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The most spectacular example of regenerative braking are trains that are used in Scandinavia, heavily loaded with iron ore that is transported to the coast: "I
by ols 5y ago
The most spectacular example of regenerative braking are trains that are used in Scandinavia, heavily loaded with iron ore that is transported to the coast:
"In Scandinavia the Kiruna to Narvik electrified railway carries iron ore on the steeply-graded route from the mines in Kiruna, in the north of Sweden, down to the port of Narvik in Norway to this day. The rail cars are full of thousands of tons of iron ore on the way down to Narvik, and these trains generate large amounts of electricity by regenerative braking, with a maximum recuperative braking force of 750 kN. From Riksgränsen on the national border to the Port of Narvik, the trains use only a fifth of the power they regenerate. The regenerated energy is sufficient to power the empty trains back up to the national border. Any excess energy from the railway is pumped into the power grid to supply homes and businesses in the region, and the railway is a net generator of electricity." (via https://en.wikipedia.org/wiki/Regenerative_brake#Conversion_to_electric_energy:_the_motor_as_a_generator https://en.wikipedia.org/wiki/Regenerative_brake#Conversion_... )
- mechanicalpulse 5y agoThis is fascinating. So they are essentially harvesting the gravitational potential energy of the iron ore at altitude to charge the batteries (and then some) for the cargoless return trip. Outstanding.
- furiousjulius 5y agoReminds 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.
- rpmisms 5y agoMaybe this could be applied to water towers? That's a lot of potential energy just sitting there.
- deleted 5y ago[deleted]
- dharmab 5y agoWater towers are already used that way- water is pumped in during off-peak time and used during peak time.
- mikepurvis 5y agoRight, but that's about maintaining pressure and supply when everyone wants a shower at the same time in the morning, not about harvesting the energy of it all flowing downhill.
- ClumsyPilot 5y agoPressure is energy
- bigiain 5y agoNope. Energy is force times distance. You need to know more than just pressure to calculate energy. (A bicycle tire at 120psi has a lot less energy than a truck tire at 90psi.)
- deleted 5y ago[deleted]
- cobaltoxide 5y agoNot enough volume. And you have to maintain water in the tower in order to keep the water distribution system pressurized.
- sigstoat 5y agopumped storage systems are so large as to be geographic features. there isn't much energy in a water tower. and that water is already doing work, pressurizing the water system.
- dreamcompiler 5y agoPumped hydro is one of the cheapest ways to store electricity iff you have the topography available to create the uphill lake and plenty of water available to compensate for evaporation.
- codeismath 5y ago> I was always in awe of the lake size battery they created. This is exactly the feeling I had when visiting the Seneca Pumped Storage Generating Station that I mentioned in one of my other comments that I just posted before seeing your post. Truly awe inspiring. (Links provided in my other comment). Do go visit one of these!
- tshaddox 5y agoPumped hydro is really cool. Also really bad when it fails: https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_Station#2005_upper_reservoir_failure 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 and scoured to bedrock by the escaping flow. A tidbit that will be interesting to any programmer or engineer: one of the causes of the failure was that the high-water gauges were moved to above the height of the dam wall because someone was annoyed by false positives.
- jashephe 5y agoTaum Sauk is unusual in that the dam fully surrounds the upper reservoir (i.e. the lake was made from scratch), although certainly all types of dam can fail.
- bigiain 5y agoAll types of dams can be shittily maintained: https://en.wikipedia.org/wiki/Oroville_Dam_crisis https://en.wikipedia.org/wiki/Oroville_Dam_crisis
- bqmjjx0kac 5y agoSounds like they hired Homer Simpson to operate the plant.
- tobltobs 5y agoThe same as a quarry truck in Switzerland: https://www.autoblog.com/2019/08/26/edumper-electric-mining-truck-self-charging/ https://www.autoblog.com/2019/08/26/edumper-electric-mining-...
- Schweigi 5y agoWhich has a nearly infinitive range because because of how the quarry is set-up! In a way the perfect use case for electrification. The truck is able to drive anywhere and much more flexible - e.g. compared to a conveyor belt or cable car solution.
- FridayoLeary 5y agoThe 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.
- sigstoat 5y ago> Maybe in the future clean power can be generated from pulling down mountains. it takes a lot of power to dismantle mountains and load them onto trains. and folks get real grumpy about mining operations leveling off mountains.
- _carbyau_ 5y agoAnd it sounds like a rather visible ... race to the bottom, as it were. :-)
- perihelions 5y ago>Maybe in the future clean power can be generated from pulling down mountains. With added bonus efficiencies from combusting the coal that fortuitously falls out!
- deleted 5y ago[deleted]
- lwansbrough 5y agoThis idea is sort of being explored already: https://www.youtube.com/watch?v=itbwXMMkBQw https://www.youtube.com/watch?v=itbwXMMkBQw There's other ways of doing this too. Rolling a ball up a hill, inflating a balloon under water, etc.
- spurgu 5y agoThat looks like a real life battery level indicator.
- quickthrower2 5y ago
- throwawayboise 5y agoWhat does the equation look like when you subtract the energy used in the actual mining, though?
- brightball 5y agoI’ve seen something similar to this with large dump trucks made for hauling loads down mountains. They generate so much power fully loaded on the way down that they can make the trip all the way back up.
- EamonnMR 5y agoAn older strategy was to connect ore cars together so that the full train going down hill would pull the empty train going up hill. It was depicted in The Railway Series
- jcrawfordor 5y agoARES (Advanced Rail Energy Storage) has been trying to commercialize purpose-built facilities of this type, with the first currently under construction in Nevada. They've gone through a number of design revisions but what they're building right now seems just just be multiple-unit trains full of gravel on straight lines. They've also proposed a system of autonomous trains loading and unloading concrete blocks via switchyards, but I imagine they are holding off on this more complex design for a larger installation, and the current site is a gravel quarry so they're using native materials. Advertised efficiency is over 90% at 5MW per rail line.
- achow 5y agoSame as this truck.. This Huge Electric Dump Truck Never Needs to Plug In https://www.wired.com/story/this-huge-electric-dump-truck-never-needs-to-plug-in/ https://www.wired.com/story/this-huge-electric-dump-truck-ne...
- fierro 5y agoprobably not net positive if you factor in the energy required to load the ore onto the train at the top.