On Electricity (Generation)

Engineer-Poet wrote a piece a few months back that focuses on electricity production; or rather how or what we will need to do to keep pace with people's demands while balancing that with environmental and economic impact. Lengthy but well-reasoned and good reading.

This is mentioned in the article

[paladinwannabe2]

Not that anyone reads those pesky things... but your concerns are mentioned.

It's not that it's energy negative- we still come out ahead- it's that it's not energy positive enough. There's a lot of other things we could be doing with that corn instead of turning it into ethanol. We are paying tax money through subsidies for something that's not going to be a long term solution. It's a waste of money and resources that could be spent elsewhere.

A couple more technologies

[mdsolar]

This is a really nice piece of work. A couple of technologies that were missed are marketing mechanisms related to solar http://mdsolar.blogspot.com/2007/01/solar-power-am way-way.html [blogspot.com] and fly wheels http://mdsolar.blogspot.com/2007/01/saving-not-bor rowing.html [blogspot.com], described on the Real Energy blog.

Oil? What about soil?

[RyanFenton]

Sure - the proposal to produce charcoal will allow for some soil renewal, but to allow this process to become sustainable, we'd also have to manage our soil resources much more carefully than we have been. Oh well, one problem at a time, I guess - global warming-related climate change would likely destroy even more viable soil than this proposal (it dries quicker in some spots, erodes others much quicker), so it's certainly an improvement.

Ryan Fenton

Re:They're typical media

[div_2n]

I've been around quite a few what I would consider hard core environmentalists and I've never gotten that impression. In fact, some of them seemed to be apprehensive about ethanol because of how they view the impact some of the corn production in the US has on the Mississippi delta--i.e. the dead zone.

Maybe I've been around some of the more logical and open minded environmentalists, but my recollection is that they seemed to think solar and wind hold the biggest promises with ethanol being good if the major issues can be worked out.

Re:Wrong

[AKAImBatman]

Ethanol is being used to reduce emissions on that small fraction of badly running automobiles out there. It does not have any effect on modern engines except to lower their mileage. Modern engines don't even require the "higher" octane rating, as they can compensate as required for slightly lower octane ratings.

This is an incredibly naive take on Ethanol consumption. The higher octane does have an effect. That effect is to burn the gasoline hotter and more completely, thus extracting energy than would have otherwise been extracted from a lower octane fuel.

It's true that in a pure-ethanol vehicle, you'll need more fuel to make up for lower energy density. However, the faster and hotter burn cycle can be compensated for, allowing engine designers to extract a fairly competitive amount of energy from the fuel.

The lower energy density just isn't that big of a deal when the choice is between needing 20% more Ethanol fuel at $2.50/gal vs. purchasing petroleum fuel at $3.75/gal.

Nuclear is still using "stored" power, thus can still have a net add to planetary heat.

This must be the oddest argument I've ever heard against nuclear power. First and foremost, any escaped heat is wasted energy that could have been used for electricity. So plants try to loose as little as possible. However, they do lose some, but nowhere near enough to have an impact on global conditions. "Global Warming" models are not based around how much heat that power plants release, but around concentrations of greenhouse gases that hold heat in. The theory is that if the concentrations were lowered, the Earth would be better able to radiate away the excess heat.

Re:Wrong

[Anonymous Coward]

The heat added by nuclear power plants will be as significant to heating this planet as rubbing your hands together is significant in heating your house.

This is not correct, the effect of the nuclear power plant is not the heat that it generates when generating electricity, it is all the electricity that is eventually transformed into heat when it is used. It wasn't heating anything at all as uranium ore, it was stable and a stored energy source.

So what. A 3 GW thermal plant (meaning typically 2 GW are waste heat and 1 GW is electricity) still cannot compare with the solar flux of about 1 KW per square meter. A little over one square mile of land in the daytime will have the same amount of energy deposited by solar flux as the nuclear plant will generate. Feel free to calculate how many square miles of the Earth are facing the Sun at an given point in time and tell me how a thousand or so nuclear plants would make any difference.

