PDA

View Full Version : Energy saving







chemi-cool
15-11-2006, 06:48 PM
Hi guys,


Looks like the next big thing around the globe, is energy saving.

it can be employed in every electricity consuming kind of motor.

So, dig the www, ask around, invent, but come with new things and ideas.

Chemi:)

Brian_UK
15-11-2006, 06:50 PM
OK, I'll start.

How about water cooled electric motors, the rejected heat being used to pre-heat other services.

Brian_UK
15-11-2006, 07:18 PM
Interesting thoughts here...
Using the correct size power cables etc
http://www.cda.org.uk/megab2/elecapps/pub116/index.htm
also
items 172, 173 and 176
http://www.cda.org.uk/frontend/pubs.htm

US Iceman
15-11-2006, 08:06 PM
I think there is a lot we can do by selecting the equipment correctly.

For instance... On open drive equipment (compressors, fans, pumps) the highest motor efficiency is obtained at approximately 75% of the full load power.

For example, a 100 kW motor has a higher efficiency when it is only loaded to ouput 75 kW. Doing this provides four benefits;

A higher efficiency
The motor runs cooler, since it is not at it's maximum rating (neglecting the service factor of course)
You now have a safety factor of approx. 25% for pull down loads, etc.
The motor starter and wires are not fully loaded either.Most water pumps/motors are commonly oversized to allow for "things gone wrong" or missed in the design. This results in oversized motors and pumps that waste energy.

And my big pet peeve, don't use air-cooled condensers unless you absolutely have to!

This should prove to be a fun topic, so my hats off to Chemi for starting this.:cool:

old gas bottle
15-11-2006, 08:17 PM
errrrrrrrrrrr whats up with air cooled condensers ice man??

LRAC
15-11-2006, 08:28 PM
Hi chemi-cool

when stating energy saving are you talking about the cost to the end user for the elctricity or on a environmental issue as they both differ greatly.

We run our diesel site generators for contract work on wait for it old chip fat oil NO Cost to us and plenty of old oil about and its vegatable oil so hey possibly environmentally friendly as well.

OK we've blown up 1 generator but it lasted 4 years which ain't bad( we forgot to change the filter and fish batter etc completely naffed it).

regards
Lrac

p.s you need to know a few chip shops or restaurants.

US Iceman
15-11-2006, 09:05 PM
Hi,



errrrrrrrrrrr whats up with air cooled condensers ice man??


OK, I'll try to explain my view of these. An air-cooled condenser is dependent on the dry bulb temperature of the air to provide the cooling for the condenser. This causes some issues, because the maximum cooling is required during the hottest times (summer typically).

When you add the dry bulb temperature to the design TD of the air-cooled condenser, the condensing temperatures can be quite high.

As a result of the higher condensing temperatures/discharge pressures the compressors have to work harder, which requires more energy input.

Due to the large volumes of air required to remove the heat during the condensing process, the fan motors typically require large power inputs too.

Using the wet bulb temperature (water towers or evaporative condensers) allows the condensing temperature to be operated much lower than when air-cooled condensers are used.

Hence, the tower or evap. condensers also have to move much less air volumes, than an air-cooled condenser.

This may not be acceptable in all applications, but I think it is certainly worth a look. I can remember when almost everything was water-cooled of some sort.

Good Lord, I just dated myself!:o

Andy
15-11-2006, 09:11 PM
Hi guys,


Looks like the next big thing around the globe, is energy saving.

it can be employed in every electricity consuming kind of motor.

So, dig the www, ask around, invent, but come with new things and ideas.

Chemi:)

Chemi:)
inventing energy saving systems for refrigeration has been 50% of my job for the last two years:)
We have a very good heat recovery system:)
We fit inverters on our lead compressor on every supermarket pack:)
We fit the best that Danfoss has to offer in controls and electronic expansion valves:)
I have also just invented a floating head technology that works in combination with heat recovery:eek:
a very simple idea that we are aplying for patent on:)

So if you as me I think energy is the future:D

Kind Regards Andy:)

LRAC
16-11-2006, 08:06 AM
I have also just invented a floating head technology that works in combination with heat recovery:eek:
a very simple idea that we are aplying for patent on:)

Hi Andy

I thought this has already been done by hy/save how does your's differ.

www.fridgetech.com/hysave%5flds/ (http://www.fridgetech.com/hysave%5flds/)

Kind regards
Lrac

old gas bottle
16-11-2006, 09:04 AM
hi iceman,well thats a good viewpoint and expected nothing less, i tend to like aircooled better because a lot of the water induced systems i have come accross are poorley maintained and very troublesome, if the aircooled units are sized on the generous side with a good capacity control i think there a better future option for reason two, water over here will become a bigger issue than power, were allready metered up and the heavy usage in the overhall life of a system may prove to much,but thats just my opinion,

i too had a brain wave a while ago ! condenser fan motors that are powered by the discharge pressure, a motor that has a impeller in a sealed case that the variable head pessure would hopefully turn it at the desired speed required, the shaft seal would have to be good but i think it could work,what do you think ? dont forget you heard it first here, ha ha.

