Power Electronics Help to Control Electrical Grids

An anonymous reader writes: "IEEE Spectrum magazine has a timely article about how power electronics are proving necessary for the widespread connection of wind turbines to the electric power grid. It explains many issues that currently make it difficult to utilize wind power. Older articles discuss other issues affecting the nation's power grid."

Comments

Control is the key...

[The Eye of the Behol]

Maybe what we need is more control over the power, we need better systems and routines to warn us before something goes wrong. Not after.

Simple Tweakage

[EvilTwinSkippy]

The problem with power distribution is an imbalance between supply and demand. More efficient switching systems are like tossing a coffee can tailpipe on a honda. Sure you get a few extra horses out of it, but a Taurus with a 3.6 liter V6 is going to leave you in the dirt.

We either need more power plants, to curb demand, or a fairly efficient way of storing excess power capacity in the winter to be used in the summer.

Everything else might buy you time, but it is only delaying the inevitable.

Re:Simple Tweakage

[evilWurst]

"or a fairly efficient way of storing excess power capacity in the winter to be used in the summer. "

Storing a season's worth of extra power for a season's worth of time is unworkable. However, storing excess power during the low-demand part of the day to ease spikes in demand later that same day...that is being worked on already. It was in either Discover magazine or the MIT Technology Review, but they're working on what is basically a huge fuel cell battery. Right now it's just at a military base, but the idea is to put one of these big batteries in every major city to act as a buffer. It'd ease both the peak demand on the power plants AND some of the stress on the transmission lines.

Re:Simple Tweakage

[csbruce]

We either need more power plants, to curb demand, or a fairly efficient way of storing excess power capacity in the winter to be used in the summer.

All you need is a means of storing off-peak supply for on-peak demand. I hear that in British Columbia, they pump water back up into hydro-electric reservoirs during the night. Maybe regular power plants can have big flywheels.

We can blame the environmental movement for there not being enough power plants.

Re:Simple Tweakage

[nhavar]

Bullshit, we can blame ourselves for overconsumption and the NIMBY's (Not In My BackYard) more than the environmentalists.

I hate that knee-jerk response to everything - "It's the environmentalists fault".

Even with all the technology that we've created to make lower power devices we just find a way to get more devices. I saw how they were working on LED's as a better, more efficient lightsource that can do task lighting for about 1 watt of power. I mention this at work and some jackass comes up behind me and says how cool it would be to be able to have a wall full of them and be able to change the color of his walls with his mood - POWER SAVINGS - what power savings?

It's a balancing act. First we have a grid that's just too old and extremely expensive to update. There's a mix of powerplants that are aging, there's poor planning, no incentive to change energy usage habbits, poor city design that promotes heat which in turn increases energy consumption due to airconditioners, extra showers, fans, and refridgerators. Then you have people who don't want a soot belching powerplant in their backyard, or off their favorite camping spot, nor do they want to pay extra for a more expensive cleaner burning plant, or pay extra tax dollars to have research into alternative plans like more efficient solar/wind/water/et al. Somewhere in there you have the environmentalists trying to conserve as much of nature as humanly possible before we end up having to chop down all the trees just to put up oxygen factories because we cut down too many of the fucking trees.

Noone wants to compromise their lifestyle to get to plan X, Y or Z.

My feeling is that we need a decentralized system where power is created in much smaller "nodes" and distributed from those points. Nodes could be created in house basements or in larger buildings and be connected to more evenly distribute power over shorter distances reducing the waste that happens when power has to be transmitted over miles and miles of cable to a destination. Additional efficiencies could be found as nodes throttle based on time of day and demand for their area. Grid failures would be reduced because nodes could throttle based on the failure of other nodes. We need more expensive but higher efficiency (and somewhat safer (no oil fires)) superconductor main lines. We need more incentive and more instructions on how we can save power and reduce use and what power saving products are good and can in turn save us money. We need much more diverse power sources Wind/Sun/Hydro/GeoThermal/FuelCell/Gas/Cleaner-Saf er Nuclear in much higher mix than we do today. We also need more cradle to cradle industries that take waste products and turn them into fuel for the next industry - reducing power consumption and limiting the need to dig more out of or cut more off of the earth.

