LED vs Solar Power (Offgrid)

EmeraldØsiris

EmeraldØsiris

Well-Known Member
Example:

What would be the total cost of a solar system to power 12 x 650W LED lights offgrid in a sealed grow room?

The intranet states (several places) that a 5kw system generates roughly 20kwh per day.

A 650W LED uses 7.8kwh per day @ 12 hours. 12 lights would use a total of 93.6kwh per day.

I was looking at the trina solar Vortex 670w panels for this example. If a 5kw (7.46 panels, let's call it 8) system produce 20kwh per day, then 93.6kwh would require 35 panels total to run just the lights. Considering there will be running extra fans etc. it would be correct to estimate about 38 panels. (if my math is correct) The extra 3 panels would produce roughly 7-8kwh per day.

Realistically a room like that would need a dehumidifier and an a/c.

With say 3 ft between the rows and in front and back, the size of the room would be 17ft x 30ft

The A/C would run at around 500w for that space and another 500w+ for the dehu. Probably more for the dehu. They wouldn't be run all the time either.

So say about 40 panels in total to run a decent grow of 6 4x8 trays.

Would be interested to see what type of prices people can come up with for this system. For 40 panels from Trina would according to alibaba cost $7236.

Not sure what else is needed for a solar system? Inverters? Controllers? Batteries?

I do know that 1.5 grams per watt at a total of 7800 watts makes a total of 11.7 kilos per harvest or 25 pounds. @ $500 per pound that makes $12.5k and for 2 months work that is almost double the cost of the panels. Seems like a no brainer?
 
GrassBurner

GrassBurner

Well-Known Member
If it was a no brainer, you wouldn't have to ask these questions ;-) Save the money from solar panels and buy a nice diesel generator. To run that many panels, you're gonna have a pretty elaborate and expensive system. I'd bet you're looking at $30k-$40k to theoretically provide the power you're looking for. Solar Panels are only part of the expense. I'm not sure if you want to use Solar to be stealth, but having a small Solar farm is going to be pretty noticeable.
And you're looking at around 4 months of work from seed to sale.
 
Rocket Soul

Rocket Soul

Well-Known Member
EmeraldØsiris said:
Example:

What would be the total cost of a solar system to power 12 x 650W LED lights offgrid in a sealed grow room?

The intranet states (several places) that a 5kw system generates roughly 20kwh per day.

A 650W LED uses 7.8kwh per day @ 12 hours. 12 lights would use a total of 93.6kwh per day.

I was looking at the trina solar Vortex 670w panels for this example. If a 5kw (7.46 panels, let's call it 8) system produce 20kwh per day, then 93.6kwh would require 35 panels total to run just the lights. Considering there will be running extra fans etc. it would be correct to estimate about 38 panels. (if my math is correct) The extra 3 panels would produce roughly 7-8kwh per day.

Realistically a room like that would need a dehumidifier and an a/c.

With say 3 ft between the rows and in front and back, the size of the room would be 17ft x 30ft

The A/C would run at around 500w for that space and another 500w+ for the dehu. Probably more for the dehu. They wouldn't be run all the time either.

So say about 40 panels in total to run a decent grow of 6 4x8 trays.

Would be interested to see what type of prices people can come up with for this system. For 40 panels from Trina would according to alibaba cost $7236.

Not sure what else is needed for a solar system? Inverters? Controllers? Batteries?

I do know that 1.5 grams per watt at a total of 7800 watts makes a total of 11.7 kilos per harvest or 25 pounds. @ $500 per pound that makes $12.5k and for 2 months work that is almost double the cost of the panels. Seems like a no brainer?
Click to expand...
First of all, are you basing your calculations from alibaba numbers? This is most likely a misstake as most numbers of performance are inflated.

Second: if you wanna do a classic Solar power installation with ac inverters and batteries youre kinda missing out on one thing: youre solar produces dc power already, why lose power by transforming to ac and then a driver which turns the power back to dc? The right idea is to produce one system of solar + voltage and current regulation + leds (no driver) rather than a solar to ac system and then another system of ac>driver dc> leds.
This would most likely be a custom job though which is $$$...
If youre married to the idea of alibaba solar panels then buy one to try and see what it actually outputs on a normal sunny day...
 
