Energy Generation through Gravity (mining operation monorail)

[danny.mcshane]

No, each cart is responsible for 1/16 of that value. You don't have to care about the number of carts if the amount of mass lowered at the same time is constant.

But there will be 16 carts full of 69.44kg of ore all moving down at any 1 time. So the amount of mass being lowered will be 1111.04kg per meter per second.

 

[sophiecentaur]

What has to be more? You worked out the 13.6kW we had all the time.

No, each cart is responsible for 1/16 of that value. You don't have to care about the number of carts if the amount of mass lowered at the same time is constant.

I have no idea where this 1RPM comes from, but it is wrong. Your generator needs something like 15kW as design power (a bit more is fine, a bit less is also fine if you can use the brakes), the design rotation speed depends on the mechanism between monorail and generator.

You should roughly match the designed power (or at least don't be above it) and be in the right RPM range (not above the specifications) at the same time.

You will need the brakes for when there is no load on the generator, of course. There may well be a problem with speed regulation as the alternator will need to be run within fairly tight limits and it will not be 'convenient' to regulate the speed of the rock carrying to fit in with the electrical demands.

I am rapidly coming to the conclusion that a diesel generating set is the right answer for this application. Off the shelf, a known cost and can be sold afterwards. A number of small petrol generators could be even more practical. A bit of lighting and a TV would easily be fed from a 1kW set from a DIY / tool store.

 

[danny.mcshane]

Sorry I should have said, the residence block has 1500 people living in it. The site is supplied by mains electricity although lately this has been off more than it has been on. Typically we see cuts regularly through the day but they are short. On a night it is possible to have no mains supply at all.

When the power stops to site we stay running for about 30 minutes through the UPS type thing they have.

Essential processes are powered by generators because that makes money. Workers are left in the dark as we don't matter. We had a generator of our own, probably like the one you are mentioning. It got very difficult though when the supervisors had power and the workers didn't. We took the decision to use it as a sort of emergency light system.

We are now in a kind of all or nothing scenario where either everyone has power or no-one does.

 

[mfb]

But there will be 16 carts full of 69.44kg of ore all moving down at any 1 time. So the amount of mass being lowered will be 1111.04kg per meter per second.

No, and I have no idea how you combined your numbers to get that value.
250 tons/hour over 20m is 5000 tons*meters/hour, or 1389kg*meter/second.