I want giant catapillar like machines like TBM's that crawl through landfills chewing up trash and spitting out useful products. Sorting all the garbage into recycled materials and fermenting the rest as fuel to continue on in it's job or produce energy for nearby cities.

I want to see someone come up with a plan that doesn't attempt to single out ONE group of people as THE PROBLEM.

Management *is* key...

[neiffer]

The critical point here is that to have "exotic" devices, you have to be able to manage them to make the power grid meaningful stability. Often, the hip environmental crowd (okay, so I am often one of them), complains that there isn't enough use of alternative energy in the mainstream grid. However, if we dedicated a meaningful amount of the grid to energy extracted from yak dung, what happens if there are problems? The grid elsewhere has to make up the slack (often at a higher price and inefficient) or we have problems like last week. The more technology develops, the more we are likely to be able to use alternative energy...goo goo gah joob.

fuel cell

[fishbert42]

About two years ago I went to the Electrical Manufacturing and Coil Winding Association's Expo in Cincinnatti, OH. There, they had a number of seminars on fuel cell technology. There was much talk about the (at the time) brand new hybrid cars from Toyota and Honda, using fuel cell technology to power personal electronics, the challenges left to face in making fuel cell technology practical, etc. One possible future that was presented (15-20 years down the road, so they said) was having a large fuel cell power your entire home. I mean, it's your house, you could theoretically put it anywhere you want (even underground) so that it's out of the way, right? Residential electrical service might consist of a truck coming by to refill your home fuel cell every month or two. Anyway, if such a future were to come about, rolling blackouts like what we saw (or didn't see, come to think of it) in New England and eastern Canada could very well become a thing of the past.

Food for thought. But there's no guarantees that it's not half-baked. =)

Re:fuel cell

[tupps]

What about something like these: http://www.me.washington.edu/~malte/engr342/homewo rk/wq2001_homework/342.01.HW7s_tower.pdf Basic principal is you heat molten salt and then derive power by using the heated molten salt to generate steam (for a turbine). You therefore get cheap easy storage of the power and you can generate different levels of power from the system as is needed.

One of the issues that stops wind power.

[DAldredge]

Is that some rich 'environmentalists' don't want wind power where they can see it.

http://www.startribune.com/stories/484/4041637.h tm l

I guess that wind power is OK as long as it is in someone elses backyard...

The Y2K bug... A flashback

[RedCard]

Here's a question that I haven't seen asked yet... everyone's comparing this whole thing to the blackout of 1965, but what about the backups that were supposedly put in place to deal with the much-feared and hyped Y2K bug?

Wired 7.04 published an issues entitled 'Lights Out' that detailed many problems, including the problem of a single failure spreading across the entire continent.

Billions were spent in the USA and Canada on solving this... so where did that money go?

Re:Switch to DC

[bluGill]

DC still isn't perfect. When you get voltages high enough you can no longer make a circuit breaker for instance, because the sparc never stops. (There are solutions, most involving blowing something in the breaker so the plasma of the arc doesn't complete the circuit)

DC is also more dangerious. AC crosses 0 volts 120 (100 in europe) times a second, so if you touch a line and it doesn't fry you instantly you can let go, sort of. DC forces your muscles to contract, which can cause you to grab the conductor harder. (depending on how it effects you, it can also throw you violently away from the conducter). AC will relaxs those muscles several times a second giving you a chance to let go. And don't forget the arc in the previous paragraph if you do manage to let go of a DC line.

Of course in the voltages involved with cross country power transmission it is all theroitcial nonsense, you die either way. In lower voltages it can make a difference. Eventially voltages get low enough that it doesn't matter. Unfortunatly without knowing exactly where and how the power travels though you nobody can tell what will happen in any particular case, which is why we tell people to stay away.

As a last point though: induction moters cannot work without AC. This isn't going to be a point for much longer though. Already some manufactures are finding that it is better to use electronics to make their own AC to their specs. (Some maytag washers for instance use 3 phase moters, and the controller not only generates AC in the required 3 phases from the one phase that comes in, it sets the exact speed they want the moter to turn at eliminating complex gear boxes)

home use??

[canning]

Has anyone from Slashdot researched a home version of these wind turbines? Anything that would decrease monthly power bills involving a clean energy source is alright in my books.