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Hartman Loop/Optimum Energy Controls

Hartman Loop/Optimum Energy Controls

Hartman Loop/Optimum Energy Controls

(OP)
I have been approached about adding control software from Optimum Energy into a project I am working on and was wondering if anyone has any information, thoughts, opinions, etc.  

The energy savings they advertise seem to be very optimistic.  Adding the system would increase the first cost substantially but they are suggesting it will result in a 40% rate of return and a 50% reduction in plant energy costs.  I don't doubt that having a system comprised of well matched all variable speed equipment controlled "perfectly" would result in lower energy costs - of course it would but it this system that perfect and could it really cut the energy costs in half?  I don't buy it.  

I am not experienced with retrofits and this wouldn't be a retrofit either, so whatever improvement is actually realised I would never know.  If this system really cuts energy costs in half and does so with a 40% rate of return, then the choice is a no brainer but does it?  Does it even come close?     

RE: Hartman Loop/Optimum Energy Controls

The old adage that "if something seems too good to be true, then it probably is", really seems to apply here.  That level of savings just seem to be an outrageous claim.  And to put that cost on an initial investment that could never be quantified is perfect for these miracle solutions.

The results can never be verified.  I would insist on a long list of installed systems complete with owner references that you can contact and documentation of existing and post-installation energy consumption profiles before I even consider putting them on the project.

These numbers just aren't optimistic, I doubt they are anywhere close to realistic.  I would take this information with several million grains of salt.  Their website quotes 30% to 60% electrical energy savings for some systems.  With just a software addition? (And of course VFD's on everything in your system if they are not already part of the system-although I bet those costs aren't part of any economic analysis they do).

It would be interesting to follow up to see if they offer any project references.  My money would be against them havings such.

Good luck and keep us informed.

EEJaime

RE: Hartman Loop/Optimum Energy Controls

I've also seen this presentation, and the case studies look pretty convincing.  They apparantly bought up all the Hartman patents, and license it back to Hartman for up to 10 installations a year.

This is a packaged software version of the hartman loop which only works on all variable speed plant.  You have to have the plant to go with the technology.  They install a tridium based box to take over the system control, spend a week commissioning and let it go.

I'd like to hear also if anyone out there has installed one of these and what the results were.

RE: Hartman Loop/Optimum Energy Controls

(OP)
Well I don't know if I would be convinced of 50% without installing it myself on a plant and seeing it with my own eyes.  

I know if I owned the rights to a product that gave a 50% savings in energy costs, I wouldn't sell it for a price that would allow a 40% rate of return.  Why not limit your business exclusively to performance contracts and make a killing?   

RE: Hartman Loop/Optimum Energy Controls

Yeah, the "why not get rich on a performance contract" was the first thing that I thought of too.

The web site doesn't have any of the obvious snake oil signals.

RE: Hartman Loop/Optimum Energy Controls

(OP)
No it doesn't and the concept makes sense, but I can't think of a good way to get my head around the amount of savings that could be expected.  I read an article today from the September 2001 issue of the ASHRAE Journal by Tom Hartman titled "All-Variable Speed Centrifugal Chiller Plants" (4 years prior to Optimum Energy forming) and it basically tells how and why a setup like this would work and mentions a study of 15 buildings in different climates that showed an average savings of 28%.  Between the last couple days spent reading and thinking I can't come up with much of an arguement against their claims other than that they sound too good to be true.  If anyone else has any thoughts to offer I'd be glad to hear them.

RE: Hartman Loop/Optimum Energy Controls

I haven't read closely enough.  Do they claim up to 50% energy savings, or energy cost savings?

I could see some nice reductions in demand charges with the right (wrong?) utility rate structure.

RE: Hartman Loop/Optimum Energy Controls

I have done quite a bit of research on the Optimum Energy guys and I have to say I am very impressed.  

They can save 50% of the energy cost in plants that have bad controls, bad operators, or improperly sized equipment.

On a new plant the NPV is tougher to justify, since you don't really know what the play is going to do in the real world.

If you have a wide varying load profile, I would seriously consider them.  We didn't end up buying there software because we had a pretty constant load profile, however I was pretty impressed.

Zuccus



 

RE: Hartman Loop/Optimum Energy Controls

Having worked as a controls programmer with Trane for many years, I , too , was skeptical of the savings claims made by Optimum Energy. Their Director of Engineering convinced me by giving tours of central plants with their software installed, studying the baseline measurement process and data, and speaking with the engineers that 1) monitor the utility bills and 2) operate the plant.  I was so convinced that I work for Optimum Energy now.

Kevin, I work in Texas, but I'm sure whoever you're working with will provide references, case studies and a more thorough review with our Director of Engineering, Ben Erpelding, to address your concerns.

With new consruction, we usually use the Savings by Design calculations (without using the Optimum Energy software) as the baseline and then compare the actual consumption to determine savings (kWh and $$).

As for the "getting rich doing Performance Contracting" issue: Optimum Energy is very clearly positioned as a software solution. With so many buildings in the U.S. with centrifugal chillers, why limit this technology to a handful of projects that operate under performance contracts?

To address the comment about VFDs and whether they are included in Optimum Energy's economic analysis...in fact our initial savings analysis does include the entire project costs (estimates for work outside of our scope, controls programming, equipment upgrades, engineering if needed, 30% markup, taxes and contingency). No miracles here...just sound engineering that is swiftly commissioned and measured and verified for a minumum of 1 year after installaton.

RE: Hartman Loop/Optimum Energy Controls

(OP)
Thanks,

I'm sure I'll get a chance to look into it further sometime in the future and look forward to it.  Since posting I've talked to some people about the system and actually found that a close acquaintance of mine in San Diego has been in touch with Ben and said good things about the system based on what he knows and has heard.  Still the 60% savings raises my eyebrows and I have to assume savings of that magnitude are based on a poorly managed system, but overall based on discussions I've had I haven't been able to find anyone with anything bad to say (or anyone that swears by it).  But like I said previously, I can't argue against it and the theory behind the Hartman Loop seems solid based on my own understanding.  Being a design engineer and not a facilities guy though makes it difficult to fully appreciate the things going on at that end.  Just thought I would end the thread with that – I have nothing negative to say but would still like to know more.  Any Chicago area installations?  

-Kevin Caho

kevin.caho@gmail.com


 

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