Ice Storage systems Info

[stuckagain]

I am hearing a lot about these systems lately.
I gather they use an R-123 chiller with glycol to,freeze water
In the off peak, and then run chill water through the ice during the day.
Does any one have any type of literature or manuals about this,including setpoints and
What type of capacities you can normally see.
They sent me and a partner to a hospital that is using a Fafco system.
How long on average does it take to freeze the water?What are some of the drawbacks
(problems) one would encounter with this system?I guess I am looking for a good crash course.

[INTECHBILL]

Be a bit more specific and detial with your question - FYI the specific heat of water is 1

[tunaguy]

You can Google thermal storage on the Web or this forum. Generally speaking they're more expensive to install, but some utility companies have issued credits to lower their peak electrical demands. They're typically higher maintenance, more complicated and can be a real pain if they don't make ice the previous night.
It varies on the amount of time to make ice, but it typically takes 6-8 hours. Normally, they need to cool the warm water down first before they can effectively make ice. Research the company that makes the equipment because many companies have come and gone the last 20 years. Check customers that have owned these systems for 5 years or more. Again typically, these systems don't last as long as a conventional system.

[freonrick]

normally the chiller is not sized to handle the load of the building. if something fails and ice is not made then the chiller can't keep up during the peak time. unless a chiller was designed to do so. you can use a chiller to pump glycol into tanks with water that will freeze and have chill water(glycol) go through tubes into the building. you can have a large tank with several plate evaps that will freeze water to a set thickness and that same water is used for chill water. you can also make slush to do the job. I never saw two jobs the same. the biggest draw back is if you have no ice then not enough cooling the next day. I had one about 20 years ago that used 2 compressors, a 400 and a 300 ton compressor. it held 14,000lbs of r22. so the expense can be high to install and maintain. but I have not compared numbers to be sure on that either.

[jayguy]

there are several theories of operation...

1. chillers are sized to make ice only at night
Good: smaller chillers = lower first cost and lower energy bills as night time is usually cooler
Bad: no ability (or little ability) to catch up during the day if there is a problem during the night, higher cost per kWh if run during the day

2. chillers are sized to make ice at night AND can handle the load during the day
Good: redundancy
Bad: higher first cost, over sized during normal operation, higher cost per kWh if run during the day

3. chillers are sized "middle of the road"
Good: chillers "help" handle the load at the highest load times, ice will handle it most of the time, cost per kWh during the day is not as damaging as the other 2 choices
Bad: Middle of the road costs, not as much help from the utility to pay for the installation


which is best for you will depend on what is important to you (and the specifying engineer). as for option #3, the "middle of the road" could be anywhere from 10% to 90% of the load so that could really be anywhere.

and any refrigerant could be used...some will have a better kWh/ton rating depending on tonnage and manufacturer.

[flange]

as stated above, there are many variables. short story, ice is produced at night during off peak electric rate, and used to either supplement or provide the chilled water for cooling during the day. payback is typically prety good in metropolitian areas due to high rates and ratchet.

[referteacher]

a dead snake is hard to find with a thermal imager.????????????

Hey, JayGuy. I thought snakes were "cold-blooded". So wouldn't a live one be just as hard to find with a thermal imager???

[jayguy]

a dead snake is hard to find with a thermal imager.????????????

Hey, JayGuy. I thought snakes were "cold-blooded". So wouldn't a live one be just as hard to find with a thermal imager???

Hee Hee!! I found a water leak behind a wall this weekend...the drywall was as hard and dry as could be. big water bubble in the ceiling so i imaged the room and there was a big leak behind the wall plain as day! found the leak from the outside of the house...pretty cool stuff!

[Anil_zx3]

anyone have information on company's that sell small commercial thermal storage air conditioners. I'm thinking around 3-6 tons. seems like most thermal storage systems cater to large applications rather than residential and small commercial.

i'm in toronto

[icemeister]

anyone have information on company's that sell small commercial thermal storage air conditioners. I'm thinking around 3-6 tons. seems like most thermal storage systems cater to large applications rather than residential and small commercial.

i'm in toronto

Here's one: Ice Bear (http://www.ice-energy.com/technology/icebear/overview.html)

[Anil_zx3]

Here's one: Ice Bear (http://www.ice-energy.com/technology/icebear/overview.html)

i called them but they only sell to the utility. so far they don't have any products available for small commercial applications.

they want the utility to own their units. sorta like national home service and their water heaters i'm guessing. or before direct energy was created when the gas supplier owned the rental tanks.

[stanbyyourword]

awesome :patriot:

[allank]

Instead of calling it a chiller would you not call it a refrigeration unit, like as in an ice bank

[waylansmithers]

I have an ice field at the college I work for. The benefits are that you can make ice at night during off peak times when the electric usage is charged at a lower rate. It is also an advantage to make ice at night when the outside air is lower which makes running your chillers cheaper so you dont need to run them in the high heat. You can also reduce your chiller size to cool more areas.

[ga1279]

Calmac has made them for Trane for years. Yes, they are cheaper to operate because of the reasons stated, but no one mentioned the cost IF you had to operate the same chiller during a peak demand period. 1) You will have a severe penalty imposed on billing as well as an over charge at a rate much higher than a normal rate. 2) Your system has to be either converted to a glycol system in total or a primary/secondary loop has to be established with a heat exchanger and controls for the individual loops. I have seen many of these systems in south Texas and many of them have been in service for 10-15 years with minimal problems. They had payed for themselves within 6 years of operation, even though engineers (sales that is) had predicted a much quicker payback to the customer. Here again it's all in how these systems are maintained.-GEO

[waylansmithers]

We have about 8 large storage tanks burried in an what they call an ice feild, the chillers make ice and store the ice in the feild, then glycol is pumped through a heat exchanger in these tanks. You definately need to use glycol.