281–290 of 399 posts
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Literally destroying a mountainous environment is not clean energy.
But endless fields of solar panels and wind turbines is? That seems like a somewhat arbitrary, fine line to walk.
Finally, a use for the hyperloop
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So I did the math and the average water tower holds something like 1/2 kWh worth of power. (50m tall, storage of 1m gallons, efficiency of 90%) Hydro power storage is fantastic but needs truly ridiculous amounts of water and height deltas to make sense.
https://www.wolframalpha.com/input/?i=gravitational+potentia... I got 450 kWh? Maybe you meant 1/2 MWh
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The heavy iron ore is essentially a large battery storing gravitational energy. In a way it's just another natural energy source. Maybe in the future clean power can be generated from pulling down mountains.
Years ago I visited the Seneca Pumped Storage Generating Station [0] reservoir in person. It's a massive man-made lake on the top of a small mountain in Pennsylvania, USA. They pump water up to it at night (when there is excess energy in the power grid), and let the water out in the day when the demand for energy is high (turning some turbines on its way down). Prior to visiting I had an intellectual understanding of…
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Reminds me of this dam operation around here that pumps water up to a mountain top reservoir during the day when power is cheap and then lets it go at night when it can generate and sell the electricity for more money. I was always in awe of the lake size battery they created.
Pumped hydro is really cool. Also really bad when it fails: https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_... > ... catastrophic failure of a triangular section of the reservoir wall and the release of 1 billion US gallons (3,800,000 m3) of water in 12 minutes. The sudden release sent a 20-foot (6.1 m) crest of water down the East Fork of the Black River. > A broad swath of dense forest was washed away…
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A thousand (1e3) metric tons (1e3 kg) of anything, up a thousand meters (1e3), has 1e9x(10)=1e10 Joules of potential energy on earth (g=~10 m/s2). At 80% conversion (8e9 J) and assuming 1/8 of the energy is "payload" after paying for the train to go up, that's still ~1e9 or a GigaJoule. At a -20% grade, you're looking at a 5km train ride, which reasonably might take a half hour or less (1800s). So, you're generating…
A 20% grade is probably unachievably steep for ordinary railways. Even a 5% grade is considered remarkable. Wikipedia says ( https://en.wikipedia.org/wiki/Saluda_Grade ): Saluda Grade is the steepest standard-gauge mainline railway grade in the United States.[1] Owned by the Norfolk Southern Railway as part of its W Line, Saluda Grade in Polk County, North Carolina, gains 606 feet (185 m) in elevation in less than th…
Great points though!
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So I did the math and the average water tower holds something like 1/2 kWh worth of power. (50m tall, storage of 1m gallons, efficiency of 90%) Hydro power storage is fantastic but needs truly ridiculous amounts of water and height deltas to make sense.
You’re telling me I could fill a typical water tower in 1 hour with a 500 W pump running off a kitchen outlet?
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Years ago I visited the Seneca Pumped Storage Generating Station [0] reservoir in person. It's a massive man-made lake on the top of a small mountain in Pennsylvania, USA. They pump water up to it at night (when there is excess energy in the power grid), and let the water out in the day when the demand for energy is high (turning some turbines on its way down). Prior to visiting I had an intellectual understanding of…
Extra power at night? Where's it coming from?
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Years ago I visited the Seneca Pumped Storage Generating Station [0] reservoir in person. It's a massive man-made lake on the top of a small mountain in Pennsylvania, USA. They pump water up to it at night (when there is excess energy in the power grid), and let the water out in the day when the demand for energy is high (turning some turbines on its way down). Prior to visiting I had an intellectual understanding of…
Extra power at night? Where's it coming from?