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US Iceman
07-09-2005, 05:40 PM
The recent issue of Scientific American (September, 2005) is a special issue focusing on the planetary future. This is a very fascinating set of articles.

The first inside page starts off with an advertisement from Chevron.


It took us 125 years to use the first trillion barrels of oil. We'll use the next trillion in 30. So why should we care?

Pretty scary information.:eek:

There is an article in this issue titled "More Profit With Less Carbon" by Amory B. Lovins. I would highly recommend this for your review.

One point he makes in the article deals with losses in electricity generation. His example is for a power plant. The example states, if we consider the fuel energy input into the generating plant as 100 units, with the final output for pumping water, the net available output is 10 units. A 90% loss due to the system design and inefficiencies in power transmission and ultimate use.

The equivalent useful energy is only 10% of what it took to deliver this result. The author goes on to state, if the piping friction losses where reduced 1 unit of energy (with a larger pipe or better design), the initial input energy is reduced by 10 units. A significant increase.

You might be asking what in the world does this have to do with refrigeration?:confused:

My thoughts follow for two areas: package equipment and custom engineered systems.

Refrigeration systems are a large user of electricity. In this category I would include large central HVAC systems.

The packaged equipment from a manufacturer is pre-designed for a specific purpose and based on certain requirements. Some of these requirements are mandated by governmental legislation for energy conservation. You can only get what the manufacturer supplies. Large HVAC chilled & hot water piping systems are some areas for improvements.

Installation and commissioning are the two primary items under our control. A poor installation or bad commissioning practices can leave well designed system operating badly and inefficiently. We should be able to do something about this.

Custom engineered systems on the other hand add another level of complexity. In this situation, we need to not only design the system, but perform the installation properly and provide good commissioning principles.

An example, if the suction lines are sized too small to save some money (more competitive?) the compressors may become larger due to the loss of capacity associated with increased pressure losses.

Improper piping practices on liquid lines can contribute to increased flash gas and a subsequent loss of capacity. This can result in increased run-time for the system, or loss of temperature control.

The use of an unnecessary quantity of valves and pipe fittings compounds the pressure losses. You have probably seen this before on a new installation. The duct work is run first, then the electrical conduits and water plumbing. Who is usually the last person?

The refrigeration pipe-fitter. :( He has to run piping around all of the other obstructions. We can minimize this by requesting first choice of the installation.

What I am proposing is a whole system approach to engineering these systems. Some of this is applicable to your proposals. The owner is concerned with total costs. If the proposals are evaluated on your cost versus your competitor, the low cost usually wins.

Can you sell the whole system approach to the owner. Less cost for the electrician or plumber leaves more for you! How can you optimize your design for the proposal?

Less electrical input for the refrigeration system can reduce the wiring costs for the owner. Can you use the difference in the costs to sell your systems by designing them to be more efficient?

Can we design defrost systems that are more efficient? The short answer is YES. Do we need dozens of pressure regulators to do this. NO! Is electric defrost really cheaper to install. I don't think so.

Why can't we design systems that operate at 10C condensing in the winter time? We can, if we get creative. Can we get lower than this, I think so but it depends on what the process requires.

Heat recovery in HVAC systems. Heat pipes, or thermosiphon systems can be used. Do you need heat energy or temperature? These are different things.

I believe we are at a cross-roads. We either start taking the energy business serious and see how we can profit from it, or succumb to it.

What do you think about this?

botrous
07-09-2005, 08:30 PM
Hi US Iceman , I think this concerns every body involved in energy from petrol companies to the end users . . .
The only way to do this in a right way is to expand the end users sens or responsability vers the energy resources . . . to expand their culture on such subjects then they will be more than happy to contribute in saving our energy resources and the planet.

Last year I designed hot water system for a large building , I decided to use solar water heaters , the coast was high comparing it to electrical or petrol water heaters , but as i explained to the customer that he will be saving a lot on electricity and petrol bills and how he was contributing in the planet saving , he thought for a while than accepted ...
We installed the solar water heaters , and now the customer is very happy with the lowwwwwww and i mean lowwwwww coast of the hot water ....

Immagine a full facility that uses , solar water heaters , passive architecture for cooling and heating (which can improve the efficiency and the coast of an active cooling/heating system),the heating systems uses geothermal heat pumps to heat the building, where the rubbish and the trash of the building are being used for gas production for heating and cooking , and where a part from the electricity is produced using PV panels. It costs a lot , but it saves a LOT LOT in 5 years , as a matter of fact it pays for it self in 5 to 10 years , which is a long term investment but a winner one.

For the interrested in the renewable energy , you can visit www.homepower.com to read some articles about the power of the renewable energy which is the futur.

Best regards

frank
07-09-2005, 08:37 PM
He has to run piping around all of the other obstructions. We can minimize this by requesting first choice of the installation.

If you do request this and get a positive result please let us know :D - I've NEVER been on a site where anything we say makes the slightest bit of difference to the "mind set" of the site manager.

I've got to agree with most of the points you raise though. I do see an awful lot of energy wasted - especially as most owners only call you in when it goes tits up. Just regular cleaning of filters on AC allows the systems to operate with better efficiency but try telling the owners - it's like knocking your head against a brick wall. All they see are ££'s signs.

botrous
07-09-2005, 08:45 PM
those are direct links to passive cooling basics
http://www.homepower.com/files/hp82pg84.pdf
http://www.homepower.com/files/hp83pg66.pdf

cheers :)

US Iceman
07-09-2005, 10:20 PM
Hi Frank,

I agree with you on the site managers outlook. Most of them could give a rats behind with what we want. They only care about schedules and cost overruns.

