Power consumption of laser projection. Open discussion.

[James Gardiner]

Hi all,
Power consumption has become a critical discussion on the purchase of new projectors.

I have been involved in attempting to compare 2 different vendor offerings.
My general conclusion is that different vendors have advantages and disadvantages in different models, But in general it would appear to be a wash. Being, no one vendor has any significant advantage over the other. Some models when compared be better, but others worse.

I would like to get other, non-conflict-of-interest based, input from other knowledgeable readers of this forum.

It also does bring up the question of. "How do we objectively compare Apple and Oranges"
For example, each vendor quotes power usage based on different approaches to obtain them.
For example, one turns on a projector and sets it to 100% lamp. Takes a reading.
Another does a generalised approach based on average power over the life of the projector based on maintaining DCI-spec brightness and primaries and having to raise the power over the 10 years to archive it.
There are also differences in comparing total hours as different vendors base it on different ambient temperatures.

Personally, I don't like the subjective and unproven approach. But I would like others to share wisdom on how to make comparisons.

In general, laser is quite new and the expectations vendors portray and real file results are not proven. Personally, the vendor who has been at this the longest, appears to portray a realistic expectation or laser life based on temperature and power settings. But with next-generation system using different technologies, it is hard to know if the same understandings apply.

In this difficult calculation, I tend to put weight behind proven record backing.
Keen to hear other opinions, and if anyone out there has real world experiences to share.

[Frank Cox]

At risk of showing my ignorance here:

Does it matter?

I just have a single screen theatre and a xenon lamp, but when we went through the big covid shutdown my power bill didn't change in a really significant way from the power bill that I get when I'm playing a movie every night.

My take-away from that was that the power consumption by the projector (popcorn machine, etc) isn't a particularly important factor when put up against the power required to run the rest of the building.

[James Gardiner]

When you are buying 30 projectors for a number of cinemas. Yes it does matter.
In general, power savings on Laser are about 60%-70%. Power usage costs have gone up considerably in many regions.
So yes, it does matter. It can be a considerable savings per site. (i.e. pays itself of in 5-7 years compared to staying with xenon)
ue to this, it is a significant presales discussion. But in general, Frank, I to think it's pretty much equivalent across the board. They are all using similar technologies and parts now.
Personally I feel picture quality, ease of support and proven reliability are far more important factors.
But I'm just a lowly engineer type. Hidden away in the back room, not to be seen or appreciated...

[Marcel Birgelen]

At risk of showing my ignorance here:

Does it matter?

I just have a single screen theatre and a xenon lamp, but when we went through the big covid shutdown my power bill didn't change in a really significant way from the power bill that I get when I'm playing a movie every night.

My take-away from that was that the power consumption by the projector (popcorn machine, etc) isn't a particularly important factor when put up against the power required to run the rest of the building.

If it matters comes down to your cost structure. But there are significant reductions to be realized.
For example, a 19k lumen DP4K-19B will consume about 6 kW if you run it at 90% with a 4K lamp. Meanwhile, a 20k lumen SP4K-20C will run at about 2 kW if you run it at about 90%. So, your laser projector consumes about 1/3rd of the power for a comparable image brightness. Meanwhile, the laser image will probably be perceived as even brighter, due to the improved contrast of the laser image.

Also keep in mind that if you put 6K of electrical power into a machine, almost all of it comes out of in form of heat. Getting rid of this heat, depending on your local climate, can also cost significant power, especially if you need to deploy active cooling.

Last but not least, energy costs vary wildly between countries. I'm paying currently about 1.5 times what you're currently paying per kW for example.

[Carsten Kurz]

I know some sites pay techs to change their xenon bulbs. While this can usually be paired with other maintenance jobs, this can add to the cost of Xenon considerably. Another important factor of course is screen size and 3D use. Replacing a 6kW xenon projector with an RGB laser will have multiple benefits costwise. We operate UHP based projectors since 2013, no 3D, on a mid size screen, and I don't see any benefit. Our lamp power and exchange cost is already very small. Of course, at some time in the future, we WILL need to buy a new projector because UHP has been EOL. But not in the close future.


What I hate about buying into budget lasers is that in 2024, they still show no to little improvement in basic image quality, namely, contrast and color fidelity.

[Leo Enticknap]

I know some sites pay techs to change their xenon bulbs.

In my neck of the woods almost all of them do apart from the big chains that have in-house techs, and places that run UHP-illuminated projectors. As a result of these costs, some independents and lower budget operations run their lamps until they start to flicker (or some other fault materializes), regardless of warranty hours.

