Off Grid Solar. 1kW System could run....?

I've been reading a little about off grid solar panel systems.
I know they are available in 1kW, 2kW, 4kW....
but I don't know what a 1, 2 or 4kW system can power, constantly and consistently ???

I understand the concept of kWh's.
I know that using a 1000w appliance for 1hour equals 1kWh (1 kilowatt hour).

Example-
2 x 1000w on for 12 hours (out of 24) would equal (12 + 12 =) 24kWh
2 x 600w on for 18 hours (out of 24) would equal (0.6 x 2 x 18 =) 21.6kWh
That would be 2 x 1000w on 12/12 flower
and 2 x 600w on 18/6 veg.
The 2 x 1000w and 2 x 600w would equal 45.6kWh


Then there's the fans (inline and circulation)
the water pumps (irrigation), the air pumps (oxygenation),
dehumidifier and heaters.

Would a 4kW system be able to power 4000w at any one time???
Could I run 3 x 1000w and a 600w light???

Or would 4000w be the max?
(like when the ISP's tell you how fast their broadband is....
then you discover they've told you the absolute max speed and it never gets that fast, really!
It would be like a pint of milk being UPTO 1 pint.
and, sometimes, when you open it there would be hardly enough to whiten a coffee.

you can not run a setup like that you need the amperage usage for everything and then how many amps the solar/wind power will produce that is why some people have large battery banks that hold the extra power

also you can run power inverters in sequence o if you have an 1800w you inline the wires and it will produce 3600w and so on
no matter what you will need to have a battery bank to store extra power

grow2grow said:

you can not run a setup like that you need the amperage usage for everything and then how many amps the solar/wind power will produce that is why some people have large battery banks that hold the extra power

also you can run power inverters in sequence o if you have an 1800w you inline the wires and it will produce 3600w and so on
no matter what you will need to have a battery bank to store extra power

Click to expand...

I cannot RUN the system
or I cannot calculate it on watts alone???

My assumptions are based on watts because the Solar Power Systems are rated by the kW
and my appliances are rates, primarily, by watts.
The amount of amps, volts or other units of measurement are unknown to me -
But I would research them if it was necessary.

Watts are power ... Amps are current. Appliances are based on usage, ie kW ... But you setup your house based on current, or the amount of drawn amperage. Ie, on extension cords have a max amperage, it is the amount of amperage that can be used ... Your circuit breakers are based on amps 15 or 20 usually.

you may have power during the day but where technology is lacking is in the storage of the power. Also, excess power can be sold back to the electric company. The power has to be cleaned up. Even the electric company has cleaner power that can be supplied to customers who have the need for it. I use the word "clean" loosely. Storing the extra unused energy is expensive.

A lot of your question would best be answered by product reps. Ie i have a 6000w generator thats does not men i can run 6000w/hr ... It is a % of that .... You are asking good questions but a lot more info is needed.

North -
Provide some links to units you're looking at. Solar was a wasteland as far as solid information just a decade ago. Now you can buy solar kits at Costco fer cryin' out loud. And you can google for virtually complete kits.

Big question - are you thinking of off-grid or on? If you're thinking of an off-grid system then you have to have a properly sized battery bank. A large battery bank is expensive. And there's no way around the efficiency losses from storing the electrons in the batteries, then using those electrons later. You have battery losses, wiring losses, and electronic device losses (charge controllers, inverters, etc.)

I googled "4kw off-grid solar package". Picked a hit and went there. Your sig says England, so sorry this is US, but it still gives you an idea. I picked the "Large Off-Grid Home Package 3" just to get an idea of what you're looking at. It's listed as 4.5KW.

$13,336 for the basic package. NOT including batteries. Go further down the page for battery options, which add several thou to the sticker.

To address your question about whether a 4KW system can power 4KW at a time, the answer is "probably not". Or at least "not for long" before the inverters shut down. My guess is that very large loads would be limited first by the inverter (or inverters) maximum sustainable output, then by battery bank, wire sizing, etc.

Kits like this are rated by maximum panel output. In this case, on a cool sunny day the panels are theoretically capable of 4.5KW output. But that's not what you need to know, really. Take a look at the estimated monthly output based on 5 hours of sun per day. Up to 611KWh. That's their estimate, which doesn't take into account a week of solid cloud, smog, summer heat (heat lowers panel output), panel shading from trees, etc.

31 days X 24 hours = 744 hours. 611 KWh divided by 744 hours = .82 KW. So a relatively large system like this one is capable of providing something like .8KW per hour if you had some sort of constant, 24/7 load on it. Of course we're not interested in a constant, 24/7 load. Maybe something more like 18 hours on and 6 hours off? With a robust battery bank, and in a sunny climate, I'd guess you could safely run about 1 to 1.5KW of lights for 18 hours a day. That's a fair amount of light if you're all LED.

Bottom line: solar is still expensive. I wish it wasn't because I've wanted to live in a solar-powered house my whole life.

Oh, yeah, we didn't even talk about generators. That's another big expense. All your growing efforts could easily be ruined by a week of bad weather so I think a robust generator would have to be part of the plan.

The place....Northern England is best served in alt. energy by your own hydro operation, avoid storing the power in an expensive battery bank use the duck pond and store the water ..most diy hydros work in the 4-8 kw/h range, excess feed to the national grid as a way to pay for the high startup costs

Generators ...? most electrical engines can be re wired to work as electrical generators, for theses type of operations, marine parts work very well indeed

I've seen a few eastern grows with a grow op in a hydro lake, hiding in a chicken farm...?

No. Renewable energy never put out 100% of what they are rated at. Solar panels brake down over time and never put out max due to it relays on the sun. The weaker the sun the less power produced, the stronger the sun the more power.

When it comes to power even for ac. You relay on the voltage and amps that it puts out. You can't run some thing that draws say 10 amps on a 8 amp circuit. Your going to damage it.

The only way to get into solar power at the cheapest is to get a grid tie peace of hardware that feeds power into your plugs and distributes to the whole house. You should be paying no more then $2.50 per 1w for solar power.

Don't look into gas powered generators. Not only do most not live past around 208 days of usage every day but the repair cost will be alot ontop of the cost for the gas to use it will be to. This doesn't also include the oil that you need to use to.

My opinion if you go off-grid combine wind and solar to get the most possible power. That way if the sun is hiding behind clouds hopefully you have a decent wind blowing...