Plant waste heat is trivial

[Engineer-Poet]

World annual human energy consumption (about 400 quads from all sources, including nuclear heat input to electric production) is equivalent to about 40 minutes of global solar input. The direct effect is utterly trivial save on a very local basis; the warming we're seeing is from greenhouse gases which trap more of the 5.2 million quads of sun striking the atmosphere every year.

Actually, that's Wrong Too

[jfuredy]

This is an incredibly naive take on Ethanol consumption. The higher octane does have an effect. That effect is to burn the gasoline hotter and more completely, thus extracting energy than would have otherwise been extracted from a lower octane fuel.

Higher octane fuels actually decrease the temperature and speed of the fuel burn, thereby reducing knock, or preignition. There is virtually no difference in the total energy between a high octane and a low octane fuel. The difference is just in how readily the fuels are ignited.

I have a 2-Tank Car already.

[jlcooke]

But it's not a Ethenol hybrid.

It's a 2001 VW Jetta TDI. Diesel. Installed a GreaseCar [greasecar.com] system. Works well, but not in this weather (-20C..-30C).

Pretty much every other time of the year, I start on DinoDiesel and once things get hot enough I switch to Waste Veggie Oil I get and filter to 10 microns [filterbag.com] from a local pub.

The article puts things together in a clear way. Points out what's wrong with the nut-jobs who think the world can be run off of butterflies and rainbows.

To those back-and-forthing on Ethenol - think about how much energy there is in a litre of ethenol. It's very very small. Production is expensive ($$$ & energy).

I don't 100% agree with the article's view on charcol fuel sources. But I like the analysis, not many gems like that.

My thoughts on how to solve this? Okokokok I'll tell you anyways. Grow alge, crush it into oil and use that. Alge grows 100x faster than canola/soy/rapeseed, is 50% oil, and only requires sunlight, (non-)salted water, heat, dirt and shit. No expentive farming equipment guzzling diesel to harvest. Just settling ponds like at the local water treatment plant to skim off the alge.

Anyways. Alge == good. Alge has had about 3-4 Billion years head start on Solar-power. Don't believe me? Take a deep breath.

Re:Plant waste heat is trivial

[Eunuchswear]

Quad quad quad - what is this quad of which you speak?

Oh 1E15 BTU, about 1E18 Joules, or 230 megatons if you prefer it in one go.

Re:Actually, that's Wrong Too

[Anonymous Coward]

Higher octane reduces pre-ignition. Period. It does not lower the temperature of the burn or any other nonsense like that. Ethanol burns hotter and faster than gasoline. Its use as an additive doesn't change that.

Technically, the most efficient octane rating is the one that the engine is tuned for. Modern engines are computer controlled to tune for E10 fuels when they are used. Which means that a modern automotive can run more efficiently on a higher octane ethanol blend.

Re:100 Years of Fission / Reliable Lift

[Control Group]

Tangentially (literally):

Orbital mechanics dictate that it's far easier to fling mass out of the system than in towards the sun (this having primarily to do with an existing angular velocity around the sun of ~30,000 m/s, borrowed from Earth's solar orbit).

Practically speaking, of course, there's no difference between throwing the waste out of the system and into the sun. The percentage of people who would honestly raise a "polluting the universe" concern has got to be vanishingly small. If it isn't, we're finished a species, anyway.

Re:What does nuclear energy cost?

[QuantumPion]

Hum, you've forgotten the incredible subsidy nuclear power gets: It's been promised not to have to deal with the waste. That promise is not at all realistic since Yucca Mountian can't go forward. So, we're in a postion where we'll have to pay back all the energy we've ever gotten from nuclear power and then some. How much more expensive can you get? See: http://mdsolar.blogspot.com/2007/01/saving-not-bor [blogspot.com] rowing.html

That article is a load of crap. Basically, what he is saying is that in order to clean up all of the waste we've generated, we need to use high energy particle accelerators to split apart every last atom of radioactive waste, and since the particle accelerator would require more energy to run then what we obtained from the nuclear power to begin with, it's therefore not worth the trouble. This is equivalent to saying that fossil fuels can't be economically used, because the energy required to rebind the molecules after they are combusted is greater then the energy used to burn them to begin with. It's a ridiculous argument and is wrong on so many levels I'm not going to go into it here unless you really want me to.

