Ammonia Chiller versus ***** Chiller

[Jacek]

Hello Guys!

Could somebody tell me what kind of chiller is better, more efficient? It is said that ammonia is more efficient (and future) refrigerant than *****s... But if we have chillers to compare - which is better? I haven't got selections of both chillers to compare and don't even know which one have better EER (COP)...

Thanks for any replies.

Jacek

[Jacek]

P. S.

Let's compare two chillers with the leaving water temperature of 7 deg. C

[US Iceman]

I think the word efficient is over used today. This simple word is meant to explain all things better or worse.

Ammonia has higher heat transfer coefficients than other common refrigerants. Does that make it more efficient? Perhaps, but the size of the ammonia chiller will be smaller than the R-22 chiller. Same for the condenser.

What happens if we use the same size heat exchangers for both refrigerants and then compare the energy use, ammonia would be better because the approach temperatures would be smaller.

I think it is important to compare the two refrigerants equally to get a factual analogy to the real facts.

[Bart Nabbe]

Hello Iceman,

I think your right but here in Europe we have antother problem.
You mention R-22 but it's not allowed to use that anymore in new installations / chillers. And....from 2010 it's only allowed to use regenerated R-22 for service and from 2015 R-22 is banned completely.

So it has to be antother *****type. But since here in Europe ***** use is getting worse and worse maybe other types (for example R134a) are also banned in the future.

So since Jacek is from Poland i think the best option for them is NH3.
The european union even gives taxcuts when you use natural refrigerants.

Just so you know, didn't want to break down your help becuase you are right.

Greets,

Bart.

[US Iceman]

You mention R-22 but it's not allowed to use that anymore in new installations / chillers. And....from 2010 it's only allowed to use regenerated R-22 for service and from 2015 R-22 is banned completely.

I know, that was just an example. R-22 was the most prevalent refrigerant left over from the past. It was also close to ammonia in performance capabilities.

I'm not trying to recommend other refrigerants. Ammonia is very good to use for a lot of applications. Especially fairly high temperature projects as chillers.

Another aspect of refrigerant use are the local safety codes. If they limit refrigerant use for specific applications, it does not matter how efficient they are.

[Jacek]

Hello Guys.

Thanks for replies.

Could someone make for me comparision between ammonia chiller and R134achiller and provide me with EER and ESEER (equivalent of American IPLV) for both chillers for comparison?

We have conditions as below:
1. Cooling capacity: 1000 kW.
2. Water temperatures: 12/7 deg. C.

I'd like to have these ESEERs for LCC analysis and know which chiller is better in, let's say, 15-year time. Asking for this, I don't think about enviromental aspects - I know that ammonia is the best solution...

Thank you in advance.

Jacek, from Poland

[valterb]

hello Jacek,
here in Italy Nh3 is preferred on medium big size of plant (like yours 1000 kw for example is the starting size).
Infact we have a lot of rules on Nh3 employ on plant from fire dept.
On small plant usually we prefer ***** chiller units.

[TXiceman]

Jacek, if you do not have the vendor softwear to select equipment, your best bet is to contact several vendors to get budget information on various refigerants.

Typicall, the commerical "*****" vendor will not ahve any information for NH3 other than to bad-mouth NH3. Most NH3 equipment vendors can also provide a "*****" system.

Each vendor can provide the ESEER data and whne provided with an energy cost, can provide a life-cycle operating cost.

You will need to be sure all are compared on the same life-cycle, energy cost and cost of money.

At this point you are actually getting into the duties of a consultanting engineer to make an accurate life time cost analysis.

ken

[Jacek]

Jacek, if you do not have the vendor softwear to select equipment, your best bet is to contact several vendors to get budget information on various refigerants.

Typicall, the commerical "*****" vendor will not ahve any information for NH3 other than to bad-mouth NH3. Most NH3 equipment vendors can also provide a "*****" system.

Each vendor can provide the ESEER data and whne provided with an energy cost, can provide a life-cycle operating cost.

You will need to be sure all are compared on the same life-cycle, energy cost and cost of money.

At this point you are actually getting into the duties of a consultanting engineer to make an accurate life time cost analysis.

ken

Could somebody compare for me a NH3 chiller with a ***** chiller? Conditions are:

1. Cooling capacity of 1000 kW.
2. Water temperature: 12/7 deg. C.

Each chiller is of water-cooled type and with (a) screw compressor(s). Probably an ammonia chiller can use only one compressor for such a capacity (more compressors are needed for a ***** chiller).

[TXiceman]

jacek, it would be best if you called your local vendors and did your own work. Contact your local GEA or Grasso rep to get both bases covered. Carrier or Trane will quote ***** only and York/Frick can do both if you get the right office, not the commercial office.

Ken

[Jacek]

jacek, it would be best if you called your local vendors and did your own work. Contact your local GEA or Grasso rep to get both bases covered. Carrier or Trane will quote ***** only and York/Frick can do both if you get the right office, not the commercial office.

Ken

Thank you very much.

Nobody on the forum cannot give me the COPs (or ESEERs or IPLVs) for these two options?

Jacek

[US Iceman]

Nobody on the forum cannot give me the COPs (or ESEERs or IPLVs) for these two options?

I doubt it very much. IPLV's are calculated values to account for part load efficiency and a given set of heat exchangers. Most ammonia chillers I have seen are custom built, not mass produced where it might be worth the effort to perform the IPLV calculations.

The COP's and other calculated ratios or efficiencies can also change depending on how the equipment is selected and operated.

If you lower the condensing temperature, the COP increases. If you raise the evaporating temperature the COP also increases. And on and on...

This is a numbers game. Therefore by changing some assumptions you can get a new set of numbers. It might not be a true representation of what you actually get, but the numbers may look better.

[TXiceman]

IPLV and like numbers are pretty much specific to standard off the shelf design type units. You can do them for custom units which ammonia units fall into, can be done, but it is alot of work. I have done the calculations, and it is very time consuming.

This is why I suggested you go back to the vendors and let them earn their commissions.

Like Mike said...it is a numbers game and I think it has no real use for a custom unit or an ammonia unit.

Ken

[hladotech]

Jacek, here you are:
Ammonia COP Sabroe PAC 163HF-A 1041Kw/200kW=5.2 (water cooled 25/30)
McQuay 134a, PFS-B 296.2 1060kW/158kW=6.7 (water cooled 25/30)

The difference in chiller design. This is the main point. I've compared the serial models.

[TXiceman]

Haldotech, the numbers apply only to the specific units you selected and can be changed by designing with larger or smaller heat exchangers.

By redesigning, you can make the units swap places.

Ken

[hladotech]

Haldotech, the numbers apply only to the specific units you selected and can be changed by designing with larger or smaller heat exchangers.

By redesigning, you can make the units swap places.

Ken

Ken, as you know, different from serial design - different money. Of course, at equal chiller design ammonia is better.
But I think Jacek asked exactly what I've answered.

[taz24]

Ken, as you know, different from serial design - different money. Of course, at equal chiller design ammonia is better.
But I think Jacek asked exactly what I've answered.

But he asked 2 years ago and has not been back to this thread.......



taz



.

[hladotech]

Nevertheless...

[Jacek]

Many thanks hladotech.

Best regards,

Jacek

Jacek, here you are:
Ammonia COP Sabroe PAC 163HF-A 1041Kw/200kW=5.2 (water cooled 25/30)
McQuay 134a, PFS-B 296.2 1060kW/158kW=6.7 (water cooled 25/30)

The difference in chiller design. This is the main point. I've compared the serial models.