Nuclear Versus Solar Energy
Rick Maltese is a bright, thoughtful guy, and makes some very solid statements on behalf of nuclear energy. He writes:
Statistically safety for nuclear power in the US does better than renewables, mind you it is only marginally. You may have noticed my blog before. The reason for the name “Deregulate the Atom” is to raise awareness about how a great technology has been prevented from maturing because of the over regulating authority of the Nuclear Regulatory Commission and the fossil industries campaign against their best competitor. I see the 3rd and 4th generation reactors as a huge improvement over the designs that were built 40 years ago and are still running. China will lead the way with the most number of new reactor designs.
My other pronuclear blog is http://thoriummsr.com which is supportive of molten salt reactor technology which is the safest design for a nuclear reactor possible.
Thanks for your posts against fossil fuels. They are well thought out and provide me with some ideas too. Best of luck.
Thanks, Rick. I’m not rabidly anti-nuke, though I do reiterate my concerns about waste disposal and cost.
Also, as I’ve written before, I’m not positive that deregulation is what you really want when it comes to something with the potential consequences of nuclear energy. Greedy coal companies cut corners, mines collapse, miners get sick, the coal companies cover it up, a few people go to jail, blah-blah-blah. That’s tragic, but I’m not sure I want to see this played out on a nuclear stage.
As far as I’m concerned, the most credible solution for a planet at this stage of technological evolution, 93 million miles from its star, a star that provides our Earth with 6000 times more power than we need, is to find a way to tap into that energy stream. Here’s the poignant part: if it weren’t for the power of the almighty dollar, the fossil fuel monopolists wouldn’t have the stranglehold they maintain over our political discourse, and we would already have clean energy in the bag.
“Thanks, Rick. I’m not rabidly anti-nuke, though I do reiterate my concerns about waste disposal and cost.”
Certainly valid concerns. However, it looks as though molten salt reactors, of which the lithium fluoride thorium reactor (LFTR) is a subset is a good solution. Because the fuel is a liquid during operation, on-site fuel reprocessing is easy. It’s simply a matter of bleeding off a small portion of the circulating fuel, reprocessing it, running the good fuel back into the reactor, and dealing with the small amount of waste.
From my extensive reading, it looks as though the actual waste from that type of reactor is only about 1% as much as with our popular solid fueled uranium reactors. And, the waste that does exist, decays quickly enough that after only a few hundred years, is no longer hazardous.
Little is 100% certain, but the molten salt reactor, and its LFTR subset, look so promising that we’d be foolish indeed not to work at developing them as quickly as possible. A LFTR prototype was operated successfully for about 25 years which further indicates its potential.
From what I can see, the world is hard at work at developing this and other forms of nuclear technology, though its (thorium’s) successful completion still lies far in our future, if it lies anywhere at all. Is your point that we should be working on this harder/faster? I’m sure you’re aware that we’re spending many tens of billions of dollars on advanced nuclear.
So far as I can see, here in the U.S. very little actual development work is being done on developing molten salt reactors although a number of private groups have meetings and are doing some promotional work. On the other hand, China seems to be very serious about developing it.
The reality of global warming is such that something on the scale of the Manhattan project could be rationally justified, although probably something on that scale would be politically unrealistic.
Here’s a document that I discovered just a few minutes ago:
http://thoriummsr.com/
Renewables, especially solar, do have an important rôle to play in remote areas of developing countries. In those places, even small amounts of electrical power can greatly improve quality of life. The LED lighting it enables is more economical and safer than kerosene and the additional light makes it easier for kids to do their school work. Even in those remote areas, many parents very much want their kids to do well in school both so that the kids can have a better quality of life and so that the kids can support their parents in their parents’ old age. Even a few watts of power for a few hours every evening can make a big difference and solar can provide that very well. Even in remote areas, people have cell phones and recharging them is a serious problem that PV power can easily solve. It can also operate notebook computers and small TV sets. What renewables cannot do, in my opinion, is provide sufficient, reliable, and economical power for large prosperous countries, but that does not make it useless.
Hey guys, Rick Maltese gave word of a productive conversation about renewables, like solar and nuclear. I want to start by staying solar and nuclear aren’t enemies, they aren’t really fighting for the same spotlight positions. Solar is really best as a peaking power source, good for midday when life on the planet from humans is at its peak, and nuclear is really good at providing safe, reliable, clean base load. If you like clean energy because of climate issues, then you like both nuclear, and solar (and a host of others).
