It will be cheaper and allow you to run more than the batteries and solar panel will provide.

[Logan5]

If you have not bought any of this junk, Don't! if al you have is an extra panel from your install, save it in case of future damaged panel. do not buy any 12 volt inverters. They are mostly junk. If you plan to run any refrigeration you need a 24 volt plus system by wiring 2 X 12 volt batteries in series. Keep in mind AGM batteries are fixed lifespan batteries, depending on the batery quality 300 to 500 cycles, under the best of charge conditions, Solar provides less than ideal charging conditions.

[jflorey2]

"and even if they could you'd probably start a fire" ?????????

If the inverter is really going to run at 2000 watts and surge to 6000 watts, then you will be dealing with currents of 160/660 amps. Those are not currents those batteries can support. 4/0 wiring would handle those surges, but 1) I suspect you're not going to use 4/0 wiring (or compatible protection devices) and 2) neither the terminals of your batteries nor the terminals of the inverter would be likely to survive such power levels.

So in a way it's good news that your battery will not supply that, because the rest of your system likely couldn't deal with those currents safely.

"But they advertise that the inverter can do that!" Yes, they do. Caveat Emptor. Most people never push those power levels because their battery will not supply such power levels.

Like I said, consider a smaller inverter that can carry its rated load. The Morningstar inverter is a nice one. If you really want big power numbers the Prosine series is well built - and will give you 1000 watts, has terminals and wiring devices that can handle the current the inverter is rated for. AND has a transfer switch. And will surge to 1500 watts.

Or a Prosine 2.0 - which will output 2000 watts for real, and has a transfer switch, and has a built in charger. But make sure you have the cabling and protection to handle those currents, and you will need a bigger battery bank if you want to approach 2000 watts. (And you should NOT try to make a larger battery bank by paralleling a lot of batteries together.)

Or go with your original inverter. If they are like most Chinese inverters, they will be good to about 500-600 watts - but you will likely have issues with efficiency, EMI and heating.

Not sure what you mean by "I would add an AC charger instead of the solar panel". I'm already running a 4.3KW grid-tied system and have one extra panel that I want to use for this project.

It will help prolong battery life. If you lose power at 5pm, run for a few hours and drain your battery down to 40%, and then power comes back at 8pm, and the battery sits at 40% all night - it won't last as long. If you start charging again as soon as you regain power, then you extend battery life. AC chargers are cheap insurance.

Like I said before, if you really want a UPS with solar, that might be a cheaper/easier solution for you. All the stuff above is going to be expensive and require care and maintenance.

[foo1bar]

Save your money and don't purchase the battery, inverter or the extra panel. Go get an inverter style generator to run your refrigerator and electronics. It will be cheaper and allow you to run more than the batteries and solar panel will provide.

I agree.

and if you really want to do solar, you can still do that - just do a grid-tie system (maybe get the one with "secure power supply" that can power for small loads when the grid is offline.)

[SunEagle]

I agree.

and if you really want to do solar, you can still do that - just do a grid-tie system (maybe get the one with "secure power supply" that can power for small loads when the grid is offline.)

The OP has a grid tie system. But if he wants a low cost high power emergency backup system it would be better to get an inverter type generator instead of batteries, PSW inverter and more panels. They would be more expensive and not provide the emergency power needed for the length of time needed when it was needed. Even much better than a Secure Power Supply which only works when the sun is shining.

[cfreark]

It seems like some of you equated "getting my feet wet" with newbie/moron. Not appreciated.
Thanks to those of you who actually tried to help.

[SunEagle]

What we are trying to tell you is that a solar /batter system is not worth "getting your feet wet".

Sure getting a grid tie system is probably the best bang for your buck when it comes to investing in solar pv but when it comes to an emergency backup power system you might as well throw your money away because it is really a waste. You will get more output to run your loads during a power outage from a generator then from a solar/battery system. There is no arguing the point any farther.

But if you don't care about wasting your money we can help you build a system. Just don't cry when you run out of "watts" when you need them and loose your food when the frig stops working.