EmeraldØsiris

EmeraldØsiris

Well-Known Member
Rocket Soul said:
First of all, are you basing your calculations from alibaba numbers? This is most likely a misstake as most numbers of performance are inflated.

Second: if you wanna do a classic Solar power installation with ac inverters and batteries youre kinda missing out on one thing: youre solar produces dc power already, why lose power by transforming to ac and then a driver which turns the power back to dc? The right idea is to produce one system of solar + voltage and current regulation + leds (no driver) rather than a solar to ac system and then another system of ac>driver dc> leds.
This would most likely be a custom job though which is $$$...
If youre married to the idea of alibaba solar panels then buy one to try and see what it actually outputs on a normal sunny day...
Click to expand...
Yeah... $0.27 per watt: https://www.alibaba.com/product-detail/trina-solar-panels-670w-trina-vertex_1600286726223.html?spm=a2700.galleryofferlist.normal_offer.d_title.f5e822f4089nRK&s=p
If this is off, then how much? I'm trying to get realistic figures.

This guy is getting 180kwh (at best) per day from 48 x 435w panels:

Yeah, solar is DC. Yet again, seeking realistic numbers.

With solar becoming more and more efficient, as well as LED's, it would be good to realize the actual state of it today, and what is needed to get to where it can become something every grower wants.

Growing under the sun is no doubt much cheaper, but you have much less control over the environment... again, unless you have access to electricity. I'm looking at some closed system greenhouses as well using only solar.
 
EmeraldØsiris

EmeraldØsiris

Well-Known Member
GrassBurner said:
If it was a no brainer, you wouldn't have to ask these questions ;-) Save the money from solar panels and buy a nice diesel generator. To run that many panels, you're gonna have a pretty elaborate and expensive system. I'd bet you're looking at $30k-$40k to theoretically provide the power you're looking for. Solar Panels are only part of the expense. I'm not sure if you want to use Solar to be stealth, but having a small Solar farm is going to be pretty noticeable.
And you're looking at around 4 months of work from seed to sale.
Click to expand...
Find me a commercial grower who grows from seed :D
 
EmeraldØsiris

EmeraldØsiris

Well-Known Member
jimihendrix1 said:
As of January 2022 Solar costs $2.77 per watt.
Click to expand...
That's system costs?

The US has imposed a 25% import tax on solar from China. I'm interested in finding the lowest cost system before tax. Since most solar comes from China anyways, Trina solar has a good product. But from what I can see, the panels themselves are priced $0.22-0.25.

Trina 670w, China trina 670w, trina 670w Manufacturers, China trina 670w catalog

www.made-in-china.com

I'm not looking at what a solar system from your local solar supply shop and installers are asking. I'm looking at what the best system I can get at the best price is to push 12 x 650w lights 12 hours a day 365 days a year. Average cost
www.bls.gov

Average energy prices for the United States, regions, census divisions, and selected metropolitan areas : Midwest Information Office : U.S. Bureau of Labor Statistics

www.bls.gov www.bls.gov

It would be interesting to design a complete setup from LED lights to Solar. I want to think in terms of lumens per solar watt, but I'm not an electrical engineer, so I would need some input from different people.

@Rocket Soul so basically what you are saying is you don't need an inverter since it is DC to DC, instead you can connect the panels directly to a current regulator during daylight, and switch to a battery with corresponding voltage during night? The concept would then be similar to a solar powered street light, on steroids. It would definitly save on the driver costs, perhaps that cost could go towards more diodes... also it would be interesting to know how efficient the dc delivery to the LED light would be compared to powerland or meanwell.

Guess I'll ask on quora.
 
T

Treesomewanted77

Well-Known Member
EmeraldØsiris said:
That's system costs?

The US has imposed a 25% import tax on solar from China. I'm interested in finding the lowest cost system before tax. Since most solar comes from China anyways, Trina solar has a good product. But from what I can see, the panels themselves are priced $0.22-0.25.