I remember hearing about water based cars once. That a swimming pool of water contains the amount of energy the world uses in a day. Problem is, you can’ readily separate hydrogen (fuel) from oxygen without a huge energy penalty (you spend more then you get back). So while things look good on paper, it is physics and practice applications of technology that bring us back down to reality. So while numbers look good on using solar power because of facts like “every second more energy hits the surface of the earth than man has ever produced”, the problem isn’t how much, but how you get it.
The main problem I ended up always coming back to was energy per square meter. For any given system, you are going to have losses, usually pretty major when it comes to energy conversion. The best solar cell we could ever make, in theory, could be 45% efficient. That is pretty good as far as other power conversion goes (nuclear is only 40%ish, interal combusion worse still)…but solar is unlikely to ever reach this. In our lifetime, we might see a 30% cell (already getting pretty close to that, but they are super costly, mostly lab room only). But current cell tech is usually more around 10%-20% for really costly stuff (but doable on a small house). They don’t use that stuff in solar parks, they usually use the really cheap stuff, like 5% efficiency. So right away, we have eaten into that huge number from the great fusion generator in the sky.
I live down in Texas, so we get some serious sunlight, more than a great deal of the north of the country. Up in Dallas, a while north from where I live, there is some good solar data. On average, considering cloud cover, night, seasonal dips in solar output; the yearly output of a square meter of ground comes out to about 200 Watts a square meter. Pretty decent amount really.
But then those conversion factors start to smash us in the face a bit. Let’s be really generous and see how many square meters it would take to power our existence (total energy usage) factoring in the best cells money can buy, some nice 20% conversion cells! We will even say they are super high tech and follow the sun perfectly so they always get that maximum value. We will also assume they never get dirty to lower the conversion efficiency; pure back of the envelope goodness (my favorite!).
********Warning math to follow!**************
So for our square meter of dirt, we will generate about 40 W/m². Hey, that is about an incandescent light bulb of energy, not to shabby. But we want more, how much more exactly though? Well, in the USofA, per capita energy consumption a year is 91,002 kWh/y. To put us in similar units for what we want, we devide by the amount of hours in a year (8766), and we get 10.4 kW of capacity needed to supply our needs. Our 40 Watts is .04 kW. A simple division and we get our answer. 10.4kW/.04kW/m² = 260m². Walla! 260m²ish meters to power your existence.
What does all that mean exactly? Well, this means that if wanted to adopted an all solar solution, we would need to expand the biological footprint of every man, woman and child in the country to 260m². Hey, it’s a big country…can we do it? Let’s find out (ish)! So if I look out my window and do a head count, there are about 311,591,917 people in america currently (I might of actually Googled that information). So 260m²*311,591,917’mericans = 81,013,898,420m²’mericans (not yet a standard SI unit). Meters are a kind of small unit when dealing with landmasses so lets convert to km, 81014km. That seems more reasonable…but how big is that? Well, that is about as big as South Carolina, at 82,932m². O…well, that is kind of big. C+C Music Factory might refer to this number as “Things That Make You Go Hmmmm”.
***********Dear gosh the math is done, thank goodness******
The energy problem is pretty complex when you start to do the actual math and heavy lifting on what is actually attainable. Nuclear has the same kind of issues, sure it is powered by e=mc², sure a lifetime supply of energy is about the size of an orange, but you have to deal with the waste, you have to have lots of people making sure weapons materials aren’t being made, ect. I just want to be clear, there isn’t a picture that is all rainbows, all choices have a set of technical problems with them, some very hard to deal with. I for one, place a lot of faith in nuclear being a great base load source of carbon free energy, with things like wind, solar, hydro, geothermal, providing intermittent peak load based on regional abilities. It would be a good system that is a much more sustainable for future man.
A man much smarter than me has a great book I am reading called “Sustainable Energy – without the hot air” ( available for free by himself at http://www.withouthotair.com/). Which is a really fun book talking about all the different forms of green energy, and how they look on back of the envelope calculations like this. The energy crisis is where I have decided to make my life focus, so any continuing conversation is always a a desirable thing to me, so I can be found at my facebook @http://www.facebook.com/willis.christopher.a and would love to continue any further discussion either here or there. I still think solar has a place in the energy future, I just want all solutions to be in the best place…a place that makes sense with the physics and technology we can bring to bear! The current global energy market for dino fuels (gas, coal, and people who move it drill it…everyone) is 10 trillion…a year. Once you understand this amount, it is easier to understand how hard it is to roll out any system to replace it…that is a lot of vested interest and a lot of market share to overcome.
I shall end this madman’s rant and hopefully we will have a brighter future with conversations like this.
Doh, a few typos, one major, the South Carolina measurement is correct, but has incorrect unit. You can fact check this here
(82,276.84km²)
http://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_area
And I missed the square on the total surface area of our megasolarpanelofdoom.
