[Karle]

The only thing missing to use renewabe energy is storage. Maybe this is the break-through:

"the hyper simple system that is Energy Cache’s intellectual property and the
first of its kind system for energy storage in the world: a system of buckets on a line that picks up gravel at the bottom of a hill, and moves the gravel to the top of the hill; when the process is reversed the gravel moves back down the hill and powers a generator to produce energy."

There is a short video on the website showing that simple system, basically a ski lift.

What do you experts think?

http://www.energycache.com/

They say it is their intellectual property. First, how can someone claim intellectual property when they just use a ski lift to transport gravel?
Also I have experimented years ago with such a system, so it can't be their intellectual property. Too bad Bill Gates did not invest in my development so I could not file a patent.

[Shaved Monkey]

In Australia we have the Snowy Mountain Scheme a hydro electric system
Basically an upper dam and a lower dam
Brown coal power stations pump water up the hill at off peak times.
The water gets released down the hill at peak times.
Its a battery
It takes 3 to 4 times more energy to get the water up the hill as you get releasing it.
Its not a very efficient energy store but it makes money using cheap electricity and selling expensive electricity.

Its not going to change the world but it is great for rich people with air conditioners and energy company shareholders.

[Gorm]

In Australia we have the Snowy Mountain Scheme a hydro electric system
Basically an upper dam and a lower dam
Brown coal power stations pump water up the hill at off peak times.
The water gets released down the hill at peak times.
Its a battery
It takes 3 to 4 times more energy to get the water up the hill as you get releasing it.
Its not a very efficient energy store but it makes money using cheap electricity and selling expensive electricity.

Its not going to change the world but it is great for rich people with air conditioners and energy company shareholders.

Only in a retard-captitalism is this a good thing...just depressing

[Karle]

It takes 3 to 4 times more energy to get the water up the hill as you get releasing it.
Its not a very efficient energy store but it makes money using cheap electricity and selling expensive electricity.

With water it does not take 3 or 4 times the energy to pump it up than what you get back. The ration is much much better.

For gravel it is probably not that good because of the friction, however, gravel does not cost anything and does not need complicated pipes and valves and so on.

I am going to do some calculations: A sample town of 10,000 people, a hill nearby, and will see how much gravel they need for 2 weeks without sunshine and wind, and how many lift lines. We will see.

[careinke]

Karl, I will be looking forward to your results.

[steam_cannon]

It's become a thing on smaller scale since LED technology has improved. Example:the gravity light

So yeah, it's a great idea and should be very safe too. You could probably even do it in the city if you used huge gravel filled platforms or iron ball bearings filled towers. And if you painted them green, you might make your city like something out of wizard of oz, lol. But seriously, if zoning for hydro-storage or air storage is a problem, gravity still works. So I see this as a reasonable solution. Making it work is just an engineering problem, as in a difficult problem but still a problem that doesn't require too much innovation.

[ROCKMAN]

Gorm - I'm with you: the conversion ratio is probably much better. But as far as the cost of moving water vs rocks: water will beat rocks every day of the week. I move millions of gallons of oil field water every year. On a weight basis no one can move a pound of rock cheaper than a pound of water. And converting that potential energy to kinetic energy: you can but all the water turbines and fittings arer on the shelf today. If those folks developed a way to do that with rocks good for them.

But look at the video again: they have to build at least 50 of those individual lift system to get the required rock to the top of the hill. I don't know what each will cost but I can guarantee you that I could lay a simple pipeline that has the capacity to pump the same amount of potential energy up that hill much cheaper than just one of their lift systems let alone 50 off them. Releasing water from the uphill position requires virtual no energy by comparison: you just open the valves and gravity does the rest. They don’t say so but I gather the power is generated by the weight of the loaded buckets drives the bull wheel at the base. This would require a generator hooked to the bull wheel. They don’t mention having one installed in their prototype…just the electric drive motor used to move the rocks. That motor won’t generate e-.

And lastly the utter bullsh*t about the cost of water. By the pound water costs far less then rock. I buy both so I know. And the water would be recycled just as the rocks will be. The one advantage of their system might be using it in areas where building the two water reservoirs might not be viable.

At first I thought their idea might have some merit even if only marginal. But right now based upon what I’ve seen in the video it looks like a pure scam IMHO. But if someone would fund the project and pay me a nice salary to build it out and run it for a few years until it becomes obvious it’s a money losing idea? Well, hell, sign me up.

[Timo]

I have a grandfather clock that produces its own energy! All i have to do is pull the chains, lifting the weights, which then maintains the energy of swinging pendulum, which propels the minute and hours hands of the clock to move. It is very efficient, and it does not run on electricty, or any other combustible fuel. All it takes is MY energy to pull the chains. I haven't performed an EROEI ratio on this contraption, yet. But, it does keep perfect time. Every 15 minutes, it even plays pretty bells.

[Keith_McClary]

Pumped storage is the largest-capacity form of grid energy storage available, and, as of March 2012, the Electric Power Research Institute (EPRI) reports that PSH accounts for more than 99% of bulk storage capacity worldwide, representing around 127,000 MW.[1] PSH reported energy efficiency varies in practice between 70% and 80%,[1][2][3][4] with some claiming up to 87%.[5]
https://en.wikipedia.org/wiki/Pumped-st ... lectricity

I can't see where Energy Cache gives efficiency numbers.

The mining industry uses conveyor belts, I don't know how the bucket system compares.

At the Los Pelambres opencast Copper Mine in Northern Chile, carbon free electricity is produced in a very original way. Crushed rock containing copper ore is used to generate electricity as it travels down from the high-altitude mine to the processing plant located in the valley below.

The conveyor belt transporting the ore is 1.80 metres wide and 13 kilometres long, going from an altitude of 3,200 metres above sea level down to 1,600 metres. The ten drive motors of the belt consume power only if the belt is carrying less than 800 metric tons of ore per hour. During full operation, the belt carries 8,700 metric tons an hour and functions in generation mode, providing up to 17 MW of power.

In 2007, the belt produced 90 GWh of electrical energy, equivalent to 15% of the mine’s own power needs. One could argue whether this type of electrical energy is truly renewable or not, but it certainly qualifies as zero carbon emission. The system saves about 50,000 metric tons of CO2 per year. It not only reduces the environmental impact of the mine, it also reduces electricity costs, making the site one of world’s most profitable mining operations.
http://www.leonardo-energy.org/copper-o ... lectricity

[Ulenspiegel]

@shaved monkey

Pumped hydro has an efficiency for one cycle of better that 70%, i.e. 100 units electricity that are used for pumping give usually 75-80 units electricity back.