And your original point is wrong. You are backwards, power reactors don't receive subsidies to dispose of their waste. They've been paying into a DOE waste fund since 1982. The cost of waste disposal has already been factored into the economics of their operation.

Re:What does nuclear energy cost?

[QuantumPion]

It's true that Yucca mountain will most likely not be used as a commercial power reactor waste repository site. But it is not as if the billions of dollars in the nuclear waste fund will go to waste. The money will be used towards another storage solution or, more likely, waste reprocessing.

As for the insurance costs, it most certainly is not free. Power plants spend huge amounts of money for their liability insurance. What you are probably thinking of is the price-anderson act, which states that power companies are only liable for the first $10 billion in damages due to a nuclear accident, where the federal government picks up the rest. While the act makes it so that people cannot sue the power companies for _punitive_ damages in a nuclear accident, it also states that the power companies cannot defend any action for damages. It's a fair two-way street that makes nuclear power commercially possible.

According to the wikipedia article on the price-anderson act, the actual subsidy comes out to around $2 million per reactor per year. That seems fairly modest to me, considering the financial risk power companies invest in the plants and their benefit to the country via clean, reliable power.

Ive said it once, and Ill say it forever more...

[Smoke2Joints]

Energy generation needs to be localised. Everyone needs to be aware of their usage, control it, and take on the responsibility of generating it themselves, be it photovoltaic, wind turbine, or micro hydro.

Re:Actually, that's Wrong Too

[homer_ca]

You're right about higher octane fuel being more resistant to knock and pre-ignition. As far as tuning for fuel octane, the only things that the engine computer can adjust are spark timing, fuel mixture and the maximum boost in a supercharged engine. The most important parameter, compression ratio, is fixed in the physical structure of the engine.

A high compression engine can take advantage of higher octane fuel, but it doesn't care if the octane boost comes from ethanol or some or ingredient. The important parameter when tuning for ethanol blends is fuel mixture because alcohol already contains oxygen (in effect, it's a little "pre-burned").

Re:Mostly right

[Anonymous Coward]

Uranium and Thorium will happily decay wherever they happen to be, and there are significant natural nuclear reactors involving naturally occurring radioactive mineral deposits.

In a sense all nuclear power generation does is compress this natural decay spatially (through refinement) and temporally (early fission chain reaction).

This is not very different from fossil fuels, only the waste from nuclear power generation is in the form of actinides and other wastes from fission decay and neutron bombardment, and stays contained in one place. The waste from fossil fuels is greenhouse gases and ash, and one of the greenhouse gases (CO2) is largely released to the atmosphere.

Neither fuel violates the principles of thermodynamics, and power generation from both types of fuel does not noticeably influence the temperature of the planet, or even of a volume with a radius of more than a kilometer.

Both fuels have dangerous waste products, and one of those waste products prevents long-wavelength radiation from being radiated to space.

Re:Related Reading

[scottv67]

paint roofs dark colors in colder areas.

I'm not sure if you're hoping for the sunlight that hits the roof to heat the living space inside the house or what. The area between the top of the living space and the roof (commonly called 'the attic') is not supposed to hold heat. Fresh air comes in through soffit vents and hot air is exhausted through vents at the roof's ridgeline. In the winter, I don't want my attic to be warm. I want it to be as cold as the air outside the roof. Warm air in the attic encourages the snow on the roof to melt which leads to ice. And that'll ruin your roof.

So, the color of my shingles doesn't really matter much in the colder times of the year. I'm not counting on the attic to heat the living space in the house. In the summer, I'd like to have a lighter colored roof because the high temps that can develop in the attic (even with the proper air inlet and exhausts in the roof) definitely make the living space warmer.