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Mataman
07-16-2008, 12:02 AM
What is the formula to compare line voltage to low voltage electrical costs?:confused:

Lite4
07-16-2008, 12:15 AM
There really isn't a formula. A watt is a watt whether it is 12v or 120v. What you look at is lamp efficiency. For example lumen output. A 20 watt mr-16 in a 12v system will probably give you 4 times the lumen output of a standard incandescent line voltage bulb, depending on what you are comparing it to of course. You have to look at the photometrics and compare. The real savings though comes when you start comparing installation costs between the two.

INTEGRA Bespoke Lighting
07-16-2008, 12:25 AM
A KWh consumed is a KWh consumed. It does not matter if you use 100w at 12V or if you use 100w at 120v.

Take your load in watts,
Divide by 1000,
Take the remainder and multiply by the number of hours in operation,
Take the result and multiply by the (real) cost of a KWh of electricity in your market.

Example. 600w trans / 1000 = 0.6 X 6 hours per night = 3.6 KWh x $0.14 per KWh = $0.50 per night.

Now, make sure you figure out the "real" KWh cost of electricity in your market. This would include all of the taxes, fees, delivery costs, debt retirement charges, etc etc that the power company adds to your bill. Here the "real" cost of our electricity is about $0.14 per KWh.

steveparrott
07-16-2008, 03:15 PM
The figure most often quoted is that low voltage lighting consumes about 1/3 the energy of 120-volt lighting.

This is a very rough estimate based on the several factors including:

Luminous efficacy (lumens/watt) - 12V halogen is about 15 lm/w; 120V incandescent is about 10 lm/w - a 50% savings.

More appropriate lamp wattage selection: outdoor floods are typically 75W or 150W or more; 12V lamp choices of 20W, 35W, 50W, etc. This means that appropiate brightness levels are easily achieved - a 35W tree light easily replaces a 150W flood (about 75% savings).

Better control of light spread - more efficient use of lumens dependant on lighting design and fixture design.

There's a lot of variation in the above factors so an attempt to nail an actual number is difficult.

Mike M
07-16-2008, 07:46 PM
A quick reference sheet on figuring the cost to operate a particular system (assuming you know the approx. total wattage) is available from CAST, I have it on a photocopy, I think. You check their website resources.

Mataman
07-17-2008, 10:15 PM
... The real savings though comes when you start comparing installation costs between the two.
ahhh, I'm screwed. There's an electrical company in town that is destroying the low voltage market. They're putting in bollards for $100 each,,, installed! I guess they're trying to keep payroll up since the housing market has crumbled.

bids I've lost to them last month(their fees);
- 18 bollards and 5 spots for under $3,000
- 19 spots for $2500
- 14 paths, 3 wall wash, 12 spots, guessing $4500 @ the most

The home owners/HOAs are more worried about upfront costs. Of course when they see a $3,000 bid and then a $10,000 bid, they're figuring years and years to recoup the difference.

The figure most often quoted is that low voltage lighting consumes about 1/3 the energy of 120-volt lighting.

This is a very rough estimate based on the several factors including:

Luminous efficacy (lumens/watt) - 12V halogen is about 15 lm/w; 120V incandescent is about 10 lm/w - a 50% savings.

More appropriate lamp wattage selection: outdoor floods are typically 75W or 150W or more; 12V lamp choices of 20W, 35W, 50W, etc. This means that appropiate brightness levels are easily achieved - a 35W tree light easily replaces a 150W flood (about 75% savings).

Better control of light spread - more efficient use of lumens dependant on lighting design and fixture design.

There's a lot of variation in the above factors so an attempt to nail an actual number is difficult.
I've tried to explain this to the customers over and over but it's like they don't believe me. Kinda like when concentrated liquids came out, nobody believed that you could get the same results with less liquid. Now in this case, less watts.

Thanks for your quick responses.

steveparrott
07-18-2008, 07:39 AM
What is the formula to compare line voltage to low voltage electrical costs?:confused:

Hearing that the electrical guys are beating you up on price, you'll need to take price out of the equation by strongly differentiating yourself as a lighting designer.

I assume that you deliver better lighting design, that you are passionate about landscape lighting, that you are an artist, that you transform the homeowner's nighttime experience! That you use the highest quality and best performing products. The value of all that is recognized by your target high-end market.

Your task is to effectively communicate how you are very different from the electrical guys. You need a great website, great presentation material, a good demo kit and learn to speak with great passion about your design ideas.

Let the electrical guys take all the jobs from penny-pinching homeowners. You don't need that work, you need high-end homeowners who are willing and able to pay for value.

