Anyone know of?

[Gyll]

I am thinking about taking my company to totally renewable energy solar source. But here is the catch. I have a shop as a Gunsmith. I run a mill, lathe, tig and MIG welders, air compressor, and a plasma torch. I want a system that is completely non-dependent on the grid at all. Is it possible or is it possible but would be cost prohibitive? and if so how costly are we talking. The good news is most all my equipment is 110v. Only one TIG welder is 110v or 220v.

 

[Jim Burrow]

In my opinion, you will need many solar panels and a controller/inverter that can handle the power draw of your equipment. To give you an example, I have (6) 300 watts 39-volt panes and ISC of 9-amps per panel. I have them configured as three branches and each branch consists of 2 panels in series. This is in the theory of course under ideal conditions. I get on the average 65 to 70-volts on most days here in California and could in theory get ISC (of 27-amps) but have never reached that due to the location of my panels from my controller and force to use different lengths of cable (cord) to my controller.

With respect to my MPPT all-in-one PIP-2424lv-MDS controller/inverter, it is rated for 2300 watts. But it doesn't like my microwave pulling 1800 watts or the clothes washer and dryer. (I'm running 120Vac with this system.

The point I'm getting at is you would need, in my opinion, a much bigger controller/inverter or multiple controllers in parallel with many more pannels than what I am using just to run the Tig and MIG welders for example.

In my experience in the very long past using a Tig and a Mig welder, would dem my lights and everything else in the shop when plugged into the utility company grid.

However, don't get discouraged based on my newbie experience, there are a lot of guys in this forum that are really smart dudes in this solar stuff.

 

[time2roll]

What is your monthly kWh usage?

 

[Gyll]

In my opinion, you will need many solar panels and a controller/inverter that can handle the power draw of your equipment. To give you an example, I have (6) 300 watts 39-volt panes and ISC of 9-amps per panel. I have them configured as three branches and each branch consists of 2 panels in series. This is in the theory of course under ideal conditions. I get on the average 65 to 70-volts on most days here in California and could in theory get ISC (of 27-amps) but have never reached that due to the location of my panels from my controller and force to use different lengths of cable (cord) to my controller.

With respect to my MPPT all-in-one PIP-2424lv-MDS controller/inverter, it is rated for 2300 watts. But it doesn't like my microwave pulling 1800 watts or the clothes washer and dryer. (I'm running 120Vac with this system.

The point I'm getting at is you would need, in my opinion, a much bigger controller/inverter or multiple controllers in parallel with many more pannels than what I am using just to run the Tig and MIG welders for example.

In my experience in the very long past using a Tig and a Mig welder, would dem my lights and everything else in the shop when plugged into the utility company grid.

However, don't get discouraged based on my newbie experience, there are a lot of guys in this forum that are really smart dudes in this solar stuff.

Thanks, I will keep that all in mind.

 

[Gyll]

What is your monthly kWh usage?

I'm moving into a new home that has a nice shop on it so I will have to wait for 3 months to get that info. But in the shop, I'm using right now was 3549 kWh for the month

 

[Lt.Dan]

3549kwh per month equates out to 118kwh per day, which is ALOT. You would have to have roughly 25kw of solar panels and enough battery power to last you through the night! If you use most of the power throughout the day, you would probably need 35-40kw of solar, which is a sh*t load of panels lol

Not saying its not possible.

40kw of solar panels
6x MPP Solar LV6548 All in One unit
50kwh of Battery power

 

[Hedges]

PV panels are cheap. That 25kW of panels might cost you all of $8000.
Of course if you can figure out where all that power is leaking and reduce it by half or two thirds, that would be good. If you have electric heat, consider fossil or renewable fuel, or a heat pump? But heating with PV in winter doesn't seem practical. If you burn fuel, look for "CHP", combined heat and power such as a diesel generator with waste heat used for the house.

Batteries are expensive and a hassle. If you can install grid-tie PV with net metering, you could make the same number of kWh as you use, but draw from the grid at night.

Inverters to deliver 5kW average throughout the day, peaking at something like 10 kW or 25kW, is not unreasonable for a home system but will cost at least a few grand.

You can build an off-grid or grid-backup system of the capacity you describe, but it will cost a few ten's of thousands of dollars.

I would use 2 to 4 Sunny Island (3-phase or split-phase), several Sunny Boy over-paneled with East and West facing panels. DIY LiFePO4 batteries appear best value and lowest up-front cost of all options. Or, if I started with a DC Solar surplus trailer, I'd use the FLA forklift batteries that come with it until they wear out, hopefully 10 to 15 years from now.

 

[schmism]

40kw of solar panels
6x MPP Solar LV6548 All in One unit
50kwh of Battery power

Id say that's a good ballpark to napkin math a project like this.

PV - $25k
inverters - $9k
batts - $5K
misc (wireing, etc) - $3k
generator $6-$10K

Id expect $50k-$70k for a budget.

