Manure-Powered Generators On The Rise

Sunkist writes "The San Francisco Chronicle has a report on Marin County rancher Albert Straus that, after 25 years of work, began using a generator powered by manure. While this type of 'power' has been in use for a while, recent legislation has made it more widespread. From the article, 'The Straus Farms' covered-lagoon methane generator, powered by methane billowing off a covered pool of decomposing bovine waste, is expected to save the operation between $5,000 and $6,000 per month in energy costs.' Let's hear it for poop!"

Comments

but on a serious note - Re:That's all well and

[Anonymous Coward]

I think a variety of energy-producing methods is a great first step towards lessening oil dependency. It doesn't have to be one size fits all: for some areas, solar would work well, others, wind or thermal. Less chance for monopoly that way as well. Then, we could use the oil that was still around for the situations that truly required it. Now if we could just get the prices down for the equipment it takes to use alternative sources....

You're missing the point --

[oneiros27]

They're getting energy from what was considered to be a waste product. If they weren't doing this, we would have to make larger nuclear power plants, or whatever other form of energy product you feel is acceptable for the environment.

This is a win-win situation, for those involved -- they de-water the waste, compact the waste for easier removal, and get energy back in the process to help offset the operational costs for the process.

For those who didn't take sewage treatment classes in college, there are four main types of setting -- type 1 is for things that accelerate from gravity (sticks, rocks, etc), type 2 is things that floculate (clump together as they're falling), type 3 and 4 are not typically done in a water treatment plant as they don't happen quickly enough. So, what they do is syphon off the 'mostly' clean water at the top, and dump the sludge at the bottom... but the sludge at the bottom is still mostly water, which is heavy, and bulky. Depending on the area, they'll spread it out to dry in the sun, or use anaerobic digestion (such as in the bottom of a pond), to get it to compress further.

And let's not forget that composted manure makes great fertilizer, which the farmer might otherwise be buying for the plants that go into feeding the cow. It's all just an example of a nice little ecosystem.

Great Tech - But I have a problem...

[HogGeek]

... with the following statement:

"With net metering, small producers like Straus can reduce or erase their energy bills but cannot be paid for pumping excess energy into the grid. Net metering has been available to owners of home solar systems for several years."

Why do we allow laws that strip us of potential income, and benefit companies like PG&E?

Fuel consumed in Feed Lots

[yintercept]

You are probably right. I personally doubt that the amount of energy produced by a methane powered generating plant in a feed lot would equal the cost of the energy consumed by farmers raising crops and shipping crops to the feed lot. This is more of a way to minimize the loss of energy from our fuel dependent farm economy.

Re:Doubtful

[strictnein]

A good example of made up PETA BS:

For example, a cow grazing on one acre of land produces enough meat to sustain a person two and a half months; soybeans grown on that same acre would nourish a person for seven years.

And the point is? Growing those soybeans for food using current methods requires anywhere between 12-18 times the energy that you receive from the food, including lots of nasty things like fossil fuels and fertilizer! OH NO THE PLANET IS GOING TO DIE! 7 years of energy for a human is ~ 7yr * 365days/yr * 2000kcal / day = ~ 5.1 million kCal. The EVIL TOXIC energy needed to create that food: ~61 million kCal - ~92 million kCal!

Having a cow graze that same acre of land requires no power as the energy in the grass it is eating is from the sun. No nasty chemicals, no icky big tractors. So, 2 1/2 months of food = 375000 kCal. To produce this food required only about 375000 kCal of FRESH HAPPY SUN energy. And they included only meat as a by-product of the cow. I can get milk too.

So, clearly in this setup (obviously things are different in real life, but I'm just going with what the super-smart folk at PETA tell me), the cow is the better alternative. I can eat its meat, drink its milk (if it's a female), wear its skin, and create power from its shit! All I need to make it through the year is about 4-5 cows and 4-5 acres of grass land. And since I'm using the shit to make power, I'm not relying on the nasty nuclear or dirty coal based energy! Three cheers for Mother Earth! Thanks for making it so clear PETA! If I love my planet, I should raise cows and eat meat!

Environmental impact

[operagost]

This naturally occurring methane is a potent greenhouse gas, estimated to be 21 times as damaging to the ozone layer as carbon dioxide.

Does this make any sense? I think the writer confused the greenhouse effect with the ozone layer. They're two totally different things! CO2 doesn't damage the ozone layer. It makes no sense.

All of this led me to one question

[TamMan2000]

The article talks about using a covered lagoon full of shit to collect the methane as the shit breaks down. The article said a well fed cow craps ~120 lbs/day.

How does the shit get to the lagoon?

At 120lbs/day/cow, moving that shit around could require a lot of energy. Are they only using the shit from the barn? Is there someone riding the range looking for shit? Are the cows wearing shit bags like horses in the city do? Are they doing anything to catch the cow farts (100-200 liters/day/cow according to the article)?

Well, I guess it was more than one question...

Can't see the grass for the trees

[Spamalamadingdong]

Think of the grass that has to grow and the nutrients placed into the soil, then what your body can't use is the crap. When it gets down to it... we would probably save money, and resources just growing tress on that land and burning those(skip the cow).

Your logic assumes that the trees are equally efficient in converting sunlight, water etc. to combustible biomass as grass is. Given that the candidates for biomass crops for feeding powerplants are typically not trees but grasses such as switchgrass, I strongly suspect that you are wrong there.

Replacing the cow might have its features, though. The cow is actually the indirect consumer of grass; the grass is first consumed by bacteria which convert its cellulose and other things to simpler carbohydrates and proteins (like growing mushrooms on straw) and then the cow digests the results. There isn't anything standing in the way of us growing such bacteria in vats rather than in cows and then feeding the results to e.g. fish, getting closer to the 2:1 feed/meat ratio than the cow's 8:1.

Re:The inherited problem is still

[richmaine]

Yeah. I once spent about 15 minutes researching an implausible-sounding statistic related to this that someone had quoted from Rush. When he isn't just plain lying, he uses statistics carefully crafted to give misimpressions. In particular...

He had a statistic about the amount of forested area in the US actually increasing by some significant percentage over a period of a few decades. In trying to figure out any way that this might actually be true, I realized that the decades in question covered the time when Alaska became a state. A brief check of an Almanac showed that Alaska accounted for the claimed growth and quite a lot more. Factoring that in, it was clear that the same statistic showed a pretty alarming rate of destruction.

Guess we just need to annex Brazil to keep the trend going. :-(

After that? Mars maybe? Can we somehow count Mars as all forested? :-)