My apologies, I should edited twice and not at 1 in the morning.
NP. This is very good. Please see: http://2greenenergy.com/solar-pv-takes-room/32788/.
” So while numbers look good on using solar power because of facts like “every second more energy hits the surface of the earth than man has ever produced”, the problem isn’t how much, but how you get it.”
I like that. Too often we read figures about how much solar energy the earth receives per year. That information is about as useful as knowing how far Saturn’s moon Titan is from Saturn.
We often read how many tons of nuclear waste there are. I wish the figure were also stated in cubic feet or cubic meters, or how deep the waste would be on a football field. The waste is very dense and the actual volume is much less than one might imagine.
Also, there are ways to eliminate most of the waste, either by reprocessing it and using it as fuel, or by using a nuclear technology that produces less than 1% as much waste as our most popular current nuclear technology. With molten salt reactors, of which the liquid fluoride thorium reactor is one type, the waste can easily be processed on site and it would be impossible for anything to be stolen which could be used for weapons.
Probably practically all the problems associated with nuclear energy are the result of implementing the wrong nuclear technology.
“Too often we read figures about how much solar energy the earth receives per year. That information is about as useful as knowing how far Saturn’s moon Titan is from Saturn.”
I firmly disagree, Frank. The amount of energy we receive from the sun daily is highly relevant to our own planet and our biosphere, and these numbers shared on this site – 6000 times the total electricity use – obviously serve to encourage the wider acceptance of the known and demonstrated viability of solar thermal, and solar energy applications in general, among readers who have not been exposed to the numbers elsewhere.
In contrast, the distance between Titan and Saturn is useless to nearly all but astronomers and spaceflight technicians. I strongly suspect that you must have realized that your comparison is complete hyperbole, and therefore not particularly useful in itself.
Your comment reveals a level of antagonism toward solar thermal that is quite unwarranted, given the potential of efficient High Voltage Direct Current transmission over long distances from both ideal and highly suitable climate areas that are widely dispersed in many nations (and therefore available to nearly all nations), and given the recent advances that resolve concerns about storage. Indeed, people in Germany are looking at solar generation in Africa for consumers in Europe.
Solar thermal a relatively simple and highly elegant solution set that is being seriously pursued by entities both commercial and governmental, and they are thoroughly considering and addressing your aging concerns. Advances continue and efficiencies increase – it is only a matter of time and political will.
Solar thermal for heat can make good sense, both for heating homes and supplying domestic hot water. It’s efficiency can slightly exceed 50%. It’s unclear why there is so little emphasis on that here in the U.S. In some countries, solar hot water heaters are very common, but not here. For generating electricity, it’s a different matter; because of its intermittent nature and the limited salt tank storage available, it depends on other sources of power for backup.
@Christopher WIllis: Thanks for the great mathmatical representation of my square foot solar needs. Now I know(ish).
If the average American per capita energy consumption each year is 91,002 kWh/y, it seems to me that we need to reduce our energy consumption in the USA. Energy efficiency is very cost effective compared to electrical generation. Heating and cooling buildings is responsible for 40-some percent of American energy demand. Why heat a building in winter, just to cool it in summer? Can’t we store some of the summer heat underground? Geothermal heat transfer seems simple enough to me. Send BTUs underground during summer, which cools the building. During the winter, draw that heat back out to warm the building. A geothermal heat pump uses a small amount of electricity, compared to even a high efficiency gas furnace, and much less electricity than an average, American air conditioning unit.
If every home had a solar thermal water heater, with a solar PV system on the sunny side of the roof, and a geothermal storage and recovery system, the annual energy need would be less. Maybe the home would need a battery type electricity storage unit to operate over the 24 hour day.
If the family had an electric car (or plug-in hybrid electric) powered by the same PV system, it would reduce the use, transportation and pollution otherwise caused by petroleum fuels.
Solar can reduce demand for polluting sources and be cost effective.
In some circumstances, geothermal heat pumps can be very cost effective for both heating and cooling. However, when my new house was in the design stage, I found that the investment cost of geothermal heat pumps was excessive. There are ways around that problem.
The consumer cost of electricity does not include externalities which should be included. Doing so would increase the consumer price of electricity thereby making geothermal heat pumps more attractive for cooling, but not for heating.
Increasing building energy efficiency is costly which wouldn’t necessarily be a problem if the cost could be recovered on resale and if it did not increase property taxes. When a house is put on the market, either when it is new or when it is being resold, the advertising for it should in some way indicate energy efficiency and enable prospective buyers to see the point of buying a more energy efficient house even if it is more expensive.
Curious… Does this 91,002 kWh/y figure include all forms energy consumed by the average American, or just electrical energy?