Should nuclear energy be phased out?

[russ_watters]

No, phase out the use of air-conditioning. You say it is significant, but I am curious as to how significant it is. Can you provide a statistic for that?

HVAC is roughly half of a building's energy usage (commercial or industrial). Energy is roughly $1.5 trillion or 15% of the US GDP (based on 100 quadrillion btu of annual usage at 5 cents per kwh). Someone check my math.

http://energy.cr.usgs.gov/energy/stats_ctry/Stat1.html
http://zone.ni.com/devzone/conceptd.nsf/webmain/6E14CD46F2DBE74586256E2100798272?opendocument&node=200768_US

It is also important to remember that cutting energy is a double-hit to the economy and cutting hvac makes it a triple-hit: Cutting energy usage hurts the energy industry and whatever industry you are cutting it from: cutting it from HVAC hurts the HVAC industry, and cutting HVAC hurts every industry that uses HVAC. Ie, buying a house without HVAC will cost less than buying a house with it, hurting the construction industry, construction hardware industry, finance industry, etc.

They would have to be replaced, but again that's the price you have to pay.

Just saying that doesn't tell us anything at all about how you'd go about doing it or what effect it would have.

Might not meet the goal, but it will take a step in the direction of the overall goal none the less.

In my opinion, such baby-steps are counterproductive because they waste time. While we take baby-steps, the situtaion just keeps getting worse.

Then you cool the individual computers themselves, not the entire office building.

It works out largely the same either way. In offices, the computers are responsible for most of the HVAC anyway. Whether you pipe the air conditioning to the computer itself or just to the room, the heat from the computer is still going back to the hvac unit.

Don't get me wrong. If we can maintain our way of life, and find better ways to get power while reducing the effects on the environment, GREAT! But I find this very hard to believe, because when most of the world gets out of 3rd world status, we will have a major energy crisis on our hands. Eventually, cuts will be inevitable. (Unless we get some technologies that can supply the increased demands within that time frame, which is debatable)

We already have a technology that works just fine. It's the subject of this thread.

 

[russ_watters]

The reason it is called 'clean coal' is because it is not burned!

People may be calling it different things, then: http://www.fossil.energy.gov/programs/powersystems/cleancoal/

"Clean coal technology" describes a new generation of energy processes that sharply reduce air emissions and other pollutants compared to older coal-burning systems...

Initially, the demonstration portion of the program, the Clean Coal Power Initiative, is providing government co-financing for new coal technologies that can help utilities meet the President's Clear Skies Initiative to cut sulfur, nitrogen and mercury pollutants from power plants by nearly 70 percent by the year 2018. Also, some of the early projects are showing ways to reduce greenhouse gases from coal plants by boosting the efficiency at which they convert coal to electricity or other energy forms.

It is gassified by heating to 2000 F which breaks it down into it's constituent chemical building blocks. These are then distillated and so what were harmful emmissions become useful by-products such as anhydrous ammonia and ammonium sulfate for use as agricultural fertilisers, phenol for use in manufacturing wood resins and naphtha and liquid nitrogen which have many uses.
The CO2 produced is captured and as I outlined in an earlier post can be used to help extend the useful life of oil wells or simply sequestered underground.
The net result is there are zero emmissions from a plentiful raw material source with none of the longterm environmental / health risks associated with nuclear power.

That technology is not off the drawing-board yet, and I think in the near-term we need to use technology that has already proven itself to be commercially viable. We could be building nuclear power plants now and in just a few years make a significant dent in our fossil-fuel dependence. Not these single-digit differences - in a couple of decades we could all but eliminate fossil fuel energy production.

With regard to the US reducing it's usage of power one of the most obvious ways to do this without changing a single thing in how power is currently used is by converting the supply system to use HTS cables.

The amount of power currently lost through electrical resistance in the transmission grid is immense.

Compared to the magnitude of the problems we're talking about, I don't consider 7.5% to be "immense" - I don't even consider it worth talking about. Coal power alone is currently half of our electricity generation.

Transmission and distribution losses in the USA were estimated at 7.2% in 1995 [1], and in the UK at 7.4% in 1998. [2]

http://www.answers.com/topic/electric-power-transmission

Another interesting area under development is HTS motors, prototype 36.5 MW (47,000 HP) ship propulsion motors have been produced for the US navy weighing 1/3 and taking up 1/2 the space of conventional motors of the same rating. Many ships have already transitioned to electrical propulsion systems making the next step to HTS systems far simpler. It is estimated that if a cruise ship used a HTS propulsion system it would save ~$100,000 a year on fuel.

Again, the numbers we're talking about are miniscule (I'm skeptical of that $100,000 a year savings, but anyway...). Such motors have been demonstrated at 97.2% efficient whereas conventional electric motors are up to 96.8% efficiency - a difference of less than 1%.

http://www.psnh.com/Business/SmallBusiness/Motor.asp
http://www.amsuper.com/products/motorsGenerators/104213395711.cfm

Oh, and where does the electricity come from to power such motors? From an oil-fired gas-turbine engine that could have been connected directly to the screws anyway.

 

[Cyrus]

We already have a technology that works just fine. It's the subject of this thread.

Well, let's assume the world is peaceful. There is no disputes, we are all one big global community. We all use nuclear power, and we have eliminted all needs on fossil fuels. What would be the amount of nuclear waste produced by these production plants? Also, where would you propose we put all that nuclear material?

