-
We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.
renewable energy power plant too good to be true?
- Thread starter semo
- Start date
PlasmaBomb
Lifer
I particularily like the piece in the article which says
good pun 😀
Well wind power is getting down in cost where it is competative with coal and nuclear (the 2 biggest and cheapest sources of power). However this obviosuly is promising much more. I just find it kinda hard to believe that a single wind turbine could be so powerfull, i've seen lots of pics of the 1000+ MW turbines and generators in a nuke plant and they are massive. I jsut find is somewhat hard to believe that a bunch of kites (even though they are obviouslly very large) could provide that much power. I mean jsut look at a 1.5MW wind turbine and see how big each blade is, and these kites would combine to generate 2000 times as much power as one of those blades?
EIDT: heres a pic of the stator and rotor for a 1000MW turbine.
EIDT: heres a pic of the stator and rotor for a 1000MW turbine.
There were some interesting wind-power ideas in a recent Scientific American (September 2006 issue) - this one looks similar to one of them.
Things in the article included:
1. windmill-like kites at 10K ft, in the jetstream
2. kites along a wire that were raised by the wind, and the tether would have a generator in it that's turned by the up/down motion of the kites (keepint all the heavy stuff on the ground)
3. a helium-filled blimp-like balloon that spins in the wind due to its shape
Things in the article included:
1. windmill-like kites at 10K ft, in the jetstream
2. kites along a wire that were raised by the wind, and the tether would have a generator in it that's turned by the up/down motion of the kites (keepint all the heavy stuff on the ground)
3. a helium-filled blimp-like balloon that spins in the wind due to its shape
cheesehead
Lifer
I dunno about a megawatt, but wind power is the way of the future, or at least until we can make better solar panels.
imported_Seer
Senior member
Fusion is the way of the future, actually.
Windpower certainly has it's place in the future energy markets. And I'm not even an enviromentalist or anything. The fact is that it is currently economically a good idea to build wind power, and since its a new technology the price will likely come down to be even more competative. However, the intermitant nature of wind provides many problems if you get over a few percent, and by the tiem you getting to like 10%+ the cost of backup generation or energy storage systems makes wind less economical. However, I certainlly believe that wind power will continue to grow (it is currently the fastest growing tech in terms of %). Also, the no CO2 or harmfull chemicall emissions is a big added bonus.
Fusion is stil sorta the "Holy Grail" of energy technologies right now, everyone thinks its the best thing since sliced bread, but so far nobody has gotten it working yet. I certainlly hope that it ends up being the energy source of the future, but that will have to be the distant future, in the near future it has no place. Even if they got a concept model workin right now it would probably be 10 years before they got a full scale model working, and then another 10 years before they started building commercial fussion plants. It is important to point out that fusion plants would likely NOT be the solutions to *cheap* power since they would have the same problem fission plants have, a very high capital cost to build. However, they don't produce the long lived radioactive waste, and they have a more stable fuel supply, and there is no risk of radioactive contamination of something goes wrong, so its like a normal fission plant but without all the bad stuff that scare people about them.
Fusion is stil sorta the "Holy Grail" of energy technologies right now, everyone thinks its the best thing since sliced bread, but so far nobody has gotten it working yet. I certainlly hope that it ends up being the energy source of the future, but that will have to be the distant future, in the near future it has no place. Even if they got a concept model workin right now it would probably be 10 years before they got a full scale model working, and then another 10 years before they started building commercial fussion plants. It is important to point out that fusion plants would likely NOT be the solutions to *cheap* power since they would have the same problem fission plants have, a very high capital cost to build. However, they don't produce the long lived radioactive waste, and they have a more stable fuel supply, and there is no risk of radioactive contamination of something goes wrong, so its like a normal fission plant but without all the bad stuff that scare people about them.
futuristicmonkey
Golden Member
I don't understand these people that say fusion is the holy grail. It is going to take about 20+ years at the current rate to barely break even on energy in/out.
Fission right now is the _best_ damned energy source in the world. It does, however have a few, undeserved problems.
Firstly, the population at large is ignorant about it. Chernobyl is now impossible, and TMI was a stupid, little accident that was made harmless by the safety precautions in place (ie full containment structure).
Secondly, waste management is retarded in the West. Those damn treaties of the 60's have prevented us from building breeder reactors. Basically, after a small processing stage you can throw the waste of a normal PWR or BWR into a breeder whereby the unused U-238 is transformed into Pu-239. Unfortunately, this Pu-239 is way easier to turn into a bomb than U-235 is. If we could breed this stuff, we'd turn our 150 year supply of fissile uranium into a 150 million year supply. We'd just need to beef up security.
And though it is like hydro-power with regard to high initial investment costs, nuclear power is pretty damned cheap. A $7 USD (FY2003) fuel rod can emit as much energy as 1 ton of coal. And this uranium isn't going to be spewing 1 ton of those nasty oxides into the atmosphere as a result of its use.
