Converting from Fluorescent .... vs SOLAR

[msalari]

Hello Mr Sunking, Mike, SunEagle good day.
The house we just moved into has a nice insulated shop (24x30') with 100amp service. (I'm converting it to 'man cave'.)
The previous owner installed 16 x 4foot ballasts (2 bulb) = 32 florescent bulbs. Some are 32W, most are 40Watts. By my math that is about a kilowatt of power every time I turn the lights on, and the thought of that kills me.
I could take the path of least resistance, which is probably convert the bulbs to LED style (I know about the ballast rewire). But the shop lights are unsightly so I have been also playing with the idea of just replacing all the lights with LED fixtures.

Then, a friend suggested solar...

Lets say I want to use it for 2 hours per day, that will be conservatively high.
I have about $1500 budget, and thinking that I am going to spend about half of that to buy LED fixtures and bulbs.

How much would I expect to pay for solar panels, controller, batt and inverter to run lets say ~600Watts of LEDs?
*Keeping in mind I have the luxury of switching back to AC in a pinch

Thanks guys

[cebury]

I doubt the path of least resistance is rewiring the existing but taking replacing with led bulbs (not my suggestion) but taking them down and putting up led shop lights.
[url]https://www.costco.com/Feit-Electric-4

[cebury]

Lost paragraphs above.

Costco Feit LED light

If you decide to keep an unsightly shoplight look, the above lights were onsale at Christmas last year for 20 off. That equates to $20 per 4' led light. They are 3700 lumen, 42 watt. Not the most efficient out there, but with the discount and features below it was a great deal. They have pluggable ends, so link chain easily, super lightweight easy to install for one person, you can drill through the reflector to mount (dont need hanging wire). If there is no discount this year, you may find a more efficient one for an equivalent price with a name you can trust.

When I installed them, they were significantly brighter than the 6 T12 units I replaced. But the variables with those: bulbs wear, must be paired to wear evenly, and the ballast wears.

Im sure the folks you name above will be by soon enough to give you the expensive bad news on the batteries and panel end (esp. ongoing costs).

[AzRoute66]

Let's be clear, the 're-wiring' consists of removing the ballast and extra wire. At least that is all it was for the LED tubes I went with. Oh, and new tombstones (the connector/holder on the ends of the tubes).

The main drawback to a system that has batteries - is that it has batteries.

[SunEagle]

I doubt the path of least resistance is rewiring the existing but taking replacing with led bulbs (not my suggestion) but taking them down and putting up led shop lights.
[url]https://www.costco.com/Feit-Electric-4

IMO replace all of the fluorescent lights with LED tube type. You can perform a total fixture replacement or remove the ballast and wire the fixture to handle LED tubes that use 120v.

Once you have reduced your electric foot print by going with LED you can then think about installing a solar pv system if that makes financial sense. Otherwise keep the shop on the gird and you will still end up saving money to pay for those LED's lamps.

[AzRoute66]

Something I'm not quite clear on. In my garage/shop/mancave (all in one), the same circuit powers my lights and outlets. Was it your thought to separate those? Would that be physically easy to do? Easy to revert back (as you say)? Perhaps just a consideration.

To your original question (I hate when I skip that). 600W x 2 hours use = 1200Wh/day. 1200Wh / 4 sun-hours (a guess) = 300W x 1.5 fudge factor = 450W panels. With a 24 V MPPT controller, 450W / 24V = 19A so a 20 A charge controller would do in a 200 Ah system. 40A for a 400 Ah 12 V system. I think a 750 - 1,000 W inverter is a good choice. Costing those out should put you in the ballpark. Don't forget your wires, fusing, etc.

[sensij]

2 hours per day of a 1 to 1.3 kW load is 2 to 2.6 kWh / day (all 32 W tubes vs all 40 W tubes).

Let's say just 3 days autonomy since you have some control and it is not a critical need.

Battery = 6 - 7.7 kWh
PV system = 600 - 780 W (making a ton of assumptions not worth digging into at the moment)

Let's go with 24 V for this.

Battery = 250 Ah - 320 Ah

Trojan L16RE-A has 325 Ah, so four of those to get to 24 V, at something like $325 / ea = $1300

Figure panels at 0.50 / W, so another $300-$400 there.

Charge controller is another $100 - $200.

Wiring, racking, etc... doesn't matter, you are already over budget.

