
#1
Nov2512, 08:51 AM

P: 9

Dear Friends,
I need some details to run 1 MW Generator. I found that 3600 Mega Joules/hour (3.6 Giga Joules/hour) required to run 1 MW Generator for 1 hour i.e 1 MWH. 3600 Mega Joules/hour = 102,000 Kgm/sec. I want to know that Can we run 1 MW Generator (1500 rpm) for 1 hour to supply 1 MWH using this 102,000 Kgm/sec. Or Only able to run the 1 MW Generator for 1 sec using that 102,000 kgm/sec? Help highly appreciated. thank you pmk69 



#2
Nov2512, 09:16 AM

P: 217

A 1 MW generator, if properly designed, will deliver 1 MW as long as it has fuel. Not just 1 second.




#3
Nov2512, 09:28 AM

P: 9

102,000 kgm/sec force enough to run 1 MW Generator (1500 rpm) for 1 Hour? This is what I actually need?
OR 102,000 Kgm/sec  required to run 1 MW Generator for 1 sec? 60 x 102,000 = 6120000 Kgm/minute  required to run 1 MW Generator for 1 minute? 60 x 6120000 = 367,200,000 Kgm/hour  required to run 1 MW Generator for 1 hour? thanks pmk69 



#4
Nov2512, 02:40 PM

P: 2,861

Kgmeter required for 1 MWH generator
Power (in Watts) = Torque (in Newton meters) * Angular velocity (in Rads/s)
so Torque = Power/Angular velocity at 1500 rpm the angular velocity in rads/s is... = 2∏ * 1500/60 = 157 rads/s Therefore.. Torque = 1,000,000/157 = 6369 Nm So your generator appears to require a motor capable of producing 6369 Nm of torque at 1500 rpm. Edit: Your generator will keep delivering 1MW for as long as your motor keeps delivering 6369 Mn at 1500 rpm. 



#5
Nov2512, 02:59 PM

P: 2,861

If I have understood correctly you mean..
102,000 kgm/sec = 102,000 x 9.8 = 999,600 Nm/sec Now.. force (in Newtons) * velocity (in m/sec) = power (watts) so what you are saying is that your source is 999,600W. Since 999,600W < 1,000,000W the answer to your question appears to be no. However even if you decide it's close enough your data still doesn't have enough info to answer the question fully. For example how is your source power delivered? Is it in the form of electrical power? linear motion? rotary motion at the right rpm? The generator needs 1MW (6369 Nm, at 1500 rpm) where as you have 0.99MW (?Nm, at ?? rpm). 



#6
Nov2512, 05:08 PM

P: 217

The difference between 999600 W and 1 MW is negligible and stems from rounding errors. The OP converts MW into kg m/sec (I don't know why). I think the word second is the key because it makes pmk69 think the generator would run for only a second.
On the other hand, perhaps the OP just want to ask the amount of energy needed to run the generator 1 hour, but it isn' so clear. 



#7
Nov2612, 02:33 AM

P: 9

Thanks for your reply. Available energy is in the form of Linear and it should be converted into Rotary Motion using Gear Box (Like Wind Mill) to give required RPM, For example 1500 RPM, to run a 1 MW Generator. So, I need to know whether the said (1,02,000 Kgm/Sec) energy can be used to run a 1 MW Generator for 1 Hour to produce 1 MWH? 



#8
Nov2612, 02:47 AM

P: 2,861

In my book "Kgm/Sec" is a ambiguous unit because force isn't measured in kg but Newtons. So can you tell us how you arrived at 1,02,000 Kgm/Sec ?
kg.m/sec looks like force (kg) x velocity (m/s) which equals power not energy. So asking how long it will run a 1MW generator is meaningless. It's like asking how long can a 100bhp car engine can deliver 100bhp? As I said above.. 102,000 kgm/sec = 102,000 x 9.8 = 999,600 Nm/sec = 0.99 MW which is less then 1MW so the short answer is no. You can't run a 1MW generator from 102,000 kgm/sec for any length of time (but it's close if you ignore losses in the generator and gearbox). 



#9
Nov2612, 04:09 AM

P: 9

http://www.convertme.com/en/convert/power/ Simply to say, How much energy (in Kgm) I need to run 1 MW generator for 1 hour. I have to store available mechanical energy (Linear) and used that energy to run the Generator. thanks pmk69 



#10
Nov2612, 05:15 AM

P: 2,861

First lets assume the generator and gear box are 100% efficient.. Energy (in Joules) = Power (in Watts) * Time (in seconds) = 1MW * 3600 Seconds = 3,600 MJ You can then convert that to other units... 3600 MJ = 3600 M N.m or 3,600,000/9.8 = 367,346 Kgm Could be done with 367,346 kg of water lifted 1 meter or 36,735 kg lifted 10m etc However most generators are going to be less than 40% efficient so in practice you need to store at least 100/40 = 2.5 times that much energy and probably more like 4 times. Plus whatever the pump uses to lift the water into storage. 



#11
Nov2612, 06:02 AM

P: 9

this is what I actually need. If I want to run 1 MW generator (for example, theoretically 100% efficient) for 1 hour is 367,346 kgm.
For 24 Hrs = 367,346 x 24 = 8,816,304 kgm For 365 Days(1 Year) = 8,816,304 x 365 = 3217950960 kgm i.e. 3217950.96 tonnesm or 3.21 million tonnes  m Is this correct? anyway great thanks to you. pmk 



#12
Nov2612, 06:09 AM

P: 9

how to mark the "Helpful" button?




#13
Nov2612, 06:10 AM

P: 9

if reply is helpful to solve the issue, we have to mark the reply as "Helpful" and Mark the thread as "Solved"? How can we do it here?
thanks pmk69 



#14
Nov2612, 07:43 AM

P: 9

Is this conversion correct?
3600 MJ = 3600 M N.m or 3,600,000/9.8 = 367,346 Kgm OR this one is correct? 3600 MJ = 3,600,000,000 Joules = 3,600,000,000 Nm = 36,000,000 Kgm regards, pmk69 



#15
Nov2612, 10:47 AM

P: 2,032

EDIT: Nevermind, it all become clear.




#16
Nov2612, 11:38 AM

Mentor
P: 10,853

3,600,000,000 Nm = 360,000,000 kg*m * g (with the approximation of g=10m/s^2) 


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