Networked Wind Power For Base-Load Stability
by John Laumer, Philadelphia on 01. 1.08
It's common sense that at any point in time, some wind arms are making very little or no electricity, while others, nearby, are cranking at peak output as a weather front passes or storm brews. In theory, linking wind farms together might well result in a stable average output, once enough wind farms are installed in a region. TreeHugger's Jeremy gave this some coverage:- last year, incorporating some cool graphics.
The question is, how large the area, and how many wind power linkages are needed, to hit that sweet spot where base load stability equivalence is reached? After how much investment does such a network begin to be cost effective?
Before we get to geography and the number of utilities involved, some analogies might help frame the concept.
Weather analogy:- Just as an climate can be thought of as the average of all weather, nearby, and grid interlinked, wind farms produce a collective output that physically averages the forces of nature: 'gusty and turbulent winds reach Kansas City today, reaching St. Louis by early tomorrow morning."
WWW analogy:- The global average number of persons "on-line" at any instant remains high, regardless of multiple time zones and cultural practices, because all nations are physically linked. If the world had separate internets, one for each continent, for example, information flows would be substantially bumpier through the passage of day to night, and so on.
Cristina Archer and Mark Jacobson, authors of a recent paper about this, published in the American Meteorological Society's Journal of Applied Meteorology and Climatology, came up with the Hamster Analogy.
It's a bit like having a bunch of hamsters generating your power, each in a separate cage with a treadmill. At any given time, some hamsters will be sleeping or eating and some will be running on their treadmill. If you have only one hamster, the treadmill is either turning or it isn't, so the power's either on or off. With two hamsters, the odds are better that one will be on a treadmill at any given point in time, and your chances of running, say, your blender, go up. Get enough hamsters together, and the odds are pretty good that at least a few will always be on the treadmill, cranking out the kilowatts.The combined output of all the hamsters will vary, depending on how many are on treadmills at any one time, but there will be a certain level of power that is always being generated, even as different hamsters hop on or off their individual treadmills. That's the reliable baseload power.
The connected wind farms would operate the same way.
The researchers found that nearly a third to a half of yearly-averaged wind power from 10 or more interconnected wind farms can be used as reliable baseload electric power.
A full copy of the paper is available from Standford University, here (pdf file).
If the hamster analogy has your brain fired up enough to think about the entire renewable power menagerie at once, have a look at this related post on the Energy Blog.
Via::Stanford News Service, "Study finds that linked wind farms can result in reliable power" Image credit::Cristina Archer and Mark Jacobson, Figure:- "Hours And Energy Output - 11 Stations" from the paper "Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms."
Use wind power to charge electric vehicles. But oh, we can't do anything smart, never mind.
I guess intermittent wind is rough on the power plants and makes them less than enthusiastic about Wind Power.
I guess intermittent wind is rough on the power plants and makes them less than enthusiastic about Wind Power.
There was talk about wind farms filling tanks of compressed air that could then be used when needed. Depending upon how efficient the compressed air system is it could be a viable solution.
There are a lot of ways to save the energy created by "surplus" wind energy.
The compressed air was (is?) going to be used like a turbocharger for fossil plants, forcing more air into the combustion chamber, raising efficiency.
There is an island in/around New Zealand that uses a huge flow battery.
Oh, you could go ahead and split water for the vaporware hydrogen economy - use it anytime...
Wind makes sense. Our outdated grid doesn't.
I think the knowledge on how to fix it exists - but how do we get it done?
- Dave
using this idea for hydrogen... maybe one day... but not anytime soon...
reminds me of an article on using windfarms to power water purification plants. you can't store wind energy, but you can store water, so that seems like a good way to make fresh water...
Dave, you raise a very interesting question: how do we get it done. It's a pretty monumental task, to say the least. So much could be achieved with "green" power and more efficient ways of transporting and storing said power. But it seems like in this 21st century, politicians all over the globe are afraid of making big decisions. No one wants to undertake any really big projects, which is so very sad indeed.
The technology is ready for the most part, all we need is someone to step up and use it.