Somehow we as an industry have to find a way to make this important, and better yet, how do we get the owner to enforce this.

I have asked for first shot at the space for piping. If I have a good relationship with the owner I used to win fairly often.

Consulting engineers can accommodate this when they do the drawings if they are specifying the piping runs. Unfortunately, the biggest stuff usually wins. Chilled water piping and duct work, that sort of thing.

It is sort of a compound problem, or similar to the chicken and the egg problem. Which one comes first?

I also agree with the maintenance predicament you describe. The owners only understand money. They don't know anything about what we do or why. Only that we cost money!:D

One of the more difficult points to teach an owner is the difference between predictive maintenance and preventative maintenance.

They tend to think in terms of immediate costs since this is what they see and have to write checks for. You are right, it is like a brick wall. I'm trying to figure out a way that we can overcome this mindset and work it to our advantage.

I hope to get some discussion on this from everyones view and see if there are any ideas.

By the way, I liked your anatomical reference. I've used this before, and just barely caught myself before saying it in "mixed" company.:eek: Not good:(

US Iceman
07-09-2005, 10:33 PM
Hi Botrous,

You mentioned solar panels. There used to be a company that used solar panels with refrigerant flowing through the panels. The panels were the evaporator to a mechanical refrigeration system. In other words, a solar powered heat pump.

I thought this was pretty cool. I don't know if the company is still in business (I can't remember the name, but will try to look for information).

I believe they used a low pressure refrigerant like R-12 or R-114 )which we cannot use now.

I mention this as another idea on how to solve a problem.

Sorry for the time lag in replying. I got stuck on a long conference call.:(

Best Regards

US Iceman
08-09-2005, 12:06 AM
Hi Botrous

Here is the link for the solar panels and other solar related information.

http://www.vip-page.net/solarresearch/

I have not received the information yet. I want to see what they have done different in the last 20 years or so.

I hope this is of interest to you.

Regards,

botrous
08-09-2005, 01:17 PM
Thanks Us Iceman for the link , i will check it later tonight .
At the university we tried to design and manufacture a refrigerator using ammonia and the solar heat as source of heating the ammonia (sure at night time , it will use energy stocked during the day ) but the project was aborted due to financial reasons :mad:
Best regards

US Iceman
08-09-2005, 02:45 PM
Here is a link that describes some of the problems in selling energy conservation. This short article provides some information and tips on presenting the facts and how to put the proposal in a context that the owner can understand.

http://www.facilitiesnet.com/bom/article.asp?id=2019

I believe this helps to show us one more way where we as refrigeration engineers can make a difference.

We understand the common language of refrigeration systems, so we have to put this into a format that means something to the person with the money.

frank
08-09-2005, 07:35 PM
By the way, I liked your anatomical reference. I've used this before, and just barely caught myself before saying it in "mixed" company. Not good

Hi Iceman

I thought that all you Americans said what you like. :D

last time I was in New York I heard " I pay my taxes so I'll say what I like". Nice mindset :p

US Iceman
08-09-2005, 10:21 PM
Hi Frank,

There is an old medical problem known as foot & mouth disease.:D Sometimes I catch myself, sometimes I don't. This is why I stay out of politics. I'm too tempted to tell someone what they can do, or put what... where?

I'm not sure if there is a cure other than restraint!:rolleyes:

I've heard what you were describing too. A lot of people confuse free-speech with saying anything they want, and not caring who heard it. These are typically emotional outbursts with no discernable thought given to the comments or audience.

Unfortunately, some people tend to lead with their mouth
and it gives all of us a bad name. Not too different from a spoiled child:o

Some people do not make good ambassadors for us!

I got a good laugh from your comments.

Thanks,
US Iceman

marchse
09-07-2010, 06:21 AM
The only solution is all the people should have the responsibility to save the energy and conserve it...

sachin230
09-07-2010, 07:52 AM
Find here ,energy conservation tips

http://www.mahaurja.com/EC_Introduction.html

Segei
09-07-2010, 10:43 PM
The only solution is all the people should have the responsibility to save the energy and conserve it...
This is good statement. Only one question. How?

marchse
10-07-2010, 07:55 AM
unnecessary usage of electricity in your house and industries, this itself will be a good start.

Segei
10-07-2010, 09:44 PM
unnecessary usage of electricity in your house and industries, this itself will be a good start.
In energy conservation every next step is harder and harder. It is easy to shut the light off. What else?

Grizzly
10-07-2010, 10:25 PM
Someone Has been saving a lot of Energy.
This post is 5 yrs old!
Grizzly

Segei
10-07-2010, 10:42 PM
Someone Has been saving a lot of Energy.
This post is 5 yrs old!
Grizzly
And we still don't know how to save energy( except shut the light off). Probably, it is not so easy.:)

Tesla
11-07-2010, 09:10 AM
HI
Five years on and it's now an even bigger topic, but. Excuse me for disagreeing with part - I think green house gas and global warming is political propaganda. I totally agree with saving energy (or not wasting it) and I am doing something about it. I am working for a company which saves 10% - 15% of power consumption of commercial buildings by optimising the control of BMS, with CSIRO research (15 man years). with computers and software we can measure and analyse automatically make adjustments etc.

Segei
12-07-2010, 02:18 AM
I agree that energy conservation is complicated issue.

magy
20-07-2010, 10:52 AM
this is quite an intricate matter