Posted By: jamesingramEven today, a nineteenth-century rope drive would be more efficient than electricity over relatively short distances.

Yes, but presumably only if you start with a rotating source of power and the output you want is also something spinning round at a relatively constant speed. If you happen to have a water wheel and want to run a cotton mill then it seems like a fine thing. Not many other applications, though.

If the power is in electrical form at either end (motor at the source or generator at the destination) then it'll be more efficient to put the motor/generator closer to the source/destination whirly thing as the actual wires will have less loss than cables and pulleys and also take a lot less maintenance.

All sounds like nonsense to me when you look at the huge scales of power that we transmit.

Most of what we need power for is heat.
Electricity is pretty good at that.

Rope drive won't light my house or make the TV work either.
And having gone to all this trouble to eliminate noisy fans from PCs etc I don't fancy spinning wheels and yards of rope would be very quiet.

I live on a farm and even I am having trouble finding an application for rope drive.

There are a lot of friction forces and inertia to overcome with mechanical drives.
You may get an advantage if you bolted a water pump directly to a windturbine, but if you had to put that pump 10m down a borehole then it is a different matter.
I am sure we did not swap from mechanical drives to electrical drives because it was less efficient, was more expensive or the 'New World Order' decided to make them some cash and keep us all in our place

Posted By: renewablejohnJust installing a 42 inch blade rack saw on the farm and thought about electric motor but for the hp required a belt drive was a much easier solution.

A belt drive from what?

Posted By: SprocketMost of what we need power for is heat.

There are a few wind turbines in Denmark which have direct mechanical drive for heating applications. The turbine is geared to an axle down the pole which moves vanes in a container of water causing heating.

Didn't somebody link to a you-tube video of a similar but more complicated system somewhere in Asia? Taiwan?

From http://www.tradewindturbines.com/applications.php

"Square Rigger Power

The energy produced by the Square Rigger turbine can be harnessed to generate electricity, via a generator, or provide direct mechanical power to mechanical devices such as pumps.

Electricity can be generated in both on and off grid locations. The design credentials have particular merit in off grid locations but we envisage strong demand from on grid applications particularly when MCS accreditation is achieved.

The high torque generated in the central power gear lends itself very efficiently to providing mechanical power, via a power take off (PTO), which is proven, reliable, 19th Century technology.

We are testing a renewable energy pumping solution for the management of mining legacy issues of contaminated water and we see huge potential around the world for pumping applications in mining, agriculture for drainage and irrigation, water provision, treatment, management, aeration, fish farming, desalination, conservation etc. "

Posted By: SeretA machine that's trying to do both mechanical and electrical work isn't likely to be optimised for either.

Similar to getting one heating system to do both space and water heating

<blockquote><cite>Posted By: Ed Davies</cite><blockquote><cite>Posted By: renewablejohn</cite>Just installing a 42 inch blade rack saw on the farm and thought about electric motor but for the hp required a belt drive was a much easier solution.</blockquote>A belt drive from what?</blockquote>

Tractor pto.

Posted By: renewablejohn

Posted By: djhA couple of weekends ago I watched a ploughing engine lining itself up with a threshing machine so they could get the drive belt properly aligned.

I can't help thinking it would have been easier to plug an electrically-powered thresher into the dynamo on a showman's engine. Mechanical efficiency isn't the only consideration.

That's only done for show, if your using it on a daily basis you make the belt connection permanent and use a pto shaft to your belt drive.

With modern equipment yes. In the days when this equipment was used, no. The name 'ploughing engine' (one of a pair actually) gives you the clue that threshing wasn't its regular job

And when it was threshing, then either it or a horse had to move the threshing machine to the farm before they could start operations, just like a modern combine moves from farm to farm.

Many airports with shuttle trains use belt drive - two recent ones that spring to mind are Minneapolis and Detroit. They work very well for this application.

Of course, other examples that spring to mind are Telepheriques and ski lifts.

Paul in Montreal.