Lite4
07-18-2008, 09:57 AM
ahhh, I'm screwed. There's an electrical company in town that is destroying the low voltage market. They're putting in bollards for $100 each,,, installed! I guess they're trying to keep payroll up since the housing market has crumbled.

bids I've lost to them last month(their fees);
- 18 bollards and 5 spots for under $3,000
- 19 spots for $2500
- 14 paths, 3 wall wash, 12 spots, guessing $4500 @ the most

The home owners/HOAs are more worried about upfront costs. Of course when they see a $3,000 bid and then a $10,000 bid, they're figuring years and years to recoup the difference.


I've tried to explain this to the customers over and over but it's like they don't believe me. Kinda like when concentrated liquids came out, nobody believed that you could get the same results with less liquid. Now in this case, less watts.

Thanks for your quick responses.

You are definitely fishing your gear a little too deep in the pond. If all you seam to be encountering are SUCKERS and other bottom feeders, you need to change your bait for the appropriate fish and raise it from off the bottom so you can present it where the trophy fish live. Trophy bass and trout always seem to share the water with suckers and mud dogs. You just need to be a skillful enough angler to know how to catch them. (Sorry for the fish analogy) EC's will only be able to put out product like that for so long. I can't imagine they are making much of any money unless they are cutting corners somewhere and even then, Yikes, Thats gotta be some POWERFUL ugly lighting. Keep on Fishin.

JoeyD
07-18-2008, 12:49 PM
You are definitely fishing your gear a little too deep in the pond. If all you seam to be encountering are SUCKERS and other bottom feeders, you need to change your bait for the appropriate fish and raise it from off the bottom so you can present it where the trophy fish live. Trophy bass and trout always seem to share the water with suckers and mud dogs. You just need to be a skillful enough angler to know how to catch them. (Sorry for the fish analogy) EC's will only be able to put out product like that for so long. I can't imagine they are making much of any money unless they are cutting corners somewhere and even then, Yikes, Thats gotta be some POWERFUL ugly lighting. Keep on Fishin.

I love that anology.....I might have to steal it!! LOL

Mataman
07-18-2008, 06:22 PM
HA! You guys kill me!:drinkup:

Actually, these all have been in some very high dollar areas. The bollards gig is very snooty, only problem is that there is an engineer and GC that I know and are certified "Cheap". The lots alone start @ 650,000 but average 1 million for water front. Most of the houses on the water front sit on two lots.
Get this, they told me yesterday that they plan on putting those
"energy saving" bulbs in all the bollards to cut costs.
What I need is to find an HOA that specifies in their bylaws that all homes must have lighting and the board members will all be clueless nurses.:cool2:

The Lighting Geek
07-18-2008, 09:24 PM
Hearing that the electrical guys are beating you up on price, you'll need to take price out of the equation by strongly differentiating yourself as a lighting designer.

I assume that you deliver better lighting design, that you are passionate about landscape lighting, that you are an artist, that you transform the homeowner's nighttime experience! That you use the highest quality and best performing products. The value of all that is recognized by your target high-end market.

Your task is to effectively communicate how you are very different from the electrical guys. You need a great website, great presentation material, a good demo kit and learn to speak with great passion about your design ideas.



Great point Steve! That is exactly how I see it.

Mataman
07-18-2008, 10:55 PM
HA! You guys kill me!:drinkup:

Actually, these all have been in some very high dollar areas. The bollards gig is very snooty, only problem is that there is an engineer and GC that I know and are certified "Cheap". The lots alone start @ 650,000 but average 1 million for water front. Most of the houses on the water front sit on two lots.
Get this, they told me yesterday that they plan on putting those
"energy saving" bulbs in all the bollards to cut costs.
What I need is to find an HOA that specifies in their bylaws that all homes must have lighting and the board members will all be clueless nurses.:cool2:

oh I didn't mention that this one was for an HOA; pathway to tennis court, couple oaks and entrance to the mailbox area.

It's tough to do what Steve recommends when you're dealing with a superintendent vs a homeowner. If I was a big dawg like you guys, my reputation would precede me (btw, nice article in the mag Mr Lighting Geek).

As far as being passionate, yeah, I think I do ok in that area. I've always gotten good remarks on my fixture selection, layouts and demos, but when the old man sees the estimate, I can see/hear him adjusting his dentures.

Do I need to bump it up a bit,,, sure, why not, there's always room for improvement.
Am I an artist,, maybe a starving artist but I feel that I some skills. I just need more opportunities to play.

Target high end; is there anything other than? :cool2:

Here's a few pics of the last one I did. Lost the day too fast and my pics are pure amateurest.