Wind power wastes space, hydro power floods land (and on the Canadian Shield causes peat to die and float on the top of the floodwater, relasing thousands of years of CO2 into the atmosphere). Solar power is the only renewable resource we have that, if we could beef up our efficiency (NASA's max is about 18%, IIRC) we might actually be able to use that ~1300W/m^2 that hits the earth. That and nano-tech battery/capacitors on the drawing boards right now could only hope to fill the gap that nuclear power plants should (rightfully) have.
Please, people, don't support coal power. We may have 8000 years of the crap under our asses, but an average coal plant needs 90,000 tons a DAY. That's 90,000 tons of crap getting into our atmosphere and raining down on us.
Fission right now is the _best_ damned energy source in the world. It does, however have a few, undeserved problems.
Firstly, the population at large is ignorant about it. Chernobyl is now impossible, and TMI was a stupid, little accident that was made harmless by the safety precautions in place (ie full containment structure).
Secondly, waste management is retarded in the West. Those damn treaties of the 60's have prevented us from building breeder reactors. Basically, after a small processing stage you can throw the waste of a normal PWR or BWR into a breeder whereby the unused U-238 is transformed into Pu-239. Unfortunately, this Pu-239 is way easier to turn into a bomb than U-235 is. If we could breed this stuff, we'd turn our 150 year supply of fissile uranium into a 150 million year supply. We'd just need to beef up security.
And though it is like hydro-power with regard to high initial investment costs, nuclear power is pretty damned cheap. A $7 USD (FY2003) fuel rod can emit as much energy as 1 ton of coal. And this uranium isn't going to be spewing 1 ton of those nasty oxides into the atmosphere as a result of its use.
Wind power wastes space, hydro power floods land (and on the Canadian Shield causes peat to die and float on the top of the floodwater, relasing thousands of years of CO2 into the atmosphere). Solar power is the only renewable resource we have that, if we could beef up our efficiency (NASA's max is about 18%, IIRC) we might actually be able to use that ~1300W/m^2 that hits the earth. That and nano-tech battery/capacitors on the drawing boards right now could only hope to fill the gap that nuclear power plants should (rightfully) have.
Please, people, don't support coal power. We may have 8000 years of the crap under our asses, but an average coal plant needs 90,000 tons a DAY. That's 90,000 tons of crap getting into our atmosphere and raining down on us.
The most depressing thing about nuclear power plants is how absolutely nothing new has happened in 30 years. My dad has a masters in nuclear engineering, and every single type of reactor that is talked about now as being "next generation" was designed by the time he was in college in the 70's. People act like breeder reactors, gas cooled reactors, or liquid metal reactors (these are called the generation 4 reactors) are somethin new. However, they were all built and operated at least 30 years ago. The problem of course is that everyone is already so scared of nuclear power that building a "new" type of reactor really scares people. So basically the nuclear power plants we have now are 30% efficicent and only use 1/100th of the energy potential of the fuel. Just think about how much a coal plant would cost if it were so horribly inefficient, and then think about how much better nuclear power would be if it actually used intellegent reactor designes instead of the current designs (the current ones are simple and easy to understand, but they should simply have been a stepping stone to the better types of reactors, not the permanent solution).
frostedflakes
Diamond Member
That is really cool. And one of the biggest (or maybe even the only) arguement against wind power, that it hurts bird population, should not be an issue with this design.
Anyone who argues that wind power is bad based on bird kills is just ignorant. I've seen several studies on bird kills and basically it seems like the numbers kill are alot till you realise how many BILLIONS are killed by running into buildings every year etc...
House cats kill 100 Million-1 Billion birds a year, and nobdy is trying to ban them even though they are thousands of times more deadly to birds than wind turbines are.
House cats kill 100 Million-1 Billion birds a year, and nobdy is trying to ban them even though they are thousands of times more deadly to birds than wind turbines are.
frostedflakes
Diamond Member
I tend to agree, but was just pointing that out. 🙂
The idea of the plant would be:
You have a "fallen" merry-go-round (vertical axis, rotating parallel with the land).
You have kites tethered to every spoke.
YOU rotate slowly the wheel (you put energy in this).
Hoping to keep the kites' cables straight (not a mess), you do the following:
-when the rotation of the wheel moves the kite downwind, the kite will be a parachute, the kite is pulled by wind. This pull will produce electricity
-when the rotation of the wheel pulls the kite upwind, the kite will act as a wing and it will be pulled up. What you earn here is the difference between the kite acting as an airbrake in the wind (pulled by the wind), and the energy you need to pull the kite back (with the kite acting as a wing).
This could work well, but there are certain problems:
1. You must get the kites high (zero-level wind speed is some 3m/s average, when you reach 1000m high you get to 9m/s. You could drive kites up there, but building conventional wind generators up there is not possible.
2. You must unfurl the system at short notice, and without making a cable mess if the need arises. Keeping kites and cables clear of each other could be the biggest problem
3. This is a drag-based system, with lower efficiency than lift-based blades of the wind turbines
How much power could you get?