Another issue to factor in is installation costs for new installs. Not having to run three-phase power or install forced air lamphouse exhaust ducts is a significant up front cost saving; as against which, laser safety regulations limiting seating density near the back of the room can have long-term revenue implications.

A still largely unknown factor is how long laser illumination sources actually last. Manufacturers typically predict 20K to 30K hours, but only the earliest laser projectors are now approaching that. There is one room I look after with a laser phosphor projector that has now done well over 20K light hours (the interval at which replacement of the phosphor wheel is recommended), all of them on full power. The last time I was there, I found no significant degradation of light output and color balance. So it maybe that these predictions are significantly pessimistic.

[Steve Guttag]

In terms of raw electricity, Barco and Christie seem to be significantly lower cost on their laser projectors than NEC (Sharp). This is going by the faceplate current rating. The difference is less so on the lower-end of the range (lumen wise) but if you get up to what I would consider NEC's flagship projector, the NC3541L, it wants a 30A circuit (200-240V) and I believe it used to be 40A. Even the NC2041L (same projector, 1-light source so 20K lumens instead of 35K, wants 17.5A. Compare that to a Barco SP4K35 needing 20A for their 35K lumen projector. NEC has an obnoxious number of fans in their systems...54 of them in the 3541L...that is going to consume power and move dirt about.

Regardless, that is still significantly less power than to fire a Xenon lamp to the same lumen range. You'd be up to 3-phase power and 30A to get a 6KW-7KW lamp up to those levels.

Then there is the other aspect to laser...they can, normally, vented to the booth rather than cutting a hole in your roof to vent outside. So, the projector because another heat-load to the HVAC system rather than something that sucks air out of the theatre and has to be replenished...plus, when you get rid of the exhaust, you also get rid of a source of condensation in the hotter months. So, the electrical benefits of lasers provide two opportunities.

I believe Frank saying that he hasn't seen much impact on his single screen theatre. It will depend on the wattage and a single projector may not be a driving force in his electric bill. But the same could be said if you switched one incandescent light bulb to LED in your house. You aren't going to likely see this huge drop. But, as others have noted, once you make the switch, across the board, the effects are cumulative.

So, yes, if you are a 10-plex, you will notice the drop in electricity much easier than a single screen...unless you are a Drive-In or other very large screen system. As you move above a 3KW lamp for light, the benefits to laser light on your electric bill (and changing lamps) improves, geometrically. Xenon lamps, as you move above 3KW start lasting shorter periods of time and costing much more, and are less-and-less efficient with their light as their arcs get larger.

As for longevity...I've been staying VERY conservative. I'm trying to start projectors at less than 50% power on their least efficient format. The enemy of lasers are heat. The cooler you can run them (lower power, cooler environment), the longer they are going to last. Time will tell how well all of this plays out. Who knows, the lasers might outlast the other parts of the projector. The is another wear item in many laser projectors...the phosphor wheel. Anything mechanical like that has a limited life...in the motor and the wheel itself. So, the cost and frequency of replacement will, eventually factor in. Conversely, I think xenon reflectors are expected to go way beyond their realistic life. If they are in 1-piece, people keep using them. Take a 10-year old projector and change its reflector and see how much more light you get. The decay on that stuff is so gradual that you don't notice it (this is true for the rest of the optical path, as well). Change a light engine out...you'll probably get 20-30% more light just from having clean optics.

[Gordon McLeod]

In Canada the hydro bill is in two parts delivery fee and KWh used We had a 8 plex with very old used in poor optical shape serries 1 barcos all using the lens in them that came from a USA site and as such they all had a terrific amount of scaling to fit the screens they all had 2K and 3K xenons before the theatre finaly was demolished we converted the entire complex to NEC 1000c's and amazingly there was little electrical bill saving. Also during the winter all xenon machines vent into the return air and during the summer to the outside. The loss of the heat being dumped into the return air caused a increase in plant heating costs

[James Gardiner]

Great comments, and especially Steve, I have heard there are a lot of poor presentations happening these days as, yes 10+ year projectors with old light engines that are not sealed. With external exhausts pulling new (Contaminated air) all the time... They are seriously compromised compared to the initial installation. At some point they WILL have to be replaced. I am starting to see considerable major faults needing significant costs to rectify. Faults that independents have to deal with on the spot or have a screen go dark. Spending significant money on fixing projectors that may not last 2 more years.

The rocky times and questionable future is causing a lot of cinemas to hold off on overdue upgrades. Its not doing the industry any favours. We go on about giving quality presentation but then are behaving this way. It's disappointing for cinema culture.
I have no solution for this, but gee It's hard to watch.