This tree is the 1st of many large trees along a winding driveway. My initial plan was to uplight all 8 trees of similar size but they cut my budget in 1/2! So they got the 1/2 the show. Looks pretty good coming down the road though.
http://i5.photobucket.com/albums/y160/Mataman/DodsLighting026.jpg


The homeowners really don't care for lawn art and could care less about this fountain and was considering taking it out. I refused to light their property unless they let me light it up. They changed their minds after they saw it and it's one of the last things you see before you get to the house. I probably didn't put a soft enough bulb in but you live and learn. OR I look back now, and I could've done some downlighting from a nearby tree and that would've soften the light on the center of the fountain and then lose the shadows on the house. Blew that one.
http://i5.photobucket.com/albums/y160/Mataman/DodsLighting030.jpg

This one is a couple paths setback on the driveway along with a few up lights. It's much more appealing in person.
http://i5.photobucket.com/albums/y160/Mataman/DodsLighting0281.jpg

I really wasn't satisfied with the backyard. It was so dark back there and I think I originally had like 20 fixtures back there but that got cut down too. There's a dock and nice walkway behind the pool but it got cut out.
http://i5.photobucket.com/albums/y160/Mataman/poolII1.jpg
http://i5.photobucket.com/albums/y160/Mataman/DodsLighting0341.jpg


Please feel free to critic, I'm not beyond improvement. I've also been trolling here for some time and have a lot of respect for 97.82% of you guys. :rolleyes:

The Lighting Geek
07-18-2008, 11:57 PM
I see something in your pics (not referring to the quality of your pics, theyr'e fine) I see disconnected light or at least that is what I call it. I would try to get the trees connected with a soft lighting bridge to carry or connect the different trees and also to keep the fountain from looking so bold. One way to soften a hot item is to surround it with softer light, helping to diminish the harsh contrast you get from lighting a singular item. I realize you were limited in scope, but that struck me right away. If want to know more about bridges, continuity, and techniques I highly recommend Nate Mullen's book. I am probably using the terms from the book without realizing it, hopefully correctly...LOL! It is a very practical book to learn from, I learned a lot from it and still refer to it. The terminology will help you tremendously in building credibility with your clients and separate you from the typical ECs and landscapers. You will sound and look like an artist (which we are) in comparison to someone who is just installing fixtures that put spots in our eyes for a couple of hours...LOL

The Lighting Geek
07-19-2008, 12:08 AM
I had a job some time ago who cut my budget in half, so I asked them to let me use the lights I still had to light the front yard and for them to wait for the back yard. When they saw the front, 2 things happened. They added more lights to complete the front and they called me back in a month because they could not wait to get the backyard to look like the front. I find most of the time clients have no idea what great lighting looks like and they are basing the fixture count on the crappy lighting they have seen, a light in front of every tree and runways of path lights, etc. Just thought I would throw this out there, maybe it will help.

Chris J
07-19-2008, 09:03 AM
When you are being picked to death by a customer, it's better to do one zone complete rather than eliminate placements throughout the property. When I'm allowed to do a complete design, whether it be the front, back or a particular area, the customers always finds more money to do the rest. The point is not to do a half-a## job throughout. Do one area at a time, and do it right, or tell the customer to find someone who is willing to sacrifice quality for shoddy work.

INTEGRA Bespoke Lighting
07-19-2008, 10:02 AM
[QUOTE=Mataman;2424944]
This tree is the 1st of many large trees along a winding driveway. My initial plan was to uplight all 8 trees of similar size but they cut my budget in 1/2! So they got the 1/2 the show. Looks pretty good coming down the road though. I would recommend that when the client needs to save some dough on the installation that rather then cut out fixtures from any given zone, or the entire system, that you cut out entire zones. It is better to do two out of four zones properly then to do a half job in four zones.

The homeowners really don't care for lawn art and could care less about this fountain and was considering taking it out. I refused to light their property unless they let me light it up. Think about what you are saying here... This is something that obviously the clients don't have a lot of interest in. Why push? You need to cater more to the whims and desire of your client and not push so hard for what you think is best. Bill Locklin summed it up best with his "WHY LIGHT?" protocol. If you listen more to your client and then provide them with what they need and want, you will make a better impression. No matter what it looks like at night, they still have to live with that 'lawn art' all day long, only now they are hesitant to remove it because they have invested more money into it. If you had catered to the client there, you could have used that infrastructure elsewhere and they would probably be more happy in the long run.

Great lighting systems are so much more then the sum of their parts... with a bit more focus on your sales techniques, and maintaining the design focus and integrity you will do just fine.

Mataman
07-19-2008, 06:54 PM
Excellent! Thanks for all the advice.

Tommy Herron; I will research that book.