Large (5 MBtuh+ ) heat pump application

[seasar]

Is anyone aware of large scale (5 million btus/hr +) heat pumps in the US? The application in question is heating of hot water with a fairly consistent year round demand.
Gas prices in my area have doubled in the last few years and we are forecasting 20% higher ($10 / DTH) in the next year whereas electricity has been cheap and plentiful ($.037/kwhr).

On paper it appears valid (COP of 3, NH3).

 

[Jabba007]

I think you're asking about a water source heat pump? or reverse cycle chiller? Trane has them, as does Milti-Stack. Those are two options that I am aware of.

Jabba

 

[seasar]

Either.

Water source is possible given incoming water temperatures but most water is heated which would offset or completely negate the benefit.

 

[Jabba007]

How hot does the water need to be?

The Multi-Stack chiller guys in my area are beating the bushes like crazy touting the benefits of the energy recovery chillers, and pitch them as first stage heat in a situation where you can ground couple them. I think that the LWT on them is limited to about 125F though I am not SURE of that number.

Jabba

 

[marcoh]

I have seen a project where an air cooled McQuay chiller was used as a heat pump to provide domestic hot water.

 

[mauricestoker]

Are you interested in hot water generation only, or reducing natural gas loading?

I think Ft Gordon, GA (or it might be Stewart) has a large closed loop system-the DOE FEMP site has a story on it.

I'm looking into the same thing for the same conditions. Looking into feasibility of domestic hot water generation during summer to reduce summer boiler load for DHW by zoning geoexchange heap pumps on a secondary loop. Generating DHW would make a good heat sink.

Mostly have air side economizers, so the chiller plant doesn't run when its cold out. Still, with a year round watr source of 55-60 F and a high COP, I'm expecting the life cycle cost to pay off.

 

[seasar]

Both. We have the need for the hot water generation and the savings is realized in reduced natural gas expenditures.

I've spoken with a compressor MFR and this looks very feasible. Much better COP than I was expecting.

 

[KiwiMace]

I have seen McQuay water cooled heat pump, using the plant condenser water as a heat source. Double benefit.

 

[KiwiMace]

This is what I was thinking of:

http://www.mcquay.com/mcquaybiz/literature/lit_ch_wc/Catalogs/PM_Templifier.pdf