Energy question for Anthracite

Naturally I’d like to hear anybody’s opinion, but since you’re the resident expert on energy generation, I thought I’d ask you, even though it’s not your specific area of expertise:

I read this article on the web, and I’m curious as to your take on it. How practical is this? How does it rate realistically against a coal or nuclear plant, in terms of efficiency, cleanliness, etc?

I know it’s probably nowhere near the capacity of a more conventional plant, but is it worth the expense of engineering and running it? Obviously, burning methane that would otherwise just be released into the atmosphere is better than not burning it, so there is a net benefit right off the top, but how much load does this really take off the grid? Is there enough of a payoff to justify building more in other cities?

I did get a good laugh out of this:

So now it’s producing about 892 megawatts, and by the end of the year, it should be up to 9.7 gigawatts! By 2010 or so, it would be able to cover the electrical needs of the entire known universe!

I hate sloppy reporting. You’d think that if you have a journalism degree, you’d know the difference between power and energy, or at least bother to find out…

I didn’t see the 892 MW nor 9.7 GW figures in the article.

But I did love the mangling of energy units. “Megawatts per hour” is like saying “miles per hour per hour”. I think they either wanted to use megawatt-hours, an energy unit, or just plain megawatt, a power unit.

Actually these are pretty common. See

for more examples.

In addition to using a resource that was previously wasted, and reducing global warming emissions, this type of technology eliminates a lot of the odor problems that landfills and sewage treatment plants have.

If you pay really close attention to your post, you answered your own question. how many hours has it been since Jan 28 (arbitrary late january day of my choosing)? 28 (feb) + 3 (end of jan) * 24 (hours in a day) = 744 hours. 744 * 1.2 (megawatts per hour) = 8.92 Mw = a goof on the ignorant reporting. Get it? If I produce 1 megawatt per hour, after 5 hours I’ll be producing 5 megawatts. I took the mistake and misapplied it literally.

maybe it was too early in the morning for me to be making bad jokes. haha :slight_smile:

A customer of mine
Is trying something similar with poor results. Apparently the landfill isn’t producing methane in high enough concentration to fire the boiler efficiently. They have to burn natural gas all winter to supplement the landfill gas.

Good intentions, but it’s just my tax dollars wasted, IMO.

*Originally posted by AWB *

Let’s get real here, folks. There is really nothing wrong with their units. Yes, MW (instantaneous measure)and MWh (integrated measure) are the technical terms and megawatts per hour is a bit more ambiguous. But honestly it is pretty clear what is meant and is probably easier to understand to the layman.

I have to disagree with you here. Fighting ignorance, and all…

A megawatt is 1,000,000 watts.
A watt is a unit of POWER: output of one joule per second.
A joule is a unit of ENERGY: the energy expended by exerting a force of one newton over a distance of one meter.
A newton is a unit of FORCE: the amount of force that will accelerate a mass of 1 kilogram by 1 m/s^2.

“Megawatts per hour” is not ambiguous, it’s incorrect. As stated, it means that every hour, the output of the plant
increases by 1.2Mw over the previous hour.

The units are very clearly defined, and the reporter (or the plant operators) used the term incorrectly. when you pay your electric bill, do you pay by the kilowatt, or the kilowatt-hour? If there’s no difference, then I think PSE&G should let me pay per kilowatt, that would save me a whole lot of money.

Geez, they weren’t writing an engineering textbook. Anybody reading that knows what they meant. I can see if you were taking your EE GMAT you would have an issue, but honestly…

Of course, I always try to show it as “MW*hr” in all the papers and presentations I do.

Off to read the article now…

1.2 megawatts per hour from the article is just plain wrong and they shoudl fix it. It does not give you confidence that the other stuff in the article is correct.

Actually, they are very practical in limited applications. They have a few issues though:

  1. Capacity - let’s face it - 1.2 MW is cool, but only supplies about 1200 homes. And that’s from an entire city’s landfill.

  2. Location - not many cities have landfills even that large.

  3. Err…well…believe it or not, some environmental groups actually oppose landfill gas generation, as do many homeowners nearby these landfills. Of course, they don’t realize that generating electricity and producing CO[sub]2[/sub] has much less of a greenhouse effect than just venting the methane…but they never learn.

Where it can be done, and where you can convince the unwashed masses that it is not the “tool of Lord Satan”, yes, it should be done. Granted it’s small capacity, but hell, it’s better than doing nothing. And methane in the atmosphere has much more of a greenhouse effect than the CO[sub]2[/sub] produced from burning it.

The reason this it is economical is that the “cost” of the fuel is hidden. The cost was paid for by the decades of garbage service payments of the residents of the city. Thus, it is not economical by some standards, but in real-world standards it can be very economical.

So it gets a “thumbs up” from Una. :wink:

PS - I too am disturbed by the use of MW per hour in the way they did, but then I don’t expect much from journalists who report on energy or envoronment issues. Even if I call or write them they never issue corrections. You should feel lucky they figured out that it produced “electricity”.

I still think it is nitpicking nonsense and is perfectly acceptable for the purpose of the article.

**Tretiak /b], you are entitled to think this is not important. But I cannot agree with you that it is “perfectly acceptable”. The effect is that the reader is immediately sceptical of the value of the article as a whole, since the writer demonstrates that he does not have a good understanding of his subject.

In addition, the mistake is not always unambiguous. The article says that the electricity is being sold at around 3 cents/kilowatt or $30/MW.

In this case, it probably means cents/kilowatt-hour. But it is possible (in this country at least) to buy capacity options, at say $30/MW. So it is not mere nitpicking to want to know which it is.

As it happens, my company runs a lot of landfill gas engines (about 15 MW) for electricity generation, and despite the high maitenance requirement, the free fuel makes it economically worthwhile. It is also very environmentally friendly.

Well it says energy and not capacity so I don’t see why one would get confused and think it is capacity. As for the importance of the “error”, I am going to remain in respectful disagreement against the SDMB world on this issue. :slight_smile: I certainly don’t think it in any way diminishes the purpose of the article, which is simply to inform the average newsreader of one of the more interesting electricity alternatives being exploited.

Hey, I wouldn’t have understood it if they had said ‘kilowatts’, with nothing else. The ‘per hour’ helped me get the point. Now I understand, but you don’t really need to leap down their throats.

This KW/KWh discussion is pretty much a nit-picky tangent to the main thrust of the OP, no?

Well, it did make up about half of the OP! :slight_smile:

I think it is a signfificant error.

In any case, you want nit-picky? What does the article mean by “generating electricity”?

What is electricity? (Most definitions are contradictory.) Do they mean electric charge, current, electrical power, or what? This site made me aware of the issue.

I started teaching this topic in class, and realized how confusing the term “electricity” actually is.