Generators Rated for Hot Climates?

[Dilkris]

Not been on for a bit as for many reasons I've ended up in Mali, (we all make mistakes....), Anyway, I'm sure this post is in the wrong section but I just know that someone out there has the answer to my query. (From experience I have found this to be the most informative Forum out there.. )

We are running 2 off 650 Kva Gen Sets on site which originally I am told came from a previous application at a hospital in Paris - ambient temperatures in Mali are presently reaching 45 degrees and I am having difficulty keeping the engines cool; (I have installed water spray bars between the radiator fans and radiators to assist cooling, which although may be technically frowned down upon, is helping.)

So my question is, "Do Generators come configured for the climate they are due to operate in, (bigger radiators for hotter climates say), or are they configured capable of running in all climates.?

 

[Brad93]

Not been on for a bit as for many reasons I've ended up in Mali, (we all make mistakes....), Anyway, I'm sure this post is in the wrong section but I just know that someone out there has the answer to my query. (From experience I have found this to be the most informative Forum out there.. )

We are running 2 off 650 Kva Gen Sets on site which originally I am told came from a previous application at a hospital in Paris - ambient temperatures in Mali are presently reaching 45 degrees and I am having difficulty keeping the engines cool; (I have installed water spray bars between the radiator fans and radiators to assist cooling, which although may be technically frowned down upon, is helping.)

So my question is, "Do Generators come configured for the climate they are due to operate in, (bigger radiators for hotter climates say), or are they configured capable of running in all climates.?

Yeah, air cooled ones which have all been exported to Africa

 

[Dilkris]

Sorry Brad - don't understand - are you saying all generators destined for Africa are generally air cooled?

 

[tigdlo]

Is the genset manufacturer still in business?

What are you doing un Mali other than spraying water on gensets?

 

[Dilkris]

Yes - I believe so - ITM (French) - Leroy-Somer alternators, Engines V8, can't remember the make, but for me they are unusual.
I know what you're going to say - contact ITM......

 

[Dilkris]

What are you doing un Mali other than spraying water on gensets?

Sorry - forgot this bit - "living the dream" and growing old fast.

 

[addjunkie]

They often spec different oils and coolants due to temperature variations.

Also if there older exported machines to Africa the radiator and or cooling system perhaps needs a good back flush or clean out with some magic chemical flush.

Are they in direct sun light or in a container…..shade helps unless your under a geet big flare then your stuffed

 

[Agroshield]

Are you using antifreeze in them? This helps with cooling as well as in cold weather. Is the coolant system properly pressurised? Have you checked coolant pressure when running? I believe radiator caps keep in circa. 15 psi. That lowers the boiling point of the mixture. When was the system last drained and flushed? If your passages are gunked up, that won't help.

Do they have temperature gauges? What are they reading? Have you verified that they are reading correctly? What power are you pulling out of them? I believe you are supposed to derate them for hot climate operation. Do they have an oil cooler? Every little helps. Intercooler on the turbot in good condition? Are they out in the open, under a shade or in an enclosure? A straw roof that you spray (mist) with water will create a cooler micro-climate under it.

ITM seem to be here: https://www.groupes-electrogenes.eu/

There are waterless coolants available, but getting hold of them where you are might be difficult. Depending on what resources you have available, maybe add a heat exchanger to the system (but it would need to withstand the pressure and have lots of surface area). Could be as simple as a big zig-zag of steel pipe in a swimming pool.

 

[RWD3M]

That raises the boiling point of the mixture.

FTFY!

 

[addjunkie]

Are you cleaning the air coolers with ACC9 or what ever it is these days. High air inlet temps will have the machine working harder to deliver the demand.

 

[stevethegrease]

I used to work for a company who made BIG generators, like 150 tonnes. Each installation was a bespoke installation with various parameters taken in to consideration. One of these would surely be the ambient temperatures in the location, along with the quality of fuel in the area, load profile, technical support available in the area and so on.
Ducting , to make sure that the blown air actually passes through the radiator may well help , as might ducting to exhaust the heated air. You could try emailing Paul at ' The museum of internal fire' https://www.internalfire.com/ He has lots of big generating plant and is a friendly and approachable bloke.

 

[gaz1]

dig a well hole and fill with water use looped coils within as it will take ages for it to transfer between the well water and the water in the system but is a real good cooler system

 

[Mikes]

Generators will have radiators and oil coolers designed for the design ambient that they are to work in so for Paris they are probably designed for an ambient of 35 C so rads won't be able to cope with 45 C. It also depends upon how much loading you are putting on the set and if they were designed originally for prime or standby use. ITM are sold all over the world so I would try and get them to give you the set's full spec if you can find the necessary serial numbers from it. It could be that you could fit a radiator with more rows, greater fin density and a larger fan. Alternatively, if the set is a permanent installation then you could pipe it to a separate dry air cooler or adiabatic cooler if you have the space.

 

[Dilkris]

Read all the comments - thankyou all for contributing - I'll start with ITM - I am in the middle of nowhere (400 km from Bamako) so real world additives very difficult to come by. Lots for me to check out it seems but at least I have some directions to follow.