And you know, we already have a globally interconnected grid in place. Not a power-grid, but a data grid, to good old internet. So surely if we can make an immense data network, then it's a relative piece of cake to do the same for electricity. Routers become transformers, fibre becomes copper (or some of those fancy superconductors sci-fi is so proud of) and there you have it. Globally distributed power.
On a different note, regarding storing surplus power: Hydroelectric is a nice alternative in my opinion. When you have too much power, you pump the water up. When the demand becomes too great, you reverse the process and let the water come back down through the turbines. I realise there are, of course, problems with dams and the likes, but it doesn't have to be a giant monstrosity. Small scale interconnected powerplants are definitely the way to go here.
To Edgars comment regarding using wind to charge vehicles, add the thought that buildings are starting to use wind turbines that are integrated into their architecture. So, not only could you charge vehicles thus, you could also dramatically improve base load stability by spreading the points of power production into urban areas.
Hamsters everywhere.
Good article. This would certainly be a solution to the baseload power problem (and good fodder to argue those who maintain wind can't be used somehow for baseload). If you add in other output leveling methods including pumped storage hydro, compressed air as mentioned above, hydrogen production, etc., a stable grid is entirely possible.
How to proceed is the hard part - a certain amount of chicken/egg issues exist. But some government somewhere is simply going to go for it, and possibly set the standard that many others will follow. As treehuggers, we can try to make a difference by lobbying our own governments, if not to lead then at least follow in the footsteps of someone else's good work.
Look, its easy, people as a whole have to give a damn first, then the companies will be slightly interested and wallow around a few years until they realize they are getting beat at their own game, and then try to catch up again. Its a great analogy to the internet (ie Microsoft), with the larger computer powers having to totally reform their businesses after realizing the little innovative guys were on to something. Large companies do not turn on a dime like a ten-person company can.
Wait and be patient, and innovate - then the large companies will jump in full force, after you've made an impression on society...
Dave - Much as I'd love to take the credit (being from New Zealand), the island you're thinking of is Tasmania, just off the southeast coast of Australia.
As for the article in general, well done on raising the issue but I think you've missed the point. There is no need to start with thought experiments equating the proposed system to the www or similar. The system ALREADY EXISTS, it's called a national grid. In places where it makes economic sense to do so (e.g. europe, asia, the americas) it is in some cases the international grid. Utilities and generators already have a huge interlinked system to manage generating assets, loads etc. It predates the www by many years.
A generator, like some guy who owns a bunch of windfarms, sells the electricity onto the grid. If he sells a certain amount of his generating capacity as "base load" then he is guaranteeing he will always produce it. This means that if the wind isn't blowing, he has to provide it from somewhere else. This could mean providing it from another of his vast distributed network of wind farms, or it could mean buying electricity on the spot market from the guy down the road who has a gas turbine power plant on standby. Either way, the mechanism for distributing, monitoring, providing, and paying for the power is pretty much the same.
It is all very very simple and is purely a matter of the guys who generate power and own wind farms deciding it makes economic sense and coming up with some arrangement between themselves. It will happen as a matter of course as wind begins to make up a larger part of the generating portfolio. No new infrastructure (except for the wind farms!) is required.
Additionally - it doesn't get around the issue of storage. As wind begins to make up a greater and greater share of power generation there will be times when it exceeds the total requirements of the grid. In this case you can either a) feather the turbines to reduce the power generated or b) store the power (either in an EV, a battery, hot water, ice etc etc).
Finally, Bram, sorry but it's by no means a relative peace of cake. Transmitting power around the place is expensive (in terms of infrastructure) and inefficient. Stringing up a cable from NY to London is not an option. For it to be any real use the cable would have to be capable of carrying 10's of gigawatts of power. I couldn't give you an exact figure for the dimensions of such a cable off the top of my head, but trust me, it would be really really big and impractical and unrealiable and probably borderline impossible. Something along the lines of the channel tunnel would probably get you in the ballpark, only you'd still probably have so much voltage drop along the way that it'd be cheaper (and more environmentally friendly) to ship diesel across by ship and burn it at the destination.
SO!!!! Yes yes to more windfarms, just keep them coming and the power will be used, ignore all the people who say that they'll lead to grid instability as they're wrong (mawson base in antarctica uses a load bank to achieve 90%+ wind penetration), but don't stop thinking about storage!