Trina 670w, China trina 670w, trina 670w Manufacturers, China trina 670w catalog

www.made-in-china.com

I'm not looking at what a solar system from your local solar supply shop and installers are asking. I'm looking at what the best system I can get at the best price is to push 12 x 650w lights 12 hours a day 365 days a year. Average cost
www.bls.gov

Average energy prices for the United States, regions, census divisions, and selected metropolitan areas : Midwest Information Office : U.S. Bureau of Labor Statistics

www.bls.gov www.bls.gov

It would be interesting to design a complete setup from LED lights to Solar. I want to think in terms of lumens per solar watt, but I'm not an electrical engineer, so I would need some input from different people.

@Rocket Soul so basically what you are saying is you don't need an inverter since it is DC to DC, instead you can connect the panels directly to a current regulator during daylight, and switch to a battery with corresponding voltage during night? The concept would then be similar to a solar powered street light, on steroids. It would definitly save on the driver costs, perhaps that cost could go towards more diodes... also it would be interesting to know how efficient the dc delivery to the LED light would be compared to powerland or meanwell.

Guess I'll ask on quora.
Click to expand...
What are the plans for your veg setup? No matter how you plan to flower you still have to have a space for clones and then if your plan on vegging for any time you will need a whole setup for that as well. Then if you’re off grid you will need access to water so you will either need a well or have a spring on your property but will still need a holding pond or big container as a holding tank. There is a ton of stuff besides just the powering of the lights. Also you will need one heck of a battery backup just in case you’re not producing peak power all the time so you would want to make your solar system far bigger than what you need.
I don’t see solar as a viable option for growing other than maybe in a greenhouse just powering pumps for a hydro setup

to much cost and work to make it worth it then you have to sell all that produce everytime to recoup your cost and that brings another set of challenges.
Here in the states the weed market has gone to shit not worth growing for resale. Just personal use to avoid the dispensary’s or street junk.
I wish ya luck in pulling it off it sure would be awesome to see a setup able to achieve this type system.
 
jimihendrix1

jimihendrix1

Well-Known Member
How much does a 10kW solar system cost? As of January 2022, the average cost of solar in the U.S. is $2.77 per watt ($27,700 for a 10-kilowatt system). That means that the total cost for a 10kW solar system would be $20,498 after the federal tax credit discount (not factoring in any additional state rebates or incentives).
 
ProPheT 216

ProPheT 216

Well-Known Member
I've thought about this plenty. Even have good solar panels that have a efficiency rating that is top notch as far as industry standards go currently. Even chaining 6 of those together only give about 120-140 watts of charge in the sun. You would need a massive amount of panels and batteries to get through one day. 650x 12 is 7800, 650 x 16 10400 watt hours of power you would need. You would also want your panels to be able to power everything on the fly and charge the batteries with excess power. The math is doable, getting enough sun everyday even after spending the money might not be
 
EmeraldØsiris

EmeraldØsiris

Well-Known Member
Treesomewanted77 said:
What are the plans for your veg setup? No matter how you plan to flower you still have to have a space for clones and then if your plan on vegging for any time you will need a whole setup for that as well. Then if you’re off grid you will need access to water so you will either need a well or have a spring on your property but will still need a holding pond or big container as a holding tank. There is a ton of stuff besides just the powering of the lights. Also you will need one heck of a battery backup just in case you’re not producing peak power all the time so you would want to make your solar system far bigger than what you need.
I don’t see solar as a viable option for growing other than maybe in a greenhouse just powering pumps for a hydro setup

to much cost and work to make it worth it then you have to sell all that produce everytime to recoup your cost and that brings another set of challenges.
Here in the states the weed market has gone to shit not worth growing for resale. Just personal use to avoid the dispensary’s or street junk.
I wish ya luck in pulling it off it sure would be awesome to see a setup able to achieve this type system.
Click to expand...
Yeah, no doubt. There's a lot lot. I'm tryna figure out how to best design solar powered LED coverage for 6 4x8's.
 
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