 

[Alphacarina]

Batteries are expensive and a hassle. If you can install grid-tie PV with net metering, you could make the same number of kWh as you use, but draw from the grid at night.

But usually you end up selling your daytime excess power to the grid for about 25% of what it's worth and then when the sun goes down, they sell it back to you for 100% of it's value, so with battery storage you can save your own surplus daytime power for use at night and that can be a big plus - True, battery storage is expensive too, but in the long run it might be better than losing 75% of what your excess is really worth. Unfortunately, the power company makes all the rules

Don

 

[NMNeil]

3549kwh per month equates out to 118kwh per day, which is ALOT. You would have to have roughly 25kw of solar panels and enough battery power to last you through the night! If you use most of the power throughout the day, you would probably need 35-40kw of solar, which is a sh*t load of panels lol

Not saying its not possible.

40kw of solar panels
6x MPP Solar LV6548 All in One unit
50kwh of Battery power

As the OP say's it's for his shop, is there a need to calculate for nighttime use?

 

[Hedges]

But usually you end up selling your daytime excess power to the grid for about 25% of what it's worth and then when the sun goes down, they sell it back to you for 100% of it's value, so with battery storage you can save your own surplus daytime power for use at night and that can be a big plus - True, battery storage is expensive too, but in the long run it might be better than losing 75% of what your excess is really worth. Unfortunately, the power company makes all the rules

Don

For me, utility rates are something like $0.15, $0.30, $0.45/kWh.
I see best prices for DIY LiFePO4 about twice as expensive as PV (each amortized over lifetime or 10 years, whichever is less.)
That doesn't even include battery inverter cost.

So to me, I'm better off installing 3kW of GT PV and giving the utility that power during low rate times, then using the credit to get back 1 kWh during peak times.
It would cost me at least as much to install 1 kW of PV, charge batteries, and deliver 1 kW of PV to utility during peak times.

So I'd rather use the utility as a 33% efficient battery than buy and install a 100% efficient battery.
What I do have is enough battery to get through the night in case of a grid failure.
With my excessive PV, with grid down, during the day I power all loads including A/C while recharging and floating the battery.

 

[Lt.Dan]

As the OP say's it's for his shop, is there a need to calculate for nighttime use?

If he's working out of a shop he owns, chances are, he's working late nights as well (as I see most business owners do), or atleast after 6pm where PV output is minimal at best. He will need battery power to run that.

The grid tie is an option, but like where I'm at, I buy 1kWh for $0.14, and you sell back at $0.03/kWh. Doesn't seems super reasonable, but does it make sense to spend $5-10k on batteries? That's up to you.

Also you gotta think that Hybrid/Grid Tie inverters cost much much higher than a quality AIO unit, so it might make sense to spend money on batteries instead.

Again, all up to you. I personally won't Grid Tie unless they make it very easy to DIY.

 

[Jim Burrow]

But usually you end up selling your daytime excess power to the grid for about 25% of what it's worth and then when the sun goes down, they sell it back to you for 100% of it's value, so with battery storage you can save your own surplus daytime power for use at night and that can be a big plus - True, battery storage is expensive too, but in the long run it might be better than losing 75% of what your excess is really worth. Unfortunately, the power company makes all the rules

Don

just a side comment. not all areas will let you connect to the grid and sell back the excess power. In my area, it is against the law to connect to the grid that way. You can of course connect to the grid to power your controller and supply power to the load when needed. You just can't have the power flow back into the grid meter.

 

[Forbisher]

Id say that's a good ballpark to napkin math a project like this.

PV - $25k
inverters - $9k
batts - $5K
misc (wireing, etc) - $3k
generator $6-$10K

Id expect $50k-$70k for a budget.

He has grid power in the shop now so why would he need a generator?

 

[schmism]

He has grid power in the shop now so why would he need a generator?

I want a system that is completely non-dependent on the grid at all.

per OP's request. There will be days of extended no/insufficient sun which will require a backup source of power.

 

[Forbisher]

The $64.000 question is why do you want your company to be totally renewable energy solar source?

I am thinking about taking my company to totally renewable energy solar source. But here is the catch. I have a shop as a Gunsmith. I run a mill, lathe, tig and MIG welders, air compressor, and a plasma torch. I want a system that is completely non-dependent on the grid at all. Is it possible or is it possible but would be cost prohibitive? and if so how costly are we talking. The good news is most all my equipment is 110v. Only one TIG welder is 110v or 220v.

 

[Supervstech]

3500KWh

Wow, that is a lot.

Are there areas of use you can conserve?

Keep in mind, commercial power often isn't measured... it is estimated based on footprint.
And the power company estimates in their favor.

Try getting your own meter to validate usage.
It will be useful for your solar anyway... then start measuring individual use cases, and see where you can reduce.