 

[russ_watters]

Cyrus I think that there's a bit of a conflict with trying to decrease energy usage. Yearly we want to make sure that more and more people have clean water, food, clothes, shelter, heat/air, medical care, education, transportation, jobs, ect ect... in essence if we try to meet these goals more people are going to be using more energy yearly. I'm sure that these are goals you would whole heartedly endorse and would like to see met on a larger percentage yearly.

Yes, I've glossed-over thos issues a little bit. The productivity losses we'd see due to people being uncomfortable at work would be huge. Our kids would not be as well educated because they can't pay attention in school if they are sweating. Disease would increase due to poor indoor environmental conditions. When I say that HVAC is one of the things that makes the modern world the modern world, it isn't just about comfort alone - comfort is required for making the world run as efficiently and productively as it can.

 

[russ_watters]

Well, let's assume the world is peaceful. There is no disputes, we are all one big global community. We all use nuclear power, and we have eliminted all needs on fossil fuels. What would be the amount of nuclear waste produced by these production plants? Also, where would you propose we put all that nuclear material?

All that nuclear waste could still fit inside a single football stadium and we could put it just about anywhere. But why even bother? As I said before, we could even leave it where it is now, not hurting anyone or anything.

 

[russ_watters]

Consider the waste data a little further: http://www.uic.com.au/wast.htm

A 1000 MWe light water reactor uses about 25 tonnes of enriched uranium a year, requiring the mining of some 50,000 tonnes of uranium ore. By comparison, a 1000 MWe coal-fired power station requires the mining, transportation, storage and burning of about 3.2 million tonnes of black coal per year. This creates around 7 million tonnes of carbon dioxide not to mention sulfur dioxide, depending on the particular coal. Solid wastes from a coal-fired power station can be substantial and cause environmental and health damage.

 

[Art]

People may be calling it different things, then: http://www.fossil.energy.gov/programs/powersystems/cleancoal/ That technology is not off the drawing-board yet, and I think in the near-term we need to use technology that has already proven itself to be commercially viable.

Your information is a couple of decades out of date - see Dakota Gasification Company's Great Plains Synfuels Plant. http://www.dakotagas.com/ BTW The process was first developed and used by the Germans during WW2 to provide fuel for the luftwaffe.

We could be building nuclear power plants now and in just a few years make a significant dent in our fossil-fuel dependence.

We could be building Clean Coal Plants now and reduce harmful emmissions to zero without the headache of disposing of nuclear waste or incurring the high costs >$300 m each in decommissioning the plants at the the end of their useful life. http://www.nrc.gov.edgesuite.net/failover.html Apart from disposing of the spent fuel remember when the plant is decommissioned much of the construction material is also irradiated and needs to be disposed of safely.

In the US, 10 defunct nuclear plants have been decontaminated (the Decon method) whilst 14 have taken the safe store (Safstor) approach whereby they are mothballed to avoid incurring the costs associated with their demolition. I believe the plan is to leave them that way for 50 - 60 years. The 3rd option for handling defunt nuclear power plants is entombment which as the name suggests consists of enclosing the structure in some material such as concrete. This is used by some countries. Neither Safstor nor entombment are very nice legacies to hand down to your grandchildren.

Some people here have spoken about reprocessing fuel to extend the life of the nuclear era but the decommissioning costs involved in cleaning up reprocessing sites is huge. The French Atomic Energy Commission is decommissioning the UP1 reprocessing plant at Marcoule. Progressive decontamination and dismantling of the plant and waste treatment will span 40 years and cost some $6.5 billion , nearly half of this for treatment of the wastes stored on the site.

in a couple of decades we could all but eliminate fossil fuel energy production.

If fossil fuel is the most environmentally friendly, cost effective way to go why would we want to eliminate it? Especially as somebody here already pointed out there is only enough nuclear fuel for 30 years anyway and as I already pointed out enough coal to last 300 years, with the added advantage the resource is yours and so doesn't incur the problems involved in achieving a stable energy supply from politically unstable regions of the planet

Compared to the magnitude of the problems we're talking about, I don't consider 7.5% to be "immense" - I don't even consider it worth talking about.

7 1/2% equates to something like 12 power stations. That sounds worth talking about to me. But then again you seem so keen to push the notion that anybody advocating saving power is a 'dark age environmentalist' I can see why you are so dismissive of substantial savings with no loss in standard of living.

Coal power alone is currently half of our electricity generation.

Precisely so the infrastructure is already in place to support clean coal power plants.

http://www.answers.com/topic/electric-power-transmission Again, the numbers we're talking about are miniscule (I'm skeptical of that $100,000 a year savings, but anyway...). Such motors have been demonstrated at 97.2% efficient whereas conventional electric motors are up to 96.8% efficiency - a difference of less than 1%.

HTS motors are far more efficient than conventional motors at low speed. The $100,000 figure I quoted was the lowest end of the scale.

HTS Propulsion Systems Operate Equally Efficiently at any Speed As noted earlier, HTS propulsion systems have the additional advantage of being able to operate just as efficiently down to low speeds, which is especially important for cruise ships, coastal merchant ships and warships that spend much of their time operating at partial loads. Overall, the fuel savings from efficiency gains of HTS machines depend on the operating scenario but preliminary calculations suggest that fuel savings from $100,000 to $500,000 per ship per year can be expected for many ship types.

http://www.amsuper.com/products/library/Maritime_Reporter_final3_sk1_73002_final.pdf (you'll note this is from the source you quoted)

Oh, and where does the electricity come from to power such motors? From an oil-fired gas-turbine engine that could have been connected directly to the screws anyway.

It seems only diesal direct drive ships are built, for which I am sure there must be good technical reasons but you'll be pleased to know they are also working on HTS generators too.