In any case. I started this thread as, those who are taking the plunge and upgrading are hit with very confusing doublespeak coming from integrators trying to sell them projectors. Using the confusion above that is only frustrating and introduces significant friction to the sales process. It's not helpful. (But may be intentional, unfortunately.). Still, I would like a narrative developed that makes this issue less difficult to navigate for those cinemas investing into the future of cinema.

I know the vendors are reading this. I have intentionally avoided naming any in an attempt to take a position of impartial commentary. I hope they are getting the message.

[James Gardiner]

Just a comment here.
It must be noted, based on the technology used in the laser projectors. Different laser wavelengths produce more heat than others. So the formula, specifically in the smaller projectors, Blue/Blue, Blue/Red etc. have different heat envelopes even if using the same amount of power. It's a major reason it's very difficult if not impossible to compare the projectors on paper. Considering cooling requirements are a key factor to the overall cost of running them. It is due to this, I feel real work experience is the only way to really know. But then again, some of these products are so new, that experience is still yet to be developed.

I feel this is a topic we need to share here into the future due to the misinformation and confusion that can gravitate to this gap in our understanding of this aspect of laser projection.

[Barry Floyd]

FYI... as our Barco DP2K-23B projectors start to age out, we've looked at replacing them with laser. One thing we found that we actually qualify for is the REAP (Rural Energy for America) grant program. If the equipment replacement can show a significant engergy savings (30%-50%) the grant will actually cover 50% of the cost of the equipment replacement. As an independant theater owner in a rural area, it makes sense for us. Now we just have to decide how much longer we really want to be in the movie business. A new projector is a 10 year commitment for most of us.

[Steve Guttag]

The rule of thumb for the more efficient systems is that the laser will run at about 33% of the electricity of its xenon counterpart. So, I'd think that you'd qualify for your grant money. If you are good with Barco, and want to reuse that lens, then the SP4K-25B is the closest replacement (or the SP4K-25C with a B lens mount...once it returns to the market...probably in 2025). The SP4K-25C has a 16A nameplate versus your 30A one on the DP2K-23B. So...based on that alone you are at about 47% savings. The "B" version only has a 14A faceplate so a 53.5% savings. If you want to stick with 2K...the SP2K-25C is the closest equivalent but you'll need a new lens as I'm pretty sure they don't offer that projector with a B lens mount option...plus, the chip size is significantly smaller...meaning you likely won't have the zoom range.

[Leo Enticknap]

In any case. I started this thread as, those who are taking the plunge and upgrading are hit with very confusing doublespeak coming from integrators trying to sell them projectors. [...] I know the vendors are reading this. I have intentionally avoided naming any in an attempt to take a position of impartial commentary.

In that case, it reads like making accusations without offering any evidence to support them.

When representing the integrator I work for, I for one always try to present the products and services we offer for sale as truthfully as possible. Of course we promote what we believe to be their attractive features to customers, but we also answer customers' questions as truthfully as we can, including discussion of known issues and unknown factors (the two obvious ones in the context of this discussion being whether the light sources will last through the number of hours manufacturers claim, and if claims made in some manufacturers' promotional material about these projectors needing zero or near zero maintenance are actually true). It is not in our interest to mislead a potential customer in order to secure a quick sale of, for the customer, a major capital investment: this industry is small enough that doing so would be remembered and become widespread knowledge, and would very quickly impact our long-term reputation.

In any case, for anyone contemplating the purchase of a new DCI projector, the question of xenon vs. laser is now almost academic. Barco and SharpNEC no longer offer xenon projectors for sale. Christie still has them, but I suspect not for much longer. I'd have to go through my records, but I don't think I've installed a new lamp projector (excluding a few NC1000s in residence theaters) since before the pandemic. The only ones I have installed post-pandemic are refurbished ones that we've bought from customers upgrading to laser, and then usually sold on to the owners of failing Series 1 or very early Series 2 machines who don't have the budget to replace them with new. We get one or two post house screenings rooms or residence theaters specifically wanting xenon and not wanting laser, but no regular movie theaters that I'm aware of.

[Miguel Moreno]

This is what I always ask of manufacturers when we have meetings where they offer us laser equipment. A real comparison of the electricity consumption between a projector with a xenon lamp and a laser equipment but they have never been able to share that data with me since, I believe that in terms of image there are not many differences

[Ryan Gallagher]

I had never even thought about the energy consumption in colder climates (being in Texas)... the idea of venting to the return air instead of outside kinda makes those power hunger xenons useful (though one would hope the building heater is more efficient... but pre-warming it's return air rather than just wasting that heat certainly has upsides).