Well, assuming a "best case" - 9m/s wind, a 3 m/s cable move, a kite that has an area of 750 square meters (7500 square feets, as NASA tested a parafoil parachute)
Force in cable is 1/2 * rho * v^2 * A * Cd , where v is 6m/s, A is 750 sqm, Cd is a coefficient of drag - let's say 1 (cars have 0.25-0.45), air density is 1.1kg/cubic meter
So, force would be some 15000N, or some 1.5tons of force (3000 pounds).
The power you could get from this? P = F*v, where v is the 3 m/s - so from a single kite you could get P = 45 kW
You lose some of it on the return trip, and on the return trip you won't get back any energy from the wind. Also, you could need a bit of time to orient the kite, so you could get some 15kW from it.
To get this from a wind turbine (in the same wind): wind energy at 1kW/sqm, turbine efficiency some 50%, you need a turbine sweeping 30 square meters - this is a turbine 7 meters in diameter. If the wind speed on the ground is lower than what the kites encounter at altitude, the size of the turbine increases: if you only have 3 m/s, you have 100W/m2, 50W/m2 usable, and you need a turbine sweeping 300 square meters (20 meters diameter).
EDIT: wind parameters from a graph inside the rotokite presentation: http://sequoiaonline.com/blogs/pdf/06cdc.pdf
You have a "fallen" merry-go-round (vertical axis, rotating parallel with the land).
You have kites tethered to every spoke.
YOU rotate slowly the wheel (you put energy in this).
Hoping to keep the kites' cables straight (not a mess), you do the following:
-when the rotation of the wheel moves the kite downwind, the kite will be a parachute, the kite is pulled by wind. This pull will produce electricity
-when the rotation of the wheel pulls the kite upwind, the kite will act as a wing and it will be pulled up. What you earn here is the difference between the kite acting as an airbrake in the wind (pulled by the wind), and the energy you need to pull the kite back (with the kite acting as a wing).
This could work well, but there are certain problems:
1. You must get the kites high (zero-level wind speed is some 3m/s average, when you reach 1000m high you get to 9m/s. You could drive kites up there, but building conventional wind generators up there is not possible.
2. You must unfurl the system at short notice, and without making a cable mess if the need arises. Keeping kites and cables clear of each other could be the biggest problem
3. This is a drag-based system, with lower efficiency than lift-based blades of the wind turbines
How much power could you get?
Well, assuming a "best case" - 9m/s wind, a 3 m/s cable move, a kite that has an area of 750 square meters (7500 square feets, as NASA tested a parafoil parachute)
Force in cable is 1/2 * rho * v^2 * A * Cd , where v is 6m/s, A is 750 sqm, Cd is a coefficient of drag - let's say 1 (cars have 0.25-0.45), air density is 1.1kg/cubic meter
So, force would be some 15000N, or some 1.5tons of force (3000 pounds).
The power you could get from this? P = F*v, where v is the 3 m/s - so from a single kite you could get P = 45 kW
You lose some of it on the return trip, and on the return trip you won't get back any energy from the wind. Also, you could need a bit of time to orient the kite, so you could get some 15kW from it.
To get this from a wind turbine (in the same wind): wind energy at 1kW/sqm, turbine efficiency some 50%, you need a turbine sweeping 30 square meters - this is a turbine 7 meters in diameter. If the wind speed on the ground is lower than what the kites encounter at altitude, the size of the turbine increases: if you only have 3 m/s, you have 100W/m2, 50W/m2 usable, and you need a turbine sweeping 300 square meters (20 meters diameter).
EDIT: wind parameters from a graph inside the rotokite presentation: http://sequoiaonline.com/blogs/pdf/06cdc.pdf
Reading the document, the builders present a kite with 5 square meters area, which uses lift and drag, to produce about 1.5kW of power (average), with 6 minutes of power generation and 80 seconds of recovery. They expect a 50 sqm kite to generate 200kW in 12m/s wind speed (27 miles per hour)
My calculations for the 50 sqm, 12 m/s wind at a kite speed of 0.5 m/s would be:
F = 3600N, P=1.8kW max.
It seems the design power is generated by drag in a small proportion, and uses lift for almost everything (the kite will fly in "eights" in the wind). The eights seem to be about 40m from end to end, and their period is 5s - so the lift is obtained from a 16+m/s apparent wind (35mph). The force from lift would be about 15 times larger than the force from drag
My calculations for the 50 sqm, 12 m/s wind at a kite speed of 0.5 m/s would be:
F = 3600N, P=1.8kW max.
It seems the design power is generated by drag in a small proportion, and uses lift for almost everything (the kite will fly in "eights" in the wind). The eights seem to be about 40m from end to end, and their period is 5s - so the lift is obtained from a 16+m/s apparent wind (35mph). The force from lift would be about 15 times larger than the force from drag
TRENDING THREADS
-
Discussion Zen 5 Speculation (EPYC Turin and Strix Point/Granite Ridge - Ryzen 9000)- Started by DisEnchantment
- Replies: 25K
-
Discussion Intel Meteor, Arrow, Lunar & Panther Lakes + WCL Discussion Threads
- Started by Tigerick
- Replies: 25K
-
Discussion Intel current and future Lakes & Rapids thread- Started by TheF34RChannel
- Replies: 24K
-
-