 

[knighty]

dig a well hole and fill with water use looped coils within as it will take ages for it to transfer between the well water and the water in the system but is a real good cooler system

650kw generator running full pelt will be putting about about 650kw of heat too!


are you running both at the same time, or one most of the time then two when you need extra power?

would be better running them both all the time... cooling systems could probably keep up if they only had half the load on them


you said you're spraying water between the fans and the radiators, are the fans blowing through them? that's unusual to me anyway, cooling is much more efficient with fans pulling through radiators

pulling through the radiator you get a nice even flow, pushing through the radiator you get some areas with loads of airflow and some with hardly any - like when you put your hand in front of a fan and some areas blow more than the others


I've done well with misting nozzles in the past, spraying a mist of water over radiators - the water mist evaporates when it hits the hot radiator so you get evaporative cooling - but I guess with where you are and the heat out there water will be a precious/scares resource?

 

[Matrixx]

Hi, I feel your pain, I have installed many generators in Africa 100-3000kVA, if they are overheating is more than likely the radiators are to small for the ambient temperature, if they are second hand they were probably specked for European temps.
there are a few things to check, but a picture would tell all.
Ducting is the plenum in place?
Is the air in sufficient, ie no blocked filters etc if in a container.
Is there anything restricting the airflow through the radiator, any noise attenuation after the radiator if there is it will need to go.
Don't worry about antifreeze, there should be some in but it will have very little effect on the cooling.
One thing you must not do is remove the thermostat (s), it can cause the engine to overheat on certain cylinders.
If it's an old engine, then you may need to look at the water pump and oil pump.
An other point to note is that the diesel must not get above 45 deg C , above this it will derate the generator.

It should have an oil temp and coolant temp, normally the oil temp will be 20 deg higher then the coolant. but i would suspect the radiators are too small, I had some out in Chad which would only take 50% load before overheating, it should just shutdown on over temp, but the quickest way to cool an engine it to start it up and run it as soon as possible (off load).

never heard of ITM, what make of engine is it, cummins, perkins?

thanks

Alex.

 

[Mikes]

Think you will find that the fan is arranged such that it pulls air over the alternator and pushes it through the rad to discharge. This is the norm to ensure that the alternator is kept as cool as possible.

 

[Matrixx]

The alternator has its own fan which is part of the rotor.
It will be a push fan to draw air over the engine and out through the rad.
If it's in a container make sure all the doors are shut, the air needs to follow the designed path.

 

[Dilkris]

Hi, I feel your pain, I have installed many generators in Africa 100-3000kVA, if they are overheating is more than likely the radiators are to small for the ambient temperature, if they are second hand they were probably specked for European temps.
there are a few things to check, but a picture would tell all.
Ducting is the plenum in place?
Is the air in sufficient, ie no blocked filters etc if in a container.
Is there anything restricting the airflow through the radiator, any noise attenuation after the radiator if there is it will need to go.
Don't worry about antifreeze, there should be some in but it will have very little effect on the cooling.
One thing you must not do is remove the thermostat (s), it can cause the engine to overheat on certain cylinders.
If it's an old engine, then you may need to look at the water pump and oil pump.
An other point to note is that the diesel must not get above 45 deg C , above this it will derate the generator.

It should have an oil temp and coolant temp, normally the oil temp will be 20 deg higher then the coolant. but i would suspect the radiators are too small, I had some out in Chad which would only take 50% load before overheating, it should just shutdown on over temp, but the quickest way to cool an engine it to start it up and run it as soon as possible (off load).

never heard of ITM, what make of engine is it, cummins, perkins?

thanks

Alex.

The Engines are by MTU, alternators as stated previously Leroy Somer and the whole "package put together by ITM in what I crudely would describe as a 30' (ish) container. Generators have been "abused" I would say and are run with all doors open, and all sound proof panels (they look like enormous cooker hood filters) removed. My understanding is you never run such units like this - and keeping them enclosed is paramount to air flow etc etc...

We have 2 of these units - only one functioning as the second unit has a communication issue between engine and alternator and we cannot access the fault codes because ITM (who obviously built this part and "own it") won't gives us the pass code - unless we fly a technician out from Paris - and there's plenty of those wanting to journey to Mali as you can imagine.

I have only been on this location for a couple of weeks - so I am picking up the errors of my predecessors, (ie: Engine Overheating?? - "lets open all doors and remove any air flow restricting items... I was always led to believe this is a serious "don't do that")

I will check thermostats present.

We have no issues with alternator overloading - I doubt if it is running at 70% capacity.

My personal feeling is the units are designed for Europe not Africa, (ambient in Mali can reach 46 degrees), should have larger capacity radiators. (I will check for the presence of oil coolers)

You mention whether the plenum is in place - excuse my ignorance - what is that?

Thanks for your input.

 

[gaz1]

i can name a few types of cooling

terracotta water cooling

fit a mix between underground terracotta cooling and you will have good free cooling