With respect to the suggestions above, replacing 40 W fluorescents with 42 W LED's won't save energy if every tube is replaced, but maybe you can get by with fewer fixtures because they would each be brighter.

[azdave]

I thought about a conversion to LEDs for my shop too. The 24 x 30 garage has a total of 16 dual-lamp 48" florescent T8 fixtures. They are switched on and off in groups of four and I rarely have anything but the first row turned on over my work benches. That row is switched on by a motion detector that also detects the ambient light level before powering up. The other 3 banks of lamp are switched manually and I'll bet I don't turn those on but 1 hour per month at best.

Looking at the cost to convert and the limited hours in use, a conversion to LED would never pay for itself in my lifetime. I would have to use the lights many, many more hours per day to begin to approach an acceptable ROI.

Installing anything PV with batteries for your application is quite simply ridiculous when you have grid power already installed. It would be a complete waste of money to power it with off-grid style energy.

If it were me, I would not even bother converting the existing lamps to LED unless I wanted a certain look for a man cave. My shop is where I work. No room for man cave frills.

[Logan5]

If noise may be an issue. consider some of these LED shop lights have a hum or buzz, I would not be concerned in my situation but if you had a number of these noise could become excessive.

[cebury]

With respect to the suggestions above, replacing 40 W fluorescents with 42 W LED's won't save energy if every tube is replaced, but maybe you can get by with fewer fixtures because they would each be brighter.

Im not fond of tube replacements, the units I suggest arent the greatest but they are 42W as a lighting unit (2 tubes) for the 3700 lumem. It is very much brighter than the older dual t12 ballasts (I wrote t8) which consume about 90watts for the dual unit and in theory shouldnt it be approx. 2500 lumens per bulb? In reality Im betting it isnt even close due to brand and various component degradation. I definitely needed fewer for same lighting amount of old t12 shop lights, at least for now.

[sensij]

Im not fond of tube replacements, the units I suggest arent the greatest but they are 42W as a lighting unit (2 tubes) for the 3700 lumem. It is very much brighter than the older dual t12 ballasts (I wrote t8) which consume about 90watts for the dual unit and in theory shouldnt it be approx. 2500 lumens per bulb? In reality Im betting it isnt even close due to brand and various component degradation. I definitely needed fewer for same lighting amount of old t12 shop lights, at least for now.

Ah, sorry, I missed that the power of the LED fixture was for both tubes, not just one. So, yeah, the conversion would cut the power in half, for higher quality light.

[SunEagle]

I thought about a conversion to LEDs for my shop too. The 24 x 30 garage has a total of 16 dual-lamp 48" florescent T8 fixtures. They are switched on and off in groups of four and I rarely have anything but the first row turned on over my work benches. That row is switched on by a motion detector that also detects the ambient light level before powering up. The other 3 banks of lamp are switched manually and I'll bet I don't turn those on but 1 hour per month at best.

Looking at the cost to convert and the limited hours in use, a conversion to LED would never pay for itself in my lifetime. I would have to use the lights many, many more hours per day to begin to approach an acceptable ROI.

Installing anything PV with batteries for your application is quite simply ridiculous when you have grid power already installed. It would be a complete waste of money to power it with off-grid style energy.

If it were me, I would not even bother converting the existing lamps to LED unless I wanted a certain look for a man cave. My shop is where I work. No room for man cave frills.

I have replaced about a dozen fluorescent tube lamps with LED type in my home and garage.

One thing I noticed is that while the original fixture usually includes 2 x 34watt T8 lamps, I was able to replace them with a single 18watt LED tube that fit into a T8 position and actually get more then enough light.

So not only will going to LED type lamps reduce your lamp wattage but based on the amount of light you really need you can reduce the number of lamps which also decreases your total fixture wattage used.

[msalari]

Most excellent, thank you folks
thank you Cebury for the costco LED shop light link - if I decide to keep the shop light look, that seems like an excellent way to go.
i have a trip to China in 2 weeks so I will plan to do some shopping there too
cheers

[SunEagle]

Most excellent, thank you folks
thank you Cebury for the costco LED shop light link - if I decide to keep the shop light look, that seems like an excellent way to go.
i have a trip to China in 2 weeks so I will plan to do some shopping there too
cheers

Just be careful of what you purchase overseas. Sometimes electrical equipment will have a different voltage and Hz rating then what we use hear in the US.