US Iceman
16-11-2006, 04:23 PM
Hi OGB,



...because a lot of the water induced systems i have come accross are poorley maintained and very troublesome...


That's very true. A lot of the older systems I have seen were in very poor condition due to a lack of maintenance. And, when these did get serviced it was a horrendous job to rod and clean out the condenser tubes and clean the junk out of the towers (if one was used at all, some were only using city water or well water).

I remember a story my grandfather told one time about air-cooled condensers. When they were first starting to be used, he installed one as a replacement for a water cooled system. He did exactly as you suggest and oversized.

These are not without maintenance issues too. Trying to clean an air-cooled condenser well, can be a day long job.

The next best thing is trying to straighten the fins where "someone" has folded them over. I've seen footprints imbedded in large air-cooled condenser fins. That was fun to fix.:mad:




i too had a brain wave a while ago ! condenser fan motors that are powered by the discharge pressure, a motor that has a impeller in a sealed case that the variable head pessure would hopefully turn it at the desired speed required, the shaft seal would have to be good but i think it could work,what do you think ? dont forget you heard it first here, ha ha.


That sounds like a regenerative turbine pump used in very large water systems. They use the falling return water to power the pump.

I like the thought. Wild ideas based on good principles sometimes turn into money!

chemi-cool
16-11-2006, 05:07 PM
So far, so good:)

Andy, yes, I spend a lot of time thinking about it.
As US Icman said, large air cooled condensers with frequency controlled fans [ by head pressure] are fantastic.

LRAC, I install many Hy save pumps, they are much better in cold ambient where head pressure is too low.

At the moment, I install them on a Carrier water chiller and will post some photos when its done.

Keep posting your thoughts, we will get to some interesting ideas.

Chemi:)

Andy
16-11-2006, 10:24 PM
Hi Andy

I thought this has already been done by hy/save how does your's differ.

www.fridgetech.com/hysave%5flds/ (http://www.fridgetech.com/hysave%5flds/)

Kind regards
Lrac

Hi LRAC:)

If I told you that you would could copy me:D

On heat recovery we condense in the heat recovery condenser and use the condenser as a subcooler, with the head pressure elevated to 45 deg c to get the heat out, making up the addtional energy used at the high head by highly subcooling the liquid. We have now added a bit of control that allows the head pressure to float using the surface area of both condensers without the head pressure elevated (under certain conditions)

Kind Regards Andy:)

Josip
16-11-2006, 11:03 PM
Hi, all :)

What about to reduce *****s and use ammonia much more;)

Best regards, Josip :)

US Iceman
16-11-2006, 11:12 PM
...use ammonia much more;)


Oooh, I like that idea.:D

That comes with built-in job protection as everyone thinks it is too dangerous.:rolleyes: It is of course, if you don't know what you are supposed to be doing.

Handyman-1
17-11-2006, 12:39 AM
Hi guys,


Looks like the next big thing around the globe, is energy saving.

it can be employed in every electricity consuming kind of motor.

Chemi:)

Dear Chemi,

In developing country like ours, whatever the bill the utility firm gives to end users is treated as CORRECT & the RIGHT one.

I have this customer that was billed almost double (a little less US$4,000/month to almost US$7,000)than what he needs to pay. He hired a lawyer and demand that it must be corrected.
The utility firm instead cut his electrical power supply line and my customer has to run his generating set (500KVA). It is more expensive then than just paying the utility firm.

So, my customer have no choice but to pay a fine/back billing (approx US$20,000) or else . . .NO POWER . . :mad: :o :(

Can you possibly, lead me to a site that will help me find a hardware/software that will record all electrical consumption. This can then be used in a next court battle my customer plans to make. . . ;)

Thank you in advance & hope i can find a way to help my customer.

Kind Regards too.

US Iceman
17-11-2006, 01:57 AM
Hi Handyman-1,

Take a look at this link.
http://www.dranetz-bmi.com/applications/appspec.cfm?appscat=1&apps=52

The entire website is devoted to similar applications and needs as the one you describe.

These devices are capable of what you are asking for and are able to record the exact energy, demand, etc. with I believe very good accuracy.

Setup the recorder and let it run. Now you have exact use, time of day, etc.

I would recommend your customer get a copy of the rate structure for his facility that shows how he is supposed to be billed for his energy use. These are sometimes very complex and hard to understand.

My understanding is these devices are not cheap, but then again, his power costs are not either.

I hope that helps.

US Iceman

Abby Normal
17-11-2006, 04:10 PM
Try and use the energy twice. Heat of rejection makes domestic hot water, or the hot gas reheats the air needed for humidity control.

Supermarkets in the western side of the Atlantic, reclaim a lot of heat from racks to warm the ventilation air and even heat the stores until it gets well sub-zero out.

Build buildings that are energy functional and not the ones that look pretty.

Find a room temperature superconductor